Network News

X My Profile
View More Activity
The new Washington
Post Weather website
Jump to CWG's
Latest Full Forecast
Outside now? Radar, temps
and more: Weather Wall
Follow us on Twitter (@capitalweather) and become a fan on Facebook
Posted at 1:45 PM ET, 01/28/2011

What made Wednesday's storm special?

By Wes Junker

And a look ahead to next week's storm

It's to state the obvious that the severe impact of Wednesday's "Commutageddon" (leading vote getter so far) had mostly to do with the timing of the heavy precipitation, devastatingly coinciding with rush hour. But the physics of the storm itself were remarkable and gave rise to the impacts. Let's take a look at the combination of factors which made the storm so bad, and then I'll provide my early thoughts on next week's potential storm.

Intense upper level system generated freak thunder and heavy precipitation rates

This upper level system was unusually strong and brought to bear two different kinds of atmospheric instabilities that enhanced the upward motion within the storm contributing to the very intense precipitation rates. And the track of the system just to our southeast put the region in the sweet spot where these instabilities converged.

My discussion on Tuesday noted that there was an unstable layer in the upper levels of the atmosphere. This unstable layer resulted from cold air wrapping into the rotating storm at high levels increasing the vertical temperature gradient (how quickly the temperature changes with height in the atmosphere). The vertical temperature gradient promoted upward acceleration of the air similar to what you see with a helium balloon.

This type of instability is the same mechanism that produces convection and thunderstorms in summer. It leads to strong upward motion and intense rainfall within the thunderstorm. The initial band of heavy precipitation that moved through during the changeover from rain and sleet to snow was a result of this type of instability.

In addition, there also was another type of instability that also produced more isolated convection and high snowfall rates. It typically occurs when you have the horizontal temperature distribution (distance between two geographic locations) change rapidly as the temperature gradient in the vertical (from ground to cloud) becomes more packed with time. This is often referred to as slantwise convection.

slantwise.jpg
Temperatures and wind at 5,000 feet (850 mb) at 1 and 4 p.m. Wednesday.

The image above shows the temperatures and wind at 5,000 feet (850 mb) at 1 and 4 p.m. Wednesday. Note how the temperatures (the blue and green shading and lines) are packed together over Washington right at the time of the onset of heavy rainfall and sleet (at 4 p.m.). Also note that both maps show a warm 40 knot or stronger wind from the east (depicted by the barb symbols) blowing across this tight temperature gradient while, at the same time, temperatures are falling rapidly, evident from the advancement of the blue shades between 1 and 4 p.m.

These circumstances lead to incredibly strong upward motion and the slantwise convection. This phenomenon is often associated with intense banding of precipitation, high snowfall rates and isolated convection. (This complex subject has been the subject of academicf thesis papers. If you compare the conceptual model shown in this paper, you'll notice many similarities between it and Wednesday's storm.)

The bottom line is that the very strong dynamics, vertical motion and origins of the storm and two kinds of instability combined to help produce the intense snowfall rates.

The roads were cold, and sleet primed them for iciness

There were a couple of factors that contributed to the road problems. Despite the warm temperatures on Tuesday, we had just come through a period of several intensely cold days with daytime temperature below freezing and nighttime temperatures flirting with single digits. Therefore, the ground temperatures were quite cold allowing for snow to start accumulating quickly once the changeover occurred.

Many of us also experienced a period of heavy sleet. Large ice pellets, because of their density, do not melt quickly and the coating of sleet on the roads undoubtedly started greasing the skids for the accumulating snow that occurred later. Then the thump of heavy wet snow commenced. Wet snow offers less traction than dry snow as the thin coating of water on the flakes acts as a lubricant making it very slick. Wet snow also is heavier than dry snow and is harder for the car to push out of the way. Because it is so much heavier than drier snow, heavy accumulations of wet snow can lead to hydroplaning. The heavy wet snow coming right at the height of rush hour led to multiple fender benders and lots of abandoned cars as the traction and visibility were both badly impaired. Heavy wet snow right at rush hour is a terrible combination that always causes commuter nightmares.

The snow was unusually heavy

Hundreds of thousands of area residents lost power and extensive tree damage occurred - all of it due to the weight of the snow. Temperatures were about as warm as they could be for snow to fall. Usually, the warmer it is when it snows, the higher the water content and hence the weightier the snow is.

Across much of the region especially from the city east, surface temperatures were at or a little above freezing for the duration of the storm. For example, the surface temperature at Reagan National Airport never fell below freezing. The warm surface temperatures allowed the very lowest part of the cloud to have miniscule water droplets that adhered to the snow making it wet and gloppy. Therefore, the snow to liquid ratios even during the height of the storm in many places were significantly below average making the snow that much heavier.

Even regions to the north and west of the city that had their surface temperatures fall below freezing had heavy, wet snow and low snow to liquid ratios. The temperatures through a fairly deep layer of the atmosphere were above -4 C, resulting in a lot of supercooled liquid water within the cloud which produced riming. Snowflakes that are heavily rimed typically produce snow to liquid ratios in the 5-1 (i.e. five inches of snow per inch of rain) to 9-1 range.

By contrast, fluffier, lighter snow is comprised primarily of stellar dendrites which form at around -15 C. This kind of snow often has a snow to liquid ratios of 20-1 provided the surface temperatures are below freezing.

What about next week's storm?

A cold surface high pressure system is expected to shift across the Great Lakes to our north and then out to sea prior to the development of another potential storm for sometime around the middle of next week. Right now, it looks the storm will primarily track toward the Ohio Valley before reforming along the Atlantic coast with all the uncertainty that such storms produce for our area.

