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Posted at 10:30 AM ET, 02/ 1/2010

Two storms to be possible snow producers

By Jason Samenow

Watching Tuesday night and weekend threats

*Cold, stormy start to February: Full Forecast through weekend *

Next Chance of Accumulating Snow: Tuesday night and the weekend
Probability of Accumulating Snow (1" or more): 45% and 35%

For snow lovers in the mid-Atlantic, this is your winter. After Saturday's half-a-foot, Reagan National now has totaled 2 feet of snow for the season, the most since 2003 and about 50% above average (for the whole season). Now, potentially sweetening the deal, we've got two more snow opportunities to track...

Snow chance #1 arrives late tomorrow afternoon and tomorrow night as a relatively weak area of low pressure developing off the Southeast coast heads northward. The track of this feature is quite uncertain and it may stay too far out to sea to produce accumulating snow. However, some of the latest models suggest it will track close enough to produce some accumulation over the region (particularly from I-95 and to the south and east). Also, the seasonal trend is for these southern storms to come a little further north and west than simulated in the models.

Temperatures won't be nearly as cold for this potential storm as the last one, so any snow that falls will not accumulate as quickly and it may even start briefly as rain Tuesday afternoon. Here's my assessment of snow potential:

Dusting or less: 25% chance
Dusting to 1": 30% chance
1-4": 30% chance
4"+: 15% chance

My most likely scenario for Storm #1: 1" or so of wet snow.
Confidence: Low

Storm chance #2 covers the period from late Friday through the weekend. This storm may be bigger than storm #1. However, there are large uncertainties with respect to its evolution and track.

Keep reading for more on Storm chance #2...

There is high confidence a storm will develop in the Gulf of Mexico midweek and then head northeastward. But as with all storms from the south, the exact track it takes will determine how much impact it has on the region. A more inland track would probably mean a little snow before a change over to rain (and/or mixed precipitation). A track too far to the south and east (i.e. a suppressed track) would result in little, if any, precipitation. A track just off the coast (in between the first two tracks mentioned) would probably result in significant snows.

The National Weather Service's Hydrometeorological Prediction Center is taking the potential for this storm seriously, writing in a discussion yesterday:

VERY HEAVY PRECIPITATION EVENT SEEMS LIKELY FOR THE MID ATLANTIC REGION SATURDAY VERY POSSIBLY INTO SUNDAY SPREADING NORTH AND NORTHEASTWARD. A SIGNIFICANT WINTER WEATHER THREAT IS POSSIBLE. HIGHER CONFIDENCE IN THE STRONG ONSHORE WIND CONSENSUS FOR A PROLONGED PERIOD OF TIME ALONG THE SOUTHEAST AND MID ATLANTIC SEABOARD WITH BEACH EROSION/COASTAL FLOODING FRIDAY INTO SUNDAY.

I don't disagree that there is high potential for a significant precipitation event somewhere in the mid-Atlantic region this coming weekend but I should stress it is very unclear whether this precipitation event will manifest itself as a significant snowstorm for the metro region. As I've mentioned before, in my experience many snowstorms simulated 5+ days out by computer models for the D.C. area do not materialize.

Keeping that in mind (as well the relatively high level of model agreement that there will be a storm), here's my assessment of snow potential for the weekend:

65%: Less than 1"
20%: 1-4"
15%: 4"+

My most likely scenario for storm chance #2: Too early to assess but I do tend to think the suppressed scenario is less likely than the other two I described which would mean some significant precipitation for the region. My other hunch is that cold air may be in shorter supply (relative to previous storms) meaning rain and/or sleet may enter the picture.

By Jason Samenow  | February 1, 2010; 10:30 AM ET
Categories:  Snow Lover's Crystal Ball, Snowmageddon  
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Next: Georgetown Snow

Comments

Come on Snowmaggedon part II! I would love a mid week dusting followed by a weekend storm.

Posted by: Bainbridge | February 1, 2010 5:48 AM | Report abuse

Bring it on!!!!

