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Posted at 1:00 PM ET, 01/25/2011

Odds increasing for heavy, wet snow late Wed.

By Wes Junker

Winter storm watch extended over entire region

ALERT: 1:15 p.m. - The Winter Storm Watch has been extended by the National Weather Service to cover the entire metro region Wednesday afternoon and night.

From 1:00 p.m. - For the first time this year, the models have been trending toward a snowier solution rather than a less snowy one as the storm approaches. The operational models take a potent upper level disturbance on an almost perfect track to deliver accumulating snow in the D.C. area.

The models still are swinging back and forth about the exact track/intensity of the storm, when a possible changeover from rain to snow occurs, and how much precipitation will fall. But they all indicate snow is likely to be falling by dark Wednesday and that the snow could come down quite heavily Wednesday evening through around midnight. This is potentially a short-lived, but intense event.

Right now it looks like the precipitation might start briefly as light rain or mixed precipitation in the immediate metro area (light snow or mixed precipitation north and west, see zone 2 map below) early Wednesday morning but would change to snow somewhere between 2 p.m. and 6 p.m. Wednesday. Precipitation during the morning - while capable of producing some slick spots in the normally colder suburbs will probably be more of a nuisance.

By evening, the storm has the potential to become significant and hazardous with wet snow that could lead to trees limbs coming down and power outages if the storm lives up to its potential. This is likely to be a heavy, wet snow with moderate winds developing late Wednesday night.

Keep reading for our initial accumulation assessment and some technical analysis...

ACCUMULATION ASSESSMENT

Below is a graphic indicating what we think the probabilities are for different amounts of snow. We will provide a more detailed and refined accumulation outlook later today. A good first guess would be 3-6" in Zone 1 and 4-8" in Zone 2, but you see the different possibilities. Upward or downward adjustments are certainly possible, if not likely.

snow-accum-012611.gif
Zone accumulation outlook.

Note: the dashed lines indicate the transition area between zone 1 and zone 2. Areas in that area are about equally likely to fall in either zone.

TECHNICAL ANALYSIS

The model runs based on data available at 7PM last night predicted anywhere from 0.75"(the GFS) to 1.25" (the European model) of liquid equivalent. The American models were colder in the low levels than the European model but it has a known bias of being too warm near and just above the earth's surface.

The later model runs from the U.S. models were not as aggressive in terms of precipitation, especially the NAM but it has been vacillating more than the other models. This morning's NAM trended back to a wetter snowier solution predicting more than an inch of liquid equivalent. That's why we indicate non-trivial probabilities of getting more than 8".

nam06-012611.gif

The 6-hourly precipitation forecasts from the NAM are shown above. The blue line on the image is the freezing line at around 5000 ft (850 mb). Note how even though one low tries to move east another hangs back along the coast at 1 a.m. Thursday as it responds to the strong mid-level circulation center that moves across our area. The strong dynamics and upward motion being forecast at the time when the heavy snow falls suggests there is an outside chance of thundersnow somewhere in the area. .

This morning's NAM was one of the more aggressive at changing the rain to snow quickly. It suggests rain at 1 p.m. on Wednesday but is clearly predicting snow by 4 p.m. The sounding (atmospheric profile from the surface through above cloud level) below shows the temperatures aloft at 4 p.m. being below freezing in D.C.

unstable-layer.jpg

The red line on the figure above (the sounding) gives you the vertical temperature structure of the atmosphere. On the figure, all the temperatures to the left of the slanted blue line are below freezing. The sounding has one other interesting feature. Right where the red line bends away from the blue line there is a weak unstable layer that does suggest there could be some convection - which could support thundersnow.

This morning's Canadian model (GGEM) has also come in wet and snowy and argues that this storm has the potential to produce a significant snowstorm. This model along with the NAM suggest that the winter storm watch that was posted for the western suburbs may be extended eastward to include the city and points east later this afternoon. This morning's GFS joined the dance and has a well-defined mid level circulation by 7 a.m. tomorrow morning aimed at our area. It argues for a changeover from rain to snow in D.C. around 4 p.m. but the changeover would occur first over the western suburbs where the precipitation could actually start as snow with the changeover working eastward towards Washington during the afternoon.

Bottom line: This storm the models are in rare agreement. This is looking more and more like a significant snowstorm.

(Capital Weather Gang's Jason Samenow contributed to this report, and received input from five other CWG meteorologists)

By Wes Junker  | January 25, 2011; 1:00 PM ET
Categories:  Forecasts, Latest, Winter Storms  
Save & Share:  Send E-mail   Facebook   Twitter   Digg   Yahoo Buzz   Del.icio.us   StumbleUpon   Technorati   Google Buzz   Previous: AM update: Winter Storm Watch for N & W suburbs
Next: PM Update: Thinking about tomorrow's snow

Comments

Very nice. Of course I continue to play skeptic to everyone around me who asks about it, replying that, "oh maybe an inch or two."

But privately, I hope it's a huge dump!

Thanks Wes and everyone else at CWG.

Posted by: ennepe68 | January 25, 2011 12:58 PM | Report abuse

FIRST!

Posted by: HaymarketDV | January 25, 2011 12:58 PM | Report abuse

First

God, I hate when people do it yet I just did

Posted by: Bious | January 25, 2011 12:58 PM | Report abuse

Would Charlottesville be considered zone 2?

Posted by: carrerascott | January 25, 2011 12:59 PM | Report abuse

I hereby hypothesis that my productivity in a given day is indirectly proportional to the number of CWG updates in that day.

Posted by: arcdfire | January 25, 2011 12:59 PM | Report abuse

SIGNIFIGANT SNOWSTORM?!!!! YAY!!!!!

btw, why does someone always have to yell, "first!" whenever a new post goes up??

Posted by: BobMiller2 | January 25, 2011 12:59 PM | Report abuse

WOO HOO! 45% CHANCE OF 8 in! Wow. Really happy!

Posted by: benzachr | January 25, 2011 1:00 PM | Report abuse

CWG - This forecast brings me much joy.

But if it busts I can look forward to getting my car washed & reading the outpouring of blame & angry postings here on CWG.

Posted by: FIREDRAGON47 | January 25, 2011 1:01 PM | Report abuse

Anagram for Jason Samenow: "Joe's a snowman."

Posted by: gardyloo | January 25, 2011 1:02 PM | Report abuse

First!

Posted by: getjiggly1 | January 25, 2011 1:02 PM | Report abuse

So in short... We still have no idea.. Thanks.

Posted by: ash10 | January 25, 2011 1:03 PM | Report abuse

Nice analysis.

Posted by: RepealObamacareNow | January 25, 2011 1:04 PM | Report abuse

YIPEE!! FINALLY!

Posted by: flynns2 | January 25, 2011 1:04 PM | Report abuse

Oh, gosh, oh gosh, oh gosh!!!!!!

**Bob starts hyperventilating**

I am loving this!!! Let it SNOW, let it SNOW, let it SNOOOOOOW!!!!!!!

I can't wait!!!!!!!!

Posted by: BobMiller2 | January 25, 2011 1:04 PM | Report abuse

Okay, so let me get this straight:

Either snow or a mix or plain rain depending upon where you are tomorrow morning. Transitioning to snow from North/West to South/East during the day, but not a heavy downfall. By tomorrow evening, all snow possibly everywhere and coming down quite hard?

If this is correct, a lot of folks will have decisions to make about work/school tomorrow. Yuck! But awesome too.

Posted by: authorofpoetry | January 25, 2011 1:05 PM | Report abuse

What bugs me is how "Accu"Weather still hates snow. 1.8 inches. Harsh. Even weather.com updated. (And now they say 4-8 for DC 25% of a foot of snow!) Anything AccuWeather knows that we don't?

Posted by: benzachr | January 25, 2011 1:06 PM | Report abuse

About 20th

Posted by: LoudounSouth | January 25, 2011 1:07 PM | Report abuse

Weather Channel still calls for a 90% chance of rain tomorrow and NWS has no winter storm watch for most of the area. At least they revised the high temperatures today from near 50 to the lower 40s. Keep it cold.

Posted by: rocotten | January 25, 2011 1:08 PM | Report abuse

Question regarding thundersnow....

How does the sounding posted in the article above compare with the soundings on severe wx days from last summer? In particular, the morning storm in July that roared out of MoCo into the District and exploded over us? I seem to recall a sounding was posted here for that event.

I am trying to see the feature on the temperature plot (red line) that indicates the instability. Is it the degree to which it diverges from the 0C line?