Even though snow Tuesday into Wednesday and over the weekend will wreak havoc with my upcoming busy schedule, I'll take it!!

We have been so snow starved the past few winters, this has been extra fun.

Posted by: Snowlover2 | February 1, 2010 7:07 AM | Report abuse

Latest model guidance keeps both storms a bit weaker and a bit more south and east. I have a feeling that 1" or less for the first storm is a good bet. For the second storm, it is just too early yet....

Posted by: snowlover | February 1, 2010 7:32 AM | Report abuse

I'm really hoping for another big one this weekend. Something that rivals 2003, perhaps? ;-)

Posted by: bachaney | February 1, 2010 7:50 AM | Report abuse

CWG, is that last paragraph referring to storm #2?

bachaney,
i'd be quite happy with something that merely rivals the dec 19th event...

Posted by: walter-in-fallschurch | February 1, 2010 8:06 AM | Report abuse

Obviously you all don't have to shovel it, drive in it or walk dogs in it. We ahve ahd enough snow for the winter out here in Clifton 36+ inches and don't need any more.

Posted by: omarthetentmaker | February 1, 2010 8:08 AM | Report abuse

@walter--

Yes-- That should've said storm chance #2

Posted by: Jason-CapitalWeatherGang | February 1, 2010 8:20 AM | Report abuse

On the contrary, Omar. I do all of the above in it and also, I go and play in it. Don't worry, be happy.

Posted by: manassasmissy | February 1, 2010 8:30 AM | Report abuse

Omarthetentmaker you are correct. The rest of us have hired men who shovel our walks and drive our cars for us.

Lets have a 2-3 incher mid-week and another two feet over the weekend!

Posted by: MKadyman | February 1, 2010 8:30 AM | Report abuse

walter--don't get me wrong, I would be happy with another Dec 19 sized event. But I'm dreaming...so why not dream big ;-)

Omarthetentmaker-I do walk, shovel, and (eventually, after it's stopped falling) drive in snow. Oh, and I live on a street that is NEVER plowed (it's too narrow and paved with brick) but I just love the peace snow brings to our otherwise frantic lives. So let it snow!

Posted by: bachaney | February 1, 2010 8:49 AM | Report abuse

I have to work this weekend but I am still hoping for a big snowstorm.

Winters like this are few and far between around here, so I am definitely enjoying it.

Posted by: JW211 | February 1, 2010 10:16 AM | Report abuse

Folks - I will be commuting from Rockville to Baltimore over the next 4-days, starting tomorrow. I should be leaving Bmore at 3pm tomorrow...any worries for me getting back into Rockville before the system comes through?

Posted by: authorofpoetry | February 1, 2010 10:51 AM | Report abuse

Personally, I hate snow. Can we move the Federal government to the Florida Keys? I'd rather take my chances with the hurricanes.

Posted by: greggwiggins | February 1, 2010 10:54 AM | Report abuse

Can we, pretty please, have this major, of behomoth, epic proportions storm take place on a Sunday evening so that the government can close for the rest of the week if not two.

Posted by: Hanz1 | February 1, 2010 11:00 AM | Report abuse

Greggwiggins -

As a former resident of New Orleans - I beg to differ.

Posted by: nolagirl67 | February 1, 2010 11:00 AM | Report abuse

@authorofpoetry

I think the earliest you'd see significant precipitation (assuming we get any) along that route would be around 4 p.m. (could end up being later). So, you may want to have a plan to leave just a little bit early depending on how the forecast and radar looks midday tomorrow. But for the most part your timing will probably work out ok.

Posted by: Dan-CapitalWeatherGang | February 1, 2010 11:01 AM | Report abuse

Author, you may see some flurries begin at the end of your journey but you're likely to get back in plenty of time. I'm still not convinced we'll see much accumulation out of this one, maybe a quick inch or so if we get banding overhead again. I think the weekend storm is again the one to watch.

Posted by: Brian-CapitalWeatherGang | February 1, 2010 11:02 AM | Report abuse

Dan and Brian - Thanks for the quick and helpful responses...this will help in terms of planning for me!

Posted by: authorofpoetry | February 1, 2010 11:05 AM | Report abuse

A comment re. yesterday's article on the Saturday storm in the Post. It said that the average amount of snow for the year is 8 inches which is incorrect. All of the data that I can find suggests an average of 16.6 for National and in the low 20 inch range for the surrounding areas. CWG may want to correct the Post reporters next time, especially since Dan was quoted in the article.

Posted by: JM222 | February 1, 2010 11:33 AM | Report abuse

Early model runs had this weekend storm lasting up to three days and giving us 36 to 48 [in places] inches of snow--bigger than both the Knickerbocker and the Washington/Jefferson storms.

Such an event seems a bit hard to believe--it will probably "bust" as the 1993 Superstorm did, and give us a bunch of wintry mix at times if the potential precipitation is really that high.

Posted by: Bombo47jea | February 1, 2010 12:04 PM | Report abuse

@JM222

The stat they were trying to communicate (but didn't quite do it) was that 8 inches is the average amount for the winter to date, not the whole season.

Posted by: Dan-CapitalWeatherGang | February 1, 2010 12:11 PM | Report abuse

My understanding is 1993 was a Miller type A (no secondary, just a primary hurtling up the coast). According to NWS Blacksburg, this weekend will be Miller type B with cold air damming and a secondary off of NC.

The main difference for us is the type B gets blocked from moving north. The blocking has to be just right to get a big dump of snow (not blocked too far south), but it could last for days in an extreme case.

Posted by: eric654 | February 1, 2010 12:30 PM | Report abuse

Noooooo!!!!!

Posted by: brandip_77 | February 1, 2010 12:44 PM | Report abuse

Low center passing too far south for significant accumulation here? A dusting to 1 inch? Then 1-2 inches. Then 3-5. then 4-6. Then......

Gee...where have we heard THAT one before? I wonder if any of the forecasters have learned ANY lessons from any of the snowstorms this winter.....ALL of them have substantially exceeded initial forecasts. And, in all of the storms, the TV forecasters (not the CWG) called an end to the precipitation shield WAY too early...by 5-7 hours.

I don't want to keep harping on this, like I did on previous threads, but my point is.....let's not make the same mistake now 4 times in a row.

Posted by: MMCarhelp | February 1, 2010 12:57 PM | Report abuse

Latest GFS has the weekend storm missing DC entirely to the south and east.....The waffle dance is on!

Posted by: snowlover | February 1, 2010 1:00 PM | Report abuse

Every single storm so far has trended north at the last minute. In order us to see something, this far out it seems to be good to be more north of the storm then directly in it's sights.

Posted by: kallieh | February 1, 2010 1:05 PM | Report abuse

The week of Super Bowl XXI (which took place Jan. 25, 1987), at least in Richmond, we had a midweek snow that closed VCU for two or three days (through Friday, I remember that). We went to see the Caps for the first time at Capital Centre (and also stopped at Potomac Mills for the first time on the way up) and only one lane of I-95 was completely clear of snow as we drove through Spotsy and Stafford. BIG piles of snow in the lot at Potomac Mills too. Driving back after the Caps game, they were already calling for the start of Storm #2, and by the time the game kicked off Sunday afternoon, it was snowing again in Richmond. Got enough to cancel classes for two MORE days. So maybe Super Bowl week is gonna be snowy again...

Posted by: ValleyCaps | February 1, 2010 1:08 PM | Report abuse

eric654, where is the srong cold-air damming this weekend for a strong Miller Type B storm going to come from? Temps look to be forecast a litle too high for that (upper 30's in the daytime), and there won't be the strong Arctic air mass entrenched over the region we had Saturday, with temps in the upper teens. You usually need bitter cold air and a lot of moisture aloft for really high snow totals.....the heavy, wet snow with temps in the 30s (typical for this area) usually doesn't accumulate rapidly into high totals.