Posted by: ennepe68 | January 25, 2011 1:08 PM | Report abuse

Is there any chance you can put the accumulation map etc above the link fold as it took me a good 10 mins for the page to load and all I really wanted to see was the snow accumulation...

Thanks - and job well done.

Posted by: hereandnow1 | January 25, 2011 1:09 PM | Report abuse

Tomorrow's rush hour is going to SUCK. Doubt much will be canceled tomorrow if we're looking to get the most precip in the evening...

Posted by: visualglamour | January 25, 2011 1:09 PM | Report abuse

Where is the National Forecast Service's warnings? We have general model agreement for significant snowfall and yet there is no warning or watch for the District with less than 24 hours to go?

Posted by: BlusteryDCYankee | January 25, 2011 1:10 PM | Report abuse

CWG is very bullish on this one. Sorry snow haters you can't win them all.

Posted by: jbernard703 | January 25, 2011 1:11 PM | Report abuse

Nice! Excellent update and analysis.

Posted by: Bworl | January 25, 2011 1:12 PM | Report abuse

CWG is very bullish on this one. Sorry snow haters you can't win them all.

Posted by: jbernard703 | January 25, 2011 1:12 PM | Report abuse

I appear to be in the Euro's bullseye. Solid inch of qpf...Yay Loudoun!

Posted by: DullesARC | January 25, 2011 1:12 PM | Report abuse

TWC website is still a giant mess. Article on front page states 4-8 but forecast for 20009 still says rain. Guessing this will all look different in the next few hours. Hopefully the other local news outlets change forecasts appropriately for evening newscasts. When are the next bunch of models coming out??

Posted by: visualglamour | January 25, 2011 1:13 PM | Report abuse

Well, KRUZ, it looks like you're gonna have a heck of a night ahead of ya tomorrow.

btw, what the latest on the Euro model?

Posted by: BobMiller2 | January 25, 2011 1:13 PM | Report abuse

YYeeeHaawww, finally, here it comes! Bring on the snow!

Posted by: ShovelPlease | January 25, 2011 1:14 PM | Report abuse

Snow hater here.

Hoping Heat Miser sends a blast of warm air to turn this thing to rain ;-)

Posted by: BayouCowboy | January 25, 2011 1:14 PM | Report abuse

WSWatch for the whole area now!

Posted by: allagar | January 25, 2011 1:15 PM | Report abuse

TWC/NWS just put Arlington, Alexandria, Falls Church under WSW! its coming!!

Posted by: shirlingtonvillage | January 25, 2011 1:15 PM | Report abuse

Here's the WSW:
URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
109 PM EST TUE JAN 25 2011

DCZ001-MDZ010-011-013-014-016>018-VAZ036>039-050>057-502-260215-
/O.EXB.KLWX.WS.A.0002.110126T1900Z-110127T0900Z/
DISTRICT OF COLUMBIA-HOWARD-SOUTHERN BALTIMORE-PRINCE GEORGES-
ANNE ARUNDEL-CHARLES-ST. MARYS-CALVERT-NELSON-ALBEMARLE-GREENE-
MADISON-ORANGE-CULPEPER-PRINCE WILLIAM/MANASSAS/MANASSAS PARK-
FAIRFAX-ARLINGTON/FALLS CHURCH/ALEXANDRIA-STAFFORD-SPOTSYLVANIA-
KING GEORGE-SOUTHERN FAUQUIER-
INCLUDING THE CITIES OF...WASHINGTON...COLUMBIA...BALTIMORE...
ANNAPOLIS...WALDORF...ST MARYS CITY...CHARLOTTESVILLE...
CULPEPER...MANASSAS...MANASSAS PARK...FAIRFAX...ALEXANDRIA...
FALLS CHURCH...FREDERICKSBURG
109 PM EST TUE JAN 25 2011

...WINTER STORM WATCH IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH
LATE WEDNESDAY NIGHT...

THE NATIONAL WEATHER SERVICE IN BALTIMORE MD/WASHINGTON HAS
ISSUED A WINTER STORM WATCH...WHICH IS IN EFFECT FROM WEDNESDAY
AFTERNOON THROUGH LATE WEDNESDAY NIGHT.

* PRECIPITATION TYPE...BECOMING ALL SNOW DURING LATE AFTERNOON AND
EVENING.

* ACCUMULATIONS...5 OR MORE INCHES OF SNOW POSSIBLE.

* TIMING...SNOW STARTING DURING THE LATE AFTERNOON AND EARLY
EVENING. ENDING AFTER MIDNIGHT FROM SOUTHWEST TO NORTHEAST
WEDNESDAY NIGHT.

* TEMPERATURES...MID TO UPPER 30S WEDNESDAY...DROPPING TO THE
LOWER 30S BY THE EVENING. THE UPPER 20S WEDNESDAY NIGHT.

* WINDS...NORTHEAST 10 TO 15 MPH WEDNESDAY...BECOMING NORTHWEST
AROUND 15 MPH WEDNESDAY EVENING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT
SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL.
CONTINUE TO MONITOR THE LATEST FORECASTS.

&&

$$

Posted by: awshux | January 25, 2011 1:15 PM | Report abuse

ennepe68, the sounding is much different and only has a weak conditionally unstable layer where the slope of the temperature line is a little more slanted than the curved green line. Severe weather soundings are much more unstable and usually have a dry layer in the mid levels. One other aspect of the sounding above is the dry how he temperature and dewpoint lines separate a little above that layer which sometimes is a reflection that the convective parameterization scheme has kicked in. With such strong vertical motion and heavy precipitation that seems to be a reasonable guess.

Posted by: wjunker | January 25, 2011 1:16 PM | Report abuse

Thundersnow...just wondering how this affects my planned Wednesday a.m. Safeway and p.m. Ballston errands! At least tonight's dance looks okay.

This is starting to look like a rerun of the March, 1984 and Veterans' Day, 1987 events.

Posted by: Bombo47jea | January 25, 2011 1:17 PM | Report abuse

Sounds like we get some winter after all.

Posted by: jiji1 | January 25, 2011 1:17 PM | Report abuse

I'm curious about thundersnow? Is it like having a bad T-storm just with snow? Are we actually going to hear thunder? I live in Loudoun county BTW RIGHT next to IAD. Hearing the bullseye will be right on top of us.

Posted by: MVPlaya8120 | January 25, 2011 1:18 PM | Report abuse

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
109 PM EST TUE JAN 25 2011

DISTRICT OF COLUMBIA-HOWARD-SOUTHERN BALTIMORE-PRINCE GEORGES-
ANNE ARUNDEL-CHARLES-ST. MARYS-CALVERT-NELSON-ALBEMARLE-GREENE-
MADISON-ORANGE-CULPEPER-PRINCE WILLIAM/MANASSAS/MANASSAS PARK-
FAIRFAX-ARLINGTON/FALLS CHURCH/ALEXANDRIA-STAFFORD-SPOTSYLVANIA-
KING GEORGE-SOUTHERN FAUQUIER-
INCLUDING THE CITIES OF...WASHINGTON...COLUMBIA...BALTIMORE...
ANNAPOLIS...WALDORF...ST MARYS CITY...CHARLOTTESVILLE...
CULPEPER...MANASSAS...MANASSAS PARK...FAIRFAX...ALEXANDRIA...
FALLS CHURCH...FREDERICKSBURG
109 PM EST TUE JAN 25 2011

...WINTER STORM WATCH IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH
LATE WEDNESDAY NIGHT...

THE NATIONAL WEATHER SERVICE IN BALTIMORE MD/WASHINGTON HAS
ISSUED A WINTER STORM WATCH...WHICH IS IN EFFECT FROM WEDNESDAY
AFTERNOON THROUGH LATE WEDNESDAY NIGHT.

* PRECIPITATION TYPE...BECOMING ALL SNOW DURING LATE AFTERNOON AND
EVENING.

* ACCUMULATIONS...5 OR MORE INCHES OF SNOW POSSIBLE.

* TIMING...SNOW STARTING DURING THE LATE AFTERNOON AND EARLY
EVENING. ENDING AFTER MIDNIGHT FROM SOUTHWEST TO NORTHEAST
WEDNESDAY NIGHT.

* TEMPERATURES...MID TO UPPER 30S WEDNESDAY...DROPPING TO THE
LOWER 30S BY THE EVENING. THE UPPER 20S WEDNESDAY NIGHT.

* WINDS...NORTHEAST 10 TO 15 MPH WEDNESDAY...BECOMING NORTHWEST
AROUND 15 MPH WEDNESDAY EVENING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT
SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL.
CONTINUE TO MONITOR THE LATEST FORECASTS.