Posted by: MMCarhelp | February 1, 2010 1:08 PM | Report abuse

About this coming weekend: If we don't get the snow, will it be snowing further north? We're planning on driving to NYC on Fri eve or Sat. morning. If it's raining/sleeting here, will it be snowier as we go north, or will the snow fall uselessly out at sea? (I mean some kid should get to go sledding somewhere....).

And if it's snowing here, will there be more or less snow along I-95 up to NYC?

Any crystal ball insights much appreciated...

Thanks

Posted by: reedd1 | February 1, 2010 1:26 PM | Report abuse

Remember watching Super Bowl XXXIV in January 2000 during a pretty decent snow storm. I lived out in the Shenandoah Valley then, so I'm not sure how much it snowed in this area.

Posted by: JW211 | February 1, 2010 1:40 PM | Report abuse

It's interesting to see the GFS taking the weekend storm out to sea now. The ECMWF has the low closer to the coast on the lastest run & not taking the storm out to sea. The main difference is the ECMWF is pumping the ridge on the west coast with stronger storm system entering their, allowing the low to come up the east coast and bring us a snowstorm. The question is which model is correct...?

Posted by: pseaby | February 1, 2010 2:06 PM | Report abuse

@reedd1

This one (the possible late-week storm) may have more potential to ride up the coast and hit the Northeast Corridor than the one this past weekend. But too early to say anything concrete about that.

Posted by: Dan-CapitalWeatherGang | February 1, 2010 2:17 PM | Report abuse

All I know is that I'm scheduled to be on a plane to Orlando at 6:20 PM on Friday. As long as that flight gets out, whatever happens here is just fine with me. Getting back ... can wait. ;)

Posted by: joshnva | February 1, 2010 2:53 PM | Report abuse

valleycaps,
that 1 - 2 punch in 1987 is burned into my memory: the first storm forced cancellation of our wedding for the Friday and the second storm pushed it off until the following Tuesday. Family from out of town unable to attend. Drifts were up to the roof gutters in Silver Spring. Total for both storms was well over 30 inches, I believe.

Posted by: wa2ono61 | February 1, 2010 3:11 PM | Report abuse

Check out the ominous 2nd/final paragraph of this latest update from the Hydrometeorological Prediction Center concerning this weekend's storm:

http://www.hpc.ncep.noaa.gov/discussions/pmdepd.html

Posted by: VAStateOfMind | February 1, 2010 3:21 PM | Report abuse

Latest NAM gives the area 2-4" of snow for the Tuesday/Tuesday night event.

Posted by: snowlover | February 1, 2010 3:28 PM | Report abuse

That's right, JW211, Super Bowl XXXIV was also played during a snowstorm in our region. I was driving home from the Caps' traditional Super Sunday afternoon match and still lived in Harrisonburg at the time, so I figured I might miss the first quarter of the game. Got home and it was already the second half...

Posted by: ValleyCaps | February 1, 2010 3:32 PM | Report abuse

Thats a long drive in treacherous weather ValleyCaps, glad you got home safely.

I was born in Harrisonburg, and lived in Mt. Jackson during thist time.

Posted by: JW211 | February 1, 2010 3:53 PM | Report abuse

@VAStateOfMind - all I can say is, NICE............

Posted by: snowlover | February 1, 2010 3:58 PM | Report abuse

it's a little early for the weather service to be getting excited right? I mean accuweather isn't even hyping yet. But let's hope they're right!

Posted by: bachaney | February 1, 2010 4:10 PM | Report abuse

Looking at the 7:30pm Infrared Satellite, impressed by the moisture feed coming out of the Gulf...things starting to look interesting.

Posted by: kdvols1 | February 1, 2010 8:00 PM | Report abuse

It's really fun to see this community spring up. Kind of reminds me of the early days on WeatherUnderground, with Jeff Master's hurricane blogs. Please keep up the good work and may the southern storm get it together and quiet our busy lives for a few days.

Posted by: drc231 | February 1, 2010 8:44 PM | Report abuse

LOL it was Snowmageddon!

Posted by: samdman95 | February 8, 2010 10:38 AM | Report abuse

The comments to this entry are closed.

 
 
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