Posted by: BobMiller2 | January 25, 2011 1:18 PM | Report abuse

Yeah! The only bad thing from a life standpoint is the timing. I foresee lots of people driving to work tomorrow morning but being ill-prepared to drive in the snow causing an awful afternoon commute.

I'm hoping the continued analysis here helps me decide when to attempt the drive - before the PM rush or afterwards when there is more snow but fewer people on the road.

Posted by: biketraveller22 | January 25, 2011 1:20 PM | Report abuse

Rational advice: Deeeeep, cleansing breaths, people. We're still 24 hours away. Things could still change.

Irrational advice: Quick! Go get the TP now!!

Posted by: Juan-John1 | January 25, 2011 1:21 PM | Report abuse

WOOOOOHOOOOOO!!!!!
"the storm has the potential to become significant and hazardous with wet snow that could lead to trees limbs coming down and power outages"
AWWRIIIGGHHT!! That's what I'm talking about!!!!1111

It must be swell to be able to love snowstorms and, at the same time, ignore their consequences.

Posted by: dcreader6 | January 25, 2011 1:21 PM | Report abuse

This storm should make the snow lovers happy.

I would love to get excited about snowstorms around here, however, the power always goes out and people cannot drive in snowy conditions. It's more of a pain in the ass.

Posted by: bgaffney491 | January 25, 2011 1:23 PM | Report abuse

After somehow managing to survive last year's winter without a snow shovel (turns out lightweight cutting boards are pretty handy for shoveling snow off your car roof!), my husband and I finally bought one this fall. Glad we'll finally be able to put that puppy to use! Bring on the snow!

Thanks CWG for your excellent analysis, as always!

Posted by: serenefallschurch | January 25, 2011 1:24 PM | Report abuse

Schoolcast? Sounds like there's a good chance they'll be closed Wednesday, Thursday, and Friday too.

Posted by: pxl4 | January 25, 2011 1:25 PM | Report abuse

"possible"...."Potential".....I'm still not buying it...

Posted by: Pat_E | January 25, 2011 1:26 PM | Report abuse

CWG - A friend is getting married on Saturday in DC with family/friends coming into town on Friday. How will tomorrow's storm affect her plans, if at all? Thank you again for all the awesome forecasting.

Posted by: cassann981 | January 25, 2011 1:26 PM | Report abuse

Wes,
The 12Z ECMWF Numerical Printout for Dulles and DC are 1.07in. Greater QPF then the GFS and NAM .. do you give this higher amount any weight ?

Posted by: pseaby | January 25, 2011 1:27 PM | Report abuse

@cassann981

This shouldn't be a storm that takes days to recover from. The weekend should be ok.

Posted by: Jason-CapitalWeatherGang | January 25, 2011 1:28 PM | Report abuse

any school closing to report yet?

this what i feel like:
http://www.youtube.com/watch?v=0G8XH4WDxP4

Posted by: walter-in-fallschurch | January 25, 2011 1:29 PM | Report abuse

New to CWG this winter season, and definitely a little obsessed. Not only with their frequent updates, but I love reading everyone else's thoughts and opinions. My question is for CWG, hopefully you can answer this....How does this storm (and confidence level) compare to the Christmas weekend storm we totally missed? Christmas night they were calling for 6-10 inches, then we woke up and not so much as a dusting! What's different? Thanks :)

Posted by: elizabethk611 | January 25, 2011 1:30 PM | Report abuse

Wes, The ECMWF Numerical Print out for Dulles and DCA are both at 1.07in of precip from 12Z Wed - 12Z Thur. More then both the NAM and GFS. Do you give this any weight ?

Posted by: pseaby | January 25, 2011 1:30 PM | Report abuse

Pat_E, wait till there are tons of fat snowflakes falling on your head tomorrow. ;)

Posted by: Ian-CapitalWeatherGang | January 25, 2011 1:30 PM | Report abuse

Wes - right or wrong...you always provide an outstanding analysis of the odds and the key elements in these forecasts...I really enjoyed yet another post. Thanks! I'm still highly skeptical of this one...while hoping for a foot. KRUZ - Sorry man, for your sake, only, I hope for rain.

Posted by: parksndc | January 25, 2011 1:32 PM | Report abuse

Yay Bring on the "ThunderSnow" when I shouted that in CBS 9 chat-room last year..people "Boo'ed" me and said I did not want it! yes! I do! that's jackpot SNOW! whoo hoo!

Posted by: 882181 | January 25, 2011 1:32 PM | Report abuse

No comments in 6 minutes... This is sad! 5+.... luv it!

Posted by: benzachr | January 25, 2011 1:32 PM | Report abuse

Im with @Pat_E

im not buying and really hope for a bust. it feels like dec. 26th deja vu! i know its gonna snow alot, but id love to see the warm air win out and the tools err models be wrong in the end, especially east of DC inside the beltway!

Posted by: KRUZ | January 25, 2011 1:33 PM | Report abuse

RE: New zone accumulation map - Now that feeds my data driven nature. Thanks...

Posted by: djm-01 | January 25, 2011 1:33 PM | Report abuse

No one at work believes me when I say we are going to get snow tomorrow.

Posted by: Snowlover2 | January 25, 2011 1:33 PM | Report abuse

thundersnow is just snow accompanied by thunder and sometimes happens when you have such a dynamic system as this one. We may or not get thundersnow but it is a possibility.

I think the nam and euro have very similar QPF amounts with the gfs being slightly lower. I expect at least 0.80" for what that is worth. Most systems with such a track produce that much precipitation

Posted by: wjunker | January 25, 2011 1:35 PM | Report abuse

OK, so I live in Sterling but work in Bethesda. I imagine I'd be OK going to work in the morning, but how about later in the day? Should I prepare myself for a treacherous ride or should I perhaps leave earlier than my 6pm closing time? Advice? Oh, and I drive.

Posted by: eunicedelrosario | January 25, 2011 1:35 PM | Report abuse

Accuweather has 2-5 for DC. TWC now is saying 4-8 for DC...other outlets are following the Gang...you heard it here first!

Posted by: parksndc | January 25, 2011 1:36 PM | Report abuse

Thanks Wes regarding t-snow.

With words like "convective parameterization scheme" you can just take me on the kitchen table.

That said, I might have to telecommute tomorrow just to see if we have any rumbles out in central Fairfax.

Posted by: ennepe68 | January 25, 2011 1:36 PM | Report abuse

Thanks Wes regarding t-snow.

With words like "convective parameterization scheme" you can just take me on the kitchen table.

That said, I might have to telecommute tomorrow just to see if we have any rumbles out in central Fairfax.

Posted by: ennepe68 | January 25, 2011 1:38 PM | Report abuse

Wes, Jason, et al, thanks for keeping us updated. Looking forward to seeing how all of this plays out tomorrow! When do y'all head back from the AMS conference?

Posted by: jaradel | January 25, 2011 1:38 PM | Report abuse

@MVPlaya8120:

Yes...it's basically a thunderstorm with snow...occasionally with snowbursts dropping one to as much as FOUR inches per hour!

Happens on occasion in the Great Lakes or mountainous areas such as the Rockies, Cascades or Sierra Nevada.

Around here, thundersnow events tend to occur when temperatures are just below freezing and there is powerful very deep or rapidly intensifying low pressure. Basically what's needed is a trigger for rapid violent convection, something which is rather rare during the winter months.

Actually snow and/or ice crystals are a prerequisite for ALL lightning formation or cloud electrification during thunderstorms. The difference during the summer months is that the snowflakes and ice crystals are generally four to eight miles above our heads during the warm season, so that when they fall, the warmer air underneath melts them to rain before they reach the ground. During the winter, the lack of sufficient convective triggers generally inhibits thunderstorm formation. Occasionally violent convection in winter can be induced by rapid storm intensification [bombogenesis], lake-effect forcing from warmer water underneath, sudden frontal lifting or orographic forcing when moist air flows over a mountain range. The result of sudden violent convective forcing with temperatures below freezing is thundersnow.

Posted by: Bombo47jea | January 25, 2011 1:40 PM | Report abuse

@elizabethk611

This storm is different from the Christmas storm because we're not on the edge of the precipitation. It would be much harder for this one to miss us. The main thing that could cause this storm to underperform would be temperatures that would be too warm bringing more rain in some spots. But guidance has been trending colder. Still a close call especially from DC east.

Posted by: Jason-CapitalWeatherGang | January 25, 2011 1:40 PM | Report abuse

So, if we're looking at a total of about 0.80" to 1.00" liquid equivalent, how much of that is likely to fall as rain during the opening volley? I mean are we looking at half an inch of rain followed by 3 to 5 inches of snow, or is most of that likely to come down as snow?

Also, does the fact that it is "wet" snow mean that you get fewer inches of snow per inch of liquid equivalent?

Posted by: wappledoo | January 25, 2011 1:41 PM | Report abuse

Wes and CWG - thank you so much for the update and all of your hard work!
Walter - LOL at Linus and Lucy! Great way to describe the feeling! Hope you get tons of snow for sculpting.

Posted by: kathyb39 | January 25, 2011 1:41 PM | Report abuse

@ennepe68 -Funny you should mention that. I just took one of those!!!!!!

Posted by: jwash4472 | January 25, 2011 1:42 PM | Report abuse

47 in Gaithersburg :(

Posted by: snowstalker | January 25, 2011 1:42 PM | Report abuse

@wappledoo

Great question. The farther west you are in the metro region, the more of that 0.8 liquid which is in the form of snow. But this is where the greatest uncertainty probably is.

And yes, that it's going to be a wet snow does mean you get fewer inches of snow per liquid equivalent. Not only that, but the relatively warm ground will initially cut back on how much snow per unit of liquid equivalent. But as the snow increases in intensity and temps drop, the ratios go up. Wes is actually an expert on this stuff, so I'm hoping he can elaborate.

Posted by: Jason-CapitalWeatherGang | January 25, 2011 1:46 PM | Report abuse

Wes et al--really appreciate your efforts. Also, the sounding forecast with explanation is really helpful. It looks like the skew-T chart I used to study in aviation weather. Thanks again!

Posted by: petworthlad | January 25, 2011 1:47 PM | Report abuse

question for CWG...when is the precip expected to become real light/end. After midnight tomorrow?

Posted by: BH99 | January 25, 2011 1:47 PM | Report abuse

Will roads be effected? Haven't they warmed up?

Posted by: teach1 | January 25, 2011 1:48 PM | Report abuse

My models are still showing 2" for Springfield & Lorton and areas along I-95 south and east of DC!
(I am really hoping my models are wrong!)

Posted by: Firedude | January 25, 2011 1:48 PM | Report abuse

My excitement is palpable. As Bob Costas said in Baseketball: you should feel these nipples.

Sorry for the inappropriateness, but in this case I can't help but feel it's warranted.

Posted by: bbirnbau | January 25, 2011 1:49 PM | Report abuse

Will roads be effected? Haven't they warmed up?

Posted by: teach1 | January 25, 2011 1:49 PM | Report abuse

It's going to be awesome when everyone's wrong and we get 12 inches of snow. I can't wait.

Brian and VA - want to skip work Thursday, have some homemade Pho and build snow forts? I've got tons of TP at my house, don't worry.

Posted by: C-Dizzle | January 25, 2011 1:52 PM | Report abuse

@teach1

Yes- as temperatures drop late Wed afternoon and Wed night and snow increases in intensity, snow is likely to accumulate on roads despite the fact they will have warmed some today.

Posted by: Jason-CapitalWeatherGang | January 25, 2011 1:53 PM | Report abuse

A number of the local newscast are still indicating that the snow will not stick on the Raodways just on the grass. Is this true ?

Posted by: snow_lover_9002 | January 25, 2011 1:54 PM | Report abuse

@teach1 & Jason,

Also, since we're probably getting some rain first, any pre-treatment of the roads might be washed away, huh?

Posted by: wappledoo | January 25, 2011 1:54 PM | Report abuse

It won't matter if the roads are just wet or covered in snow, the mere sight of snow flakes will send DC area drivers into a panic resulting in massive delays during the evening rush tomorrow. I am anticipating a 2 hour + commute from DC to Springfield/Lorton tomorrow if the roads are just wet and its snowing. A 3 hour + commute if there is any snow on the roads at all.

Posted by: Firedude | January 25, 2011 1:55 PM | Report abuse


I find it interesting that roads will be so warm. It was below freezing for 3 days. Ground is a solid, it holds more energy than air, and would take longer to heat up or cool down. There is some sun out today, so I guess that helps. But temperatures will also go back below freezing tonight, which would coo them some also.

Posted by: apeirond | January 25, 2011 2:01 PM | Report abuse

the amount that snow accumulates depends on lots of various things, ground temperature, snowflake type and size. These flakes should be large aggregates (large is good) but also probably have a decent amount of riming and water content (wet flakes,which is bad for getting high ratios) especially during the 1st half of the snowfall. I'd guess that ratios would be below 10-1 but that's strictly a guess. Much depends on how hard it snow and how much the surface temperature cools which may vary across the region. I would guess the ratios would be highest to the west and lowest to the east.

Posted by: wjunker | January 25, 2011 2:03 PM | Report abuse

sounds like at least 3" for DC...and perhaps as much as 8". Hopefully we get the latter!!

Posted by: BH99 | January 25, 2011 2:04 PM | Report abuse

&dcreader6 - "It must be swell to be able to love snowstorms and, at the same time, ignore their consequences."

Its tough to admit, but true.

Posted by: jiji1 | January 25, 2011 2:04 PM | Report abuse

from the 5am forecast "the mid-to-even upper 40s today are going to feel really nice." -- and at 2pm: DCA 43, BWI 43, IAD 43.

Posted by: manatt | January 25, 2011 2:07 PM | Report abuse

Can anyone remind me who made the awesome snow sculptures from last year? Were they over off Duke near King Street Metro? Also remember some pics of some in a yard. Hoping we'll get enough snow this year to see them again!

CWG-thanks for the details! Keep it up!

Any thoughts on Thursday morning...unfortunately OR's don't usually have delayed openings for weather...no time off for weather!

Posted by: motherrunner | January 25, 2011 2:08 PM | Report abuse

Are Washington and Frederick Counties in Maryland so far west that they could actually see less snow than DC?

Thanks CWG

Posted by: msmith2131 | January 25, 2011 2:08 PM | Report abuse

True, Firedude, but at least a bunch of people with few responsibilities can run around and play in it.

Posted by: SouthsideFFX | January 25, 2011 2:08 PM | Report abuse

I believe some winter weather forecasts made back in November indicated that we'd probably get 1 snowfall this winter of the size this one is forecast to be, and several smaller ones similar to what we've gotten thus far.

Did CWG make a similar type forecast? I can't recall.

Posted by: ThinkSpring | January 25, 2011 2:09 PM | Report abuse

OH MY GOD!!!!!!!! :0

Posted by: justin032 | January 25, 2011 2:10 PM | Report abuse

definitely want 'snowflakes with a decent amount of riming"

Posted by: jiji1 | January 25, 2011 2:11 PM | Report abuse

I am on the edge of the zone 2 line is northern Stafford County....What are the odds of the line shifting a little south east and I become a Zone 1?????

I have my fingers crossed!! I was listening to B101.5 on the radio and they are saying less than an inch and mostly rain...I think they are TRYING to bust my bubble!!!

Posted by: Hopin4Snow | January 25, 2011 2:14 PM | Report abuse

Will bring heavy weather gear with me to work tomorrow. Must be prepared to shove several inches of wet slushy snow off of car, while standing in several inches of wet slushy snow, while wet slushy snow comes down hard all around me.

Ya'll ready?
This *might* be the most significant snowfall of the winter, so be prepared to make the most of whatever you want to do with it.

Posted by: FIREDRAGON47 | January 25, 2011 2:15 PM | Report abuse

I see on the NWS Snowfall Total Prediction, they have pretty decent snow across DC if I'm reading the color/chart right about 6-7 Inches... Here is the Link:

http://www.erh.noaa.gov/er/lwx/winterstorm/

Posted by: Michael_Nguyen | January 25, 2011 2:16 PM | Report abuse

THUNDERSNOW!!! All my models also indicate a high probability of ball lightening!

Posted by: GD1975 | January 25, 2011 2:16 PM | Report abuse

@CWG: Any comments on not getting up to the forecast highs for the day? I'm at 36 here in Annapolis (2pm) but our forecast high was 44.

I'd anticipate that works in our favor for more snow in Zone 1. The 10am update did mention that perhaps the accumulations east of I-95 would trump those to the west but that seemed to have changed by the time the Zones went up.

Posted by: annapyr | January 25, 2011 2:17 PM | Report abuse

Why can't I read your blog on my Blackberry? It's all white space on the left and just a little text on the right?

Posted by: BusyMom1 | January 25, 2011 2:20 PM | Report abuse

Looking at 2pm obs, forecasted temps thru most of the region look to be on track. Jackpot is Stafford, Spotsylvania, Fauquier, and Culpeper counties with temps in the low and mid 50's.

DCA and IAD at 43 now, so mid 40's is on target.

Posted by: ThinkSpring | January 25, 2011 2:21 PM | Report abuse

BusyMom1 - I have the same problem. And our blog has limited capability but Washington Post is working on it. Best to browse us in Internet Explorer. Regret the limitations!

Posted by: Camden-CapitalWeatherGang | January 25, 2011 2:22 PM | Report abuse

According to the Weather Channel, DC itself is said to get 4-8" with 25% chance of a foot (New York gets the same.)

When you click onto Weather.com, the first headline you see now is "DC, Baltimore may get hit hard", which whether you like it or not is a definite change from so far this season when Philly/NY/Boston got hit hard and DC/MD/VA got a glancing blow at most.

Posted by: mkarns | January 25, 2011 2:23 PM | Report abuse

BusyMom1 - change the view on your Blackberry to "Column" and it should center the page for you. That works for me, but the Blog site is REALLY slow to load on my Blackberry

Posted by: MDDem2 | January 25, 2011 2:23 PM | Report abuse

@Michael_Nguyen, that map is experimental and literally changes every 5 minutes... not to be trusted

Posted by: finger11 | January 25, 2011 2:23 PM | Report abuse

What shall I drink tomorrow before going sledding? Hmmm.....

Posted by: bbirnbau | January 25, 2011 2:24 PM | Report abuse

looks like 6" line from NWS snowfall forecast just grazes me in Berwyn Heights. Not a huge snowfall, but will be pretty happy if we get it. When exactly does snow end??

Posted by: BH99 | January 25, 2011 2:24 PM | Report abuse

I wish i knew what all the other charts meant!!!! I'm crossing everything I've got that we get dumped on!!!

Posted by: pgcoresident | January 25, 2011 2:24 PM | Report abuse

I experienced the most amazing thundersnow when living in Moscow. Driving winds, white out, snow practically raining past the window and THUNDER AND LIGHTENING. Lasted about 20 minutes and then went back to regular, light snow. It was amazing! I think thundersnow is kinda cool (when I watch from inside). I'll keep an ear out tomorrow.

Posted by: beta1 | January 25, 2011 2:25 PM | Report abuse

Of course, if you click the text details link for DC on TWC you get something that talks about almost all rain and little or no accumulation.

I guess the update the website one page at a time!

Posted by: MDDem2 | January 25, 2011 2:29 PM | Report abuse

I know it is still way out and would depend on # of inches, but any guesses on flights out of DCA on Thursday morning?

Posted by: purps | January 25, 2011 2:31 PM | Report abuse

@ finger11

Thanks for the Info... :)

Posted by: Michael_Nguyen | January 25, 2011 2:31 PM | Report abuse

I have begun to spread the news and the office is all atwitter. I also got some of my colleagues checking out the CWG blog with the caveat it gets addicting and fast. Thanks guys!

Posted by: mjwies11 | January 25, 2011 2:32 PM | Report abuse

@motherrunner, regarding your question on the snow sculptures, the ever-talented "walter-in-fallschurch" who frequents CWG is the man behind the snow sculptures built in his (presumably) Falls Church yard. Not sure about the person(s) behind the Alexandria snow sculptures...

Posted by: ToBeBlunt | January 25, 2011 2:32 PM | Report abuse

We will continue to attempt updates with any new information but I would trust Wes & Jason with their interpretation of the data. Their forecasts have had more skill than other outlets this Winter.

Posted by: Camden-CapitalWeatherGang | January 25, 2011 2:33 PM | Report abuse

@ finger11

Thanks for the Info... :)

So tell me something I see TWC has us a 25% for FOOT of SNOW, but Philadelphia is at 33%, but New Cork City is at 25%.... Why is Philadelphia higher then New York??

Posted by: Michael_Nguyen | January 25, 2011 2:33 PM | Report abuse

Its eems now most the forecasters seem to be agreeing now that we are goona see some signifigant snow all around DC. Accuweather was the last one who had not got on board the last time i checked.

Posted by: BradFinWoodbridgeVA | January 25, 2011 2:34 PM | Report abuse

Expect a lot of delays and cancellations wed night-thursday morning. Well, I hope planes wont be flying over my house during THUNDERSNOW!!

Posted by: MVPlaya8120 | January 25, 2011 2:35 PM | Report abuse

@bbirnbau - I would suggest an Irish Coffee - a little caffeine mixed with booze is the perfect combo for sledding.

Posted by: C-Dizzle | January 25, 2011 2:35 PM | Report abuse

mjwies11 - thanks so much. Appreciate your following us. We strive to be the best at forecasting the tricky DC weather-- that is what a local blog with meteorologists should be about, yes? :)

Posted by: Camden-CapitalWeatherGang | January 25, 2011 2:35 PM | Report abuse

Wheeeeeeeeee! Thundersnow! (Said as a native Floridian who grew up with thunderstorms and finds them soothing...)

Think I will just telecommute tomorrow and that way not have to worry about the folks on I-66. (Much safer that way...)


Kim in Manassas

Posted by: ksrgatorfn1 | January 25, 2011 2:36 PM | Report abuse

When will the first Winter Storm Warnings be issued?

Posted by: BobMiller2 | January 25, 2011 2:39 PM | Report abuse

MD State Highway Administration will NOT be pre-treating since storm is expected to begin as rain or mix. Thanks, CWG for all your hard work.

Posted by: MDSHA | January 25, 2011 2:40 PM | Report abuse

AccuWeather is also having trouble putting up a number. They usally have the total snow predicted up on the top bar, but they cheap out and say, Asthma is Down Today.

Posted by: benzachr | January 25, 2011 2:40 PM | Report abuse

Thundersnow sounds like a monster truck event held at the armory.

(using a deep voice)
THUNDERSNOW
THUNDERSNOW
THUNDERSNOW
THUNDERSNOW
THUNDERSNOW

Posted by: mscofield1 | January 25, 2011 2:40 PM | Report abuse

@msmith2131

Good question about Frederick and Washington Co. You might not get the heaviest precip, but because it's colder there, will accumulate better. If the storm tracked a bit east of where currently forecast, yes- there is the possibility you'd just get a little snow.

Posted by: Jason-CapitalWeatherGang | January 25, 2011 2:41 PM | Report abuse

@ksrgatorfn1

I know what you mean! I'm also a native Floridian who misses the 2-3pm summer storms. Nothing beats napping in a hammock inside a protected porch during one of those storms.

I've never experienced thundersnow, but I'm excited, too! [oh, and guessing based on your username, go gators! ;-)]

Posted by: wappledoo | January 25, 2011 2:41 PM | Report abuse

Okay so this patient grasshoppa did some work the last 1.5hrs and swore off the blog, instead of hitting RE-FREAKING-FRESH every 10 seconds...and lo and behold i come back to see my area is zone one...i love the zone diverders. Helps non-techie's like me very much!

Posted by: lisajulia | January 25, 2011 2:41 PM | Report abuse

CWG:

Since HEAVY SNOW forecast are we expecting blowing and drifted snow, well any wind associated with this storm??

Posted by: Michael_Nguyen | January 25, 2011 2:42 PM | Report abuse

Okay so this patient grasshoppa did some work the last 1.5hrs and swore off the blog, instead of hitting RE-FREAKING-FRESH every 10 seconds...and lo and behold i come back to see my area is zone one...i love the zone dividers. Helps non-techie's like me very much!

Posted by: lisajulia | January 25, 2011 2:42 PM | Report abuse

Accuweather says 1.6 inches for Burtonsville, down from 1.8 inches earlier this morning.

Whatever...

Posted by: MDDem2 | January 25, 2011 2:43 PM | Report abuse

I remember thunder in the early morning hours of the first February storm last year. It was kind of eerie, actually.

Posted by: weatherwatcher1 | January 25, 2011 2:44 PM | Report abuse

Micheal_Nguyen, at the onset, the snow will be pretty heavy and wet so blowing/drifting won't be prevalent. Towards the end it may dry out a bit and winds pick up but nothing that would be too significant.

Posted by: Brian-CapitalWeatherGang | January 25, 2011 2:45 PM | Report abuse

@ MDDem2

I believe Accuweather haven't updated or recieved any of the latest models, If I'm understanding

Just about everyone well get a decent snowfall...

TWS = 4-8 Inches
CWG = 3-6/4-8 (Pending on where you live)
Other outlets are oin the same page with CWG/TWC as of now..

Posted by: Michael_Nguyen | January 25, 2011 2:47 PM | Report abuse

Any possibility of no school tomorrow, or an early closing, at minimum?

Posted by: BG347 | January 25, 2011 2:48 PM | Report abuse

Has anyone else noticed how close the outskirts of the storm are to the area? Any chance this thing arrives early before the cold air reinforcements and screws all of this up?

Posted by: homertuckumd | January 25, 2011 2:51 PM | Report abuse

Has anyone else noticed how close the outskirts of the storm are to the area when looking at the radar? Any chance this thing arrives early before the cold air reinforcements and screws all of this up?

Posted by: homertuckumd | January 25, 2011 2:51 PM | Report abuse

CWG..

At the time can we at least say this aint gonna be a bust??

I dont care about super totals..just want enough to take the boy sleding thursday morning..

Posted by: BradFinWoodbridgeVA | January 25, 2011 2:52 PM | Report abuse

capital weather gang

if you are looking for feed-back on your storm data presentation, here it is: GREAT i love the late-night blogs, very nice for people who wish they could do more than see "pretty colors" when they look at a model... ALSO, i find your zone forecasts to be FAR more comprehensible than "OH.. NORTH-WEST-ISH...".... GREAT JOB!!!
anyway this turns out, you'll have at least one happy reader here.

Posted by: SnowDreamer | January 25, 2011 2:52 PM | Report abuse

National - 3 inches
IAD - 4.5
Balt - 7

Posted by: FIREDRAGON47 | January 25, 2011 2:54 PM | Report abuse

NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO!!!

Posted by: B-rod | January 25, 2011 2:55 PM | Report abuse

@ Camden-CapitalWeatherGang

Yes!

You guys rock!

Posted by: mjwies11 | January 25, 2011 2:56 PM | Report abuse

@Michael_Nguyen

The accuweather local forecast (even on the professional site) is bordering on irresponsible at this point. They have 1.9 inches forecasted for our area and probably less south. Given all the model data and consensus, that needs to be updated. Many people depend on those local forecasts as opposed to models and boards such as this one.

Posted by: DLO1975 | January 25, 2011 2:56 PM | Report abuse

i don't know who made that "car in a parking space" sculpture in alexandria last year. i really liked that one. what a great idea... the other "great idea" one i saw last year was the "2 feet of snow"...on a city street somewhere. oh, i wish ida thought of that!

i am so dreading the next round of model runs. i don't see how they could get much better. the track is almost perfect. i love how it "goes blue" right over us. there's a moment there where we're the best place for snow in the country.

Posted by: walter-in-fallschurch | January 25, 2011 2:57 PM | Report abuse

WUSA Channel 9...

For DC, we're likely to see 1"-3" of accumulation by Wednesday night with 3"-6" in our northern and western suburbs from Gaithersburg to Fairfax. There will be some places from Frederick to Leesburg back to the Blue Ridge that could pick up 6"-8" or more. There is also the potential that the heavier snow bands could impact areas south of town and with that, The NWS has issued a Winter Storm Watch for the entire area for Wednesday and Wednesday night.

WJLA Channel 7...

We're now tentatively predicting a more significant snowfall tomorrow with 4 to 7 inches north and west of the city, and 2 to 5 in the city, and south and east.

WRCTV Channel 4...

Right now the indications are that we could get 1-3 inches of snow around the D.C. metro area and 3-6 inches west and north of Washington before ending late Wednesday night.

Posted by: Showmethesnow | January 25, 2011 2:57 PM | Report abuse

@Michael_Nguyen... STOP reading/watching TWC. Their site is updated by computers. Updates are not timely. They were completely clueless about our little area until a couple of hours ago. You've got to rely on the CWG guys or live folks on the internet at this point. Pretty soon, we just sit back and watch the radar and hope for the best, depending on whatever outcome you're looking for.

Sorry to be one of those folks who tells others what to do. I normally don't do that. But I've noticed your frustration with lack of agreement among the various media outlets and wanted to chime in. Remember at this point we are about 24 hours away from the meat of the storm.

Posted by: lingering_lead | January 25, 2011 2:58 PM | Report abuse

pretty cool that the Maryland State Highway Department posted a comment! Looks like they're getting their weather from the best source around!

Posted by: bachaney | January 25, 2011 2:59 PM | Report abuse

Joe Bastardi just had the following as part of his tweet. Wes, do you think this is plausible? Seems high to me.

Dc 6 nw subs 12 bwi 6 nw subs 12

Posted by: Aaronj629 | January 25, 2011 2:59 PM | Report abuse

CWG

Sorry i meant to say as of now is it safe to say this storm will at least not be a total bust ( All rain/or heads to sea.) ?

Posted by: BradFinWoodbridgeVA | January 25, 2011 2:59 PM | Report abuse

I don't think schools close to the District will close tomorrow, but my kids would be delighted w/an early dismissal. And if the timing moves up so that we expect snow in the PM, that seems likely.

What's interesting is that so far WTOP isn't pushing this--it's not the top story or anything like that. Are other media doing the same? Did the December 26 failure scare them off?

Either way, I've already been to the grocery store for whatever I might need tomorrow and Thursday and I'm risking jinxing things by asking my husband to get my cherished old Flexible Flyer sled from storage. But I'll take the risk rather than risk the wrath of my 11 year old if the snow comes and she can't go sledding!

Posted by: concepcion611 | January 25, 2011 2:59 PM | Report abuse

Wow...locals are being very conservative. If DC ends up with 6-12 there will be some answering to do. Although my guess is they are just waiting on tonight's models to tell them what to do in terms of #s.

Posted by: DLO1975 | January 25, 2011 3:00 PM | Report abuse

@ksrgatorfn1 and Wappledoo- I'm a Floridian and a Gator as well-fingers crossed we get thundersnow- and that I'm awake to experience it :)

Posted by: Snowlover2 | January 25, 2011 3:01 PM | Report abuse

Seems like TV mets are sloooowwwllyyy trying to make themselves look better.

Posted by: MVPlaya8120 | January 25, 2011 3:01 PM | Report abuse

I would have posted Fox 5 but I did not see a total accumulation prediction for them. Probably smart on their part.

Posted by: Showmethesnow | January 25, 2011 3:04 PM | Report abuse

I'm waiting for someone to notice the new Canadian has us in the 1.5-1.75 QPF area, all below freezing. UH OH.

Posted by: 4seamed | January 25, 2011 3:06 PM | Report abuse

Uh Oh as in good uh oh if we are looking for snow though....

Posted by: mandarb77 | January 25, 2011 3:08 PM | Report abuse

Uh Oh as in good uh oh if we are looking for snow though....

Posted by: mandarb77 | January 25, 2011 3:09 PM | Report abuse

I LOVE the CWG and subsequent great commentary - thanks for all your hard work CWG (and everyone else's input!). I'm a relative newbie to weather stalking, so when do the new models come out?

Posted by: Myndiera | January 25, 2011 3:10 PM | Report abuse

I am really liking the NWS snowfall accumulation map. 7" where I am! Hooray for snow!

http://www.erh.noaa.gov/er/lwx/winterstorm/images/StormTotalSnow.png

This is an interesting blog post on tbd.com:

http://www.tbd.com/blogs/weather/2011/01/several-inches-of-snow-looks-likely-as-storm-hits-d-c-wednesday-7662.html

ABC7 Meteorologist Alex Liggitt says, "Yeah, the potential is there for an isolated clap of thunder tomorrow evening in the heaviest snow bands.

and Bob Ryan says, "Leaving day early from SEA to get back to DC," Ryan tweets. "Can't chance IAD cancellations with PM snow+ possible Wed.

Posted by: BobMiller2 | January 25, 2011 3:13 PM | Report abuse

@MVPlaya8120: That's exactly what the TV mets are doing, that way it doesn't look like they busted. (Like no one will notice they're going from "mostly rain" to "1-3" to "3-6" and hopefully more). Also, they love to say things like "keep checking back with us as all the details are not yet in" when, in fact, the details are mostly in at this point!

Posted by: petworthlad | January 25, 2011 3:15 PM | Report abuse

Went to the store and hear WTOP on the radio..your correct..WTOP seems to be downplaying it pretty well..the forecast is pretty brief and general..rain and SOME snow for WED is all there saying....HMMMM...

Maby there a little gun shy after the last few events.....

Posted by: BradFinWoodbridgeVA | January 25, 2011 3:15 PM | Report abuse

Posted by: MVPlaya8120 | January 25, 2011 3:16 PM | Report abuse

"Dc 6 nw subs 12 bwi 6 nw subs 12"

That's from Bastardi? Sounds like Accuweather can't get even internal agreement. They say "1.8 inches of snow on the way" for Baltimore and "0.57 inches of rain on the way" for DC, plus "A little snow ending in the evening, accumulating a coating to an inch."

Posted by: mkarns | January 25, 2011 3:16 PM | Report abuse

"QPF" [something] per foot?

Posted by: tws1372 | January 25, 2011 3:18 PM | Report abuse

Sorry for the dopey question but does "heavy snow" mean big wet flakes, or lotsa snow coming down very fast, or both?

Posted by: mcaicedo | January 25, 2011 3:18 PM | Report abuse

@BobMiller2--interesting that Bob Ryan is coming back. I did think Doug Hill looked a little lonely last night! I wonder if Topper is headed back too. Seems like they really need some leadership in the WUSA wx dept.

Posted by: petworthlad | January 25, 2011 3:18 PM | Report abuse

Topper Schutt just tweeted...

Winter Storm Watch N & W of DC. I think DC, Howard & Fairfax counties shoulkd be included. 4" - 8" 3PM - 10PM Wed.We'll tell you where @ 5PM

Posted by: lingering_lead | January 25, 2011 3:18 PM | Report abuse

THIS JUST IN: NWS HAS POSTED AN ACCUMULATION FORECAST FOR WEDNESDAY NIGHT!!!!

4-8" in the district
5-9" IAD
6-10" Gaithersburg/North Potomac

BRING IT ON!!!!!!!

Posted by: SnowDreamer | January 25, 2011 3:18 PM | Report abuse

@tws1372: QPF=Quantitative Precipitation Forecast

Posted by: petworthlad | January 25, 2011 3:20 PM | Report abuse

For the people that are saying some forecasts are off and not updated, you have to realize that a lot of sites do not manually update their forecasts with the frequency that users @CWG check them. Users here are constantly checking forecasts every minute -- you can't expect them to update that quickly.

In time they will all start to line up with one general forecast - SNOW

Posted by: dmackerman6226 | January 25, 2011 3:21 PM | Report abuse

The 18Z nam pretty much stayed the course forecasting around an inch of liquid equivalent across the area but predicting .75 across the western suburbs in a 6 hour period. It also suggests that west of the city almost all the precipitation will fall as snow.

Posted by: wjunker | January 25, 2011 3:23 PM | Report abuse

UH OH as in models keep trending higher, with one of them spitting out 15-17 inches (if using a straight 10-1 ration for an all snow event, which it shows) and even the new EURO coming around to the colder, snowier conclusion the rest of them are coming to. Japanese also shows over 1 inch (10 inches using same criteria above) and colder event.

New NAM (just in as of 320 pm) shows a convective band of INTENSE proportion over us at midnight, with a total QPF of 1-1.25 inches over the entire area. No wonder tv mets have taken their accumulation totals off the board- they can't keep up since they keep going up with every model run!

Posted by: 4seamed | January 25, 2011 3:24 PM | Report abuse

@tws1372--QPF is quantitative precipitation forecast, always reported in liquid water equivalent. Convert to snow using a typical 10:1 ratio---eg .5 inches qpf = 5 inches snow.

Posted by: annapyr | January 25, 2011 3:25 PM | Report abuse

An airport question for you - what are my odds looking like for a 7 AM Thursday flight headed south out of National? Thanks for all the data, very helpful as always.

Posted by: johnsonshome | January 25, 2011 3:25 PM | Report abuse

TWC has brought up DC a little more these past few forecast.....This morning they didnt even mention us...it was about boston a Philly...funny aint it..

When they send Cantore to Dc tonight( if they do) you know we might get something..LOL!!

Posted by: BradFinWoodbridgeVA | January 25, 2011 3:29 PM | Report abuse

good grief. my son is supposed to have eye surgery at Walter Reed on Thursday. we live 2 hours away. anyone know of a good, safe hotel near WR??

Posted by: ounanm1 | January 25, 2011 3:30 PM | Report abuse

Looking forward to watching the TV guys/gals bob & weave at 5pm!

Posted by: petworthlad | January 25, 2011 3:30 PM | Report abuse

The 18z NAM is great news for snow lovers!

Posted by: BobMiller2 | January 25, 2011 3:32 PM | Report abuse

@BobMiller2--interesting that Bob Ryan is coming back. I did think Doug Hill looked a little lonely last night! I wonder if Topper is headed back too. Seems like they really need some leadership in the WUSA wx dept.

*****************************

Unfortunately, other than Topper, the WUSA weather department is not what it used to be. I heard from a reliable source that the new news director this past year felt that the weather team had too many white men, which is why Devon Lucie was booted out and Anny Hong (who is okay, but not great) came aboard. It looks like they are only sticking with three people on their team (Topper, Anny and Howard), so hopefully no one ever gets sick or wants to take a vacation. Sad that some people feel that race/gender is more important than actual qualifications. Anyway, it wouldn't surprise me to see Topper come back - I think it was two or three years ago when he bailed out of a family vacation in Colorado to come back and cover a winter storm.

Posted by: thepostischeap | January 25, 2011 3:34 PM | Report abuse

I demand light, fluffy snow!

CWG
Awesome reporting. You merit an award for your responsiveness and expert analysis.

Posted by: moo1 | January 25, 2011 3:35 PM | Report abuse

I think this La Niña is a tomboy. She's acting more like an El Niño.

Posted by: Yellowboy | January 25, 2011 3:36 PM | Report abuse

I demand light, fluffy snow!

CWG
Awesome reporting. You merit an award for your responsiveness and expert analysis.

Posted by: moo1 | January 25, 2011 3:37 PM | Report abuse

169 comments during an upcoming snow event and only 3 (boarderline 4) "I have some not very unimportant event (insert day) at (insert time). Should I cancel?!" Glad to see CWG readers are actually taking time to read the articles instead of demanding answers from a comment section. There is hope yet.

Posted by: TheMot | January 25, 2011 3:37 PM | Report abuse

I demand light, fluffy snow!

CWG
Awesome reporting. You merit an award for your responsiveness and expert analysis.

Posted by: moo1 | January 25, 2011 3:39 PM | Report abuse

@thepostischeap: And after WUSA booted Devon Lucie, he shows up a week ago on WJLA. (I can't remember if he was filling in on the weekend or if it was on their digital weather channel.) Thus continuing JLA's smart move of buying up frustrated/unappreciated talent in the area.

Posted by: petworthlad | January 25, 2011 3:40 PM | Report abuse

I demand light, fluffy snow!

CWG
Awesome reporting. You merit an award for your responsiveness and expert analysis.

Posted by: moo1 | January 25, 2011 3:40 PM | Report abuse

SNOWprise!

Posted by: jrodfoo | January 25, 2011 3:43 PM | Report abuse

School tomorrow looks to be a tough call for the counties. Any early thoughts CWG?

Posted by: Dylan0513 | January 25, 2011 3:43 PM | Report abuse

When will the next GFS run come out?

Posted by: SGS78 | January 25, 2011 3:44 PM | Report abuse

ounanm1, we don't have safe hotels. You run a 50/50 risk of getting brutally murdered just walking down the street minding your own business.

Just kidding. Pick any hotel in 20910 and it's not more than ten minutes by car or bus from WRAMC. I promise you won't get mugged or shot. You might have a homeless person ask you for a dollar. Look out.

Posted by: random-adam | January 25, 2011 3:46 PM | Report abuse

I think everyone( SNOW LOVERS) is just plain excited cause the words...BUST..DRY SLOT..OUT TO SEA...JUST MISSED US..hasnt been brought up today...

We finnaly may get what we have waitin on..

Posted by: BradFinWoodbridgeVA | January 25, 2011 3:46 PM | Report abuse

snowprise is the phrase I suggested earlier! I hope it sticks!

Posted by: homertuckumd | January 25, 2011 3:46 PM | Report abuse

@SGS78 I believe it comes out between 4:30-5:00.

Posted by: jms12 | January 25, 2011 3:47 PM | Report abuse

Should winter storm warnings go up tonight or tomorrow morning?

Posted by: cubscapsfan | January 25, 2011 3:48 PM | Report abuse

@SGS78

I think the GFS runs usually lag NAM by at least an hour or so.

Posted by: wappledoo | January 25, 2011 3:48 PM | Report abuse

My Boss is a big time snow hater...he has rubbed it in my face all winter..PLEASE...i hope i get to bust him up on this one!!!

Posted by: BradFinWoodbridgeVA | January 25, 2011 3:51 PM | Report abuse

@petworthlad & @thepostischeap

I for one don't like how all the mets are jumping around from station to station. Bob Ryan leaving ch. 4 was devastating. I don't care for Devon Lucie. I'm just glad that Bob is still on the air. The thing that bothered me was that his departure broke up Washington's best news team. I do, however, like how the former ch. 9 newscasters are on 7 now, Peterson, Bunyan and Hill, but they couldn't ever beat Vance, Gentzler, and Ryan.

Posted by: BobMiller2 | January 25, 2011 3:53 PM | Report abuse

I'm excited for this snow, and I'm a teacher working in southern MOCO. That being said I see no way the schools close tomorrow (although they may let out early) and if the event ends by midnight tomorrow this should be an easier clearing for the road crews than normal. My prediction is that unless you live in Frederick or Fauqier County you should do your homework. I like the half day we dont have to make it up.....indeed.....

Also I cant help but laugh at the guy who wants to see the Zone Two line move a few hundred feet so he can get more snow. Its as if one side of the street gets 6-12 and the other side gets 1-3 with rain. Perhaps he should get a place on the other side of the road if he wants optimal snow...I love it!

Posted by: inthemiddle2 | January 25, 2011 3:55 PM | Report abuse

@jms12 @wappledoo - thanks! Should be interesting to see how it looks in comparison. And just in time for the evening news. lol.

Posted by: SGS78 | January 25, 2011 3:58 PM | Report abuse

Someone waaay upthread asked about airports....I would suspect at the minimum that most aircraft scheduled to overnight will not come in and the associated first departures in the morning will not operate. A lot will depend on the airport itself and the individual carriers deice capability...DCA with one main runway might have more issues than IAD with multiple....IAD can clean one and still have another working at the same time. Late afternoon flts Weds may be iffy depending on accumulation, temps, and deice capability.

Posted by: Hiflyer | January 25, 2011 4:02 PM | Report abuse

new post up FYI.. incase anyone didn't know yet...

Posted by: jrodfoo | January 25, 2011 4:02 PM | Report abuse

SGS78

Your right..what if you live right on the line??? would your front yard get snow..and your back yard rain...

Im being silly..but seriously..I assume the LINE that they forecast has a pretty wide area to it i would think...maby a few miles wide i would guess???

Posted by: BradFinWoodbridgeVA | January 25, 2011 4:03 PM | Report abuse

NBC4 still emphasizing rain/snow mix, saying only some in the area will see accumulating snow. Whatever.

Posted by: visualglamour | January 25, 2011 4:05 PM | Report abuse

I for one don't like how all the mets are jumping around from station to station. Bob Ryan leaving ch. 4 was devastating. I don't care for Devon Lucie. I'm just glad that Bob is still on the air. The thing that bothered me was that his departure broke up Washington's best news team. I do, however, like how the former ch. 9 newscasters are on 7 now, Peterson, Bunyan and Hill, but they couldn't ever beat Vance, Gentzler, and Ryan.

Posted by: BobMiller2
***********************************

I agree Bob, if they ever lose Vance & Gentzler for any reason, I guess I'll jump ship to 7. I'm glad Ryan & Arch Campbell found new homes on ABC7.

Posted by: wadejg | January 25, 2011 4:11 PM | Report abuse

I feel like we rarely see this; I'm getting a 4-8 type forecast from the gang, 5-9 from the NWS, and 4-8 from TWC. Accu-weather is giving me 2-5. But all the local stations are calling for rain, still, and are saying MAYBE 1-3 inches. I feel like they're usually the one's screaming FIRE! FIRE!

Posted by: parksndc | January 25, 2011 4:14 PM | Report abuse

D.C. city streets are not at freezing, thus, initial snow is not expected to draw any accumulation on them. As we move into the nighttime hours and the temperatures drop, we will begin to see some street accumulation. However, because the storm is expected to end somewhere around 12, the majority of the accumulation will likely be on less traveled sidewalks and grassy areas.

City crews, who will be fully deployed, will have all night to treat what little does accumulate on the streets to enable a reasonably smooth commute Thursday morning.

If it is going to snow heavily, at night is the time for it.

Posted by: concernedaboutdc | January 25, 2011 4:16 PM | Report abuse

There are some comments which I think are misleading in regard to thunder snow. It's not just summertime type thunderstorms in winter, but rather something know as "slantwise" (not vertical) convection. I can't address this any further now, but I commented on this in my recent post on the Winter Weather Experiment

More later if still a question

Andrew Freedman will be posting soon an interview with Dr. Louis Uccellini done at the AMS meeting on the potential snowstorm and broader background material. Stay tuned

Posted by: SteveT-CapitalWeatherGang | January 25, 2011 4:20 PM | Report abuse

Ducked out of work early to do routine grocery shopping, before the non-CWG-reading public catches wind of the updated forecast and strips the stores bare! Nice to be ahead of the curve.

Also, ounanm1, I second random-adam's recommendations for hotels. The Marriott or the Crowne Plaza are particularly nice (as well as the Hilton, which isn't one of their fancier ones, so probably more affordable than you'd think), and they're located right on or near Georgia Ave.
GA Ave always gets cleared first in a snow event, and it's an easy zip down to Walter Reed.
I'd avoid the Comfort Inn and the Traveleodge, though, if safety is a concern over cost. Certainly not deadly, but possibly a bit outside the comfort zone if you're already nervous.

Posted by: JCR7 | January 25, 2011 4:23 PM | Report abuse

oh my gosh, no time to post, must go out and buy toilet paper, milk, and bread!!!

Posted by: woodbinemom | January 25, 2011 4:35 PM | Report abuse

Wow. People still raid the stores of water, milk and toilet paper before short lived storms? I'm in the wrong business. I generally have enough supplies to carry me a week on hand everyday.

Anyhow, I don't think stores will experience any delays on receiving deliveries on Wednesday or Thursday resulting in a shortage of supply.

But don't let me spoil others rituals and the stores sudden spike in profits.

Posted by: concernedaboutdc | January 25, 2011 4:37 PM | Report abuse

This winter has cheated me so many times, I'm not going to be getting my hopes up until I see the white stuff. And I did have to burn an annual day on that ice storm. . .but still -- come on sledding weather! We're itching to hit the hill!

Posted by: BadMommy1 | January 25, 2011 4:40 PM | Report abuse

I have lived in a snow climate for my entire forty-something years. Most MUCH worse than this one. But you wouldn't know it the way citizens here react to the whisper to snow. You would think we were in Birmingham, AL. Do you know that there in many parts of the country it is business as usual and there is no less than 6 inches of snow on the ground throughout the winter season. Life continues, as normal, to includes schools. They don't miss a beat for anything less than a prediction of 8 inches or more. Maybe this is why I can't get as excited, or bothered, as others.

Posted by: concernedaboutdc | January 25, 2011 4:44 PM | Report abuse

@concernedaboutdc

Cmon don't be a party pooper let us have our fun here. This is much deserved for snow lovers in this area who have been rather disappointed by this season's very meager snowfall so far. And also, a great thing about this area is that we are rather unadapted at handling bad weather, which means more school closings :)

Posted by: tombeek31 | January 25, 2011 5:38 PM | Report abuse

I've finished cursing and screaming now, so I can agree that the people who love snow have waited patiently through half our winter for a significant snow and deserve thier moment. Can't wait to leave my job at 6:00 PM tomorrow and flip a coin to decide if I want to chance being killed by a falling tree limb if I do the suburban route home or merely sit on I-495 for several hours while people who can't drive have panic attacks, and maybe get killed when a sliding semi-trailer rear-ends me. Then there will be the sheer joy or arising early to see if the executives will call a late arrival or snow day, whereupon I can commence shoveling wet heavy snow with one bad shoulder before trying to get to work, where all the stay at homes will call me for last year's insurance premiums while doing their taxes next to a cozy fire, while I worry if my pets have heat at home. Yippee. Excuse me, I feel another screaming fit coming on. Enjoy, my little snowfriends. It is your turn.

Posted by: GreybirdK1 | January 25, 2011 5:55 PM | Report abuse

After one brief run into the 40s after all this cold, are the roads going to be all that warm? You would think the ground would be still frozen solid.

Posted by: frontieradjust | January 25, 2011 6:31 PM | Report abuse

how can i go into my profile to update

Posted by: KENNETHMOTEN | January 27, 2011 10:25 AM | Report abuse

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