This kind of set up usually leads to precipitation type forecasting challenges and, this far in the future, speculation about either the dominant precipitation type or amount is meaningless. All we can say is there is potential for snow, ice and/or rain in the Tuesday through Thursday timeframe.

Dan and Jason will post an update Saturday and I'm planning on writing a technical discussion about the storm on Sunday. Hopefully, by then, the storm's evolution will be clearer.

(CWG's Jason Samenow contributed to this article)

By Wes Junker  | January 28, 2011; 1:45 PM ET
Categories:  Latest, Recaps, Science  
Save & Share:  Send E-mail   Facebook   Twitter   Digg   Yahoo Buzz   Del.icio.us   StumbleUpon   Technorati   Google Buzz   Previous: What should we name Wednesday's storm?
Next: PM Update: Cold tonight, few flurries Saturday

Comments

This was REALLY an impressive storm. I sympathize with those poor commuters who were stuck on the GW Parkway for 13 hrs. I don't know how you survived it! Hopefully that won't happen with this next storm.

I'll be looking forward to the update tomorrow and then the next one on Sunday.

Posted by: BobMiller2 | January 28, 2011 1:59 PM | Report abuse

Snow crystals and stellar dendrites and riming oh my! By linking to those amazing pictures, you just created a snow-geek for life.

Posted by: casa_wasabi | January 28, 2011 2:10 PM | Report abuse

Normally to this type of writing I would say "whatyoutalkingboutwillis?" but you did such an incredible job that amazingly I understood it all! Extrem kudos for breaking it down so that it could be easily understood!

What contributed to the amazing transition from sleet to snow? I mean, it looked like one of those special effects on tv where you're lookiong at something and then it transforms into something totally different in the twinkling of an eye (like when they show a young girl morped into an elderly lady in the blink of any eye).

Posted by: luvhh1 | January 28, 2011 2:20 PM | Report abuse

What causes a "capped column" as shown in the link to the snowflake pictures? That's an odd one.

Posted by: AsymptoticUnlimited | January 28, 2011 2:20 PM | Report abuse

Thanks Wes for all your work pronosticating this thunderous tree gobbling beast.

Posted by: FIREDRAGON47 | January 28, 2011 2:23 PM | Report abuse

I think the lesson learned is this. You dont have to wait for OPM to say it's time to go home...Read CWG and follow the lead of the pro's.

Posted by: SA-Town | January 28, 2011 2:25 PM | Report abuse

AsymptoticUnlimited, others,

more on snowflakes:

http://www.its.caltech.edu/~atomic/snowcrystals/class/class.htm

and, see the cool "morphology diagram" here:

http://www.its.caltech.edu/~atomic/snowcrystals/primer/primer.htm

Posted by: walter-in-fallschurch | January 28, 2011 2:26 PM | Report abuse

luvhh1, when you get sleet the warm layer temperature was probably only a 1.5 degree celsius and the entire column was cooling due to the very strong upward motion and the dynamics of the storm A shallow warm layer with the temp at 0.5 degrees C will generally produce snow so it only took a little cooling to gt the rapid changeover.

AsymptoticUnlimited. snowflake type is determined by temperature at which the cloud forms and the amount of supersaturation that is present with respect to ice. The table below gives a rough idea of the conditions that are present when different types of flakes form. http://www.its.caltech.edu/~atomic/snowcrystals/primer/morphologydiagram.jpg
on the same site a simple guide to snowflakes is available.http://www.its.caltech.edu/~atomic/snowcrystals/class/class.htm
it's all fascinating stuff.

Posted by: wjunker | January 28, 2011 2:36 PM | Report abuse

I think that the events during the evening rush during the Thunderplop will change the way that DC-area folks look at OPM. Personally, I just subtract one hour from when they close early and roll. Most folks will be making their own calls moving forward. I left DC at 1pm. Home 35 miles west by 2pm. Even for the standard non-weather geek, the terms "intense" and "1-2 inches per hour during rush hour" were abundant by the time they logged on in the morning. Lesson learned - You are the boss of You.

Posted by: DullesARC | January 28, 2011 2:40 PM | Report abuse

Thanks, Walter and Wes. Much appreciated.

Posted by: AsymptoticUnlimited | January 28, 2011 2:41 PM | Report abuse

A classic DC storm. Begins as rain, changes to ice, and then all snow. Unpredictability in the forecast creates paralysis about closing. Transplants from other regions foul the roads in a way unlike any other city.

Posted by: blasmaic | January 28, 2011 2:47 PM | Report abuse

You've left out the biggest single impact on the commuter chaos: people don't know how to drive.

I have never had any problem getting through snow...certainly had no troubles during the height of Wednesday's storm.

While a good AWD/4WD system helps (I drive a Subaru), it really all boils down to technique.

The single most important thing DC-area snow drivers need to learn: if you're stuck, more gas will make it WORSE, not better.

Posted by: scott_bradford | January 28, 2011 2:49 PM | Report abuse

DullesARC, very good points, and your formula as applied to OPM's recommendations is a good common-sense rule of thumb.

As a federal worker myself, I've been known to ding OPM for their decisions from time to time but don't feel their two-hour closing on Wednesday was a bad decision. I'm actually shocked they A) made the decision by late morning, and B) decided to close the feds down early AT ALL, but I think two hours was sufficient for most folks to get on the road home, based on weather guidance at that time.

I think the biggest problem Wednesday evening is that SO many federal workers looked out the window at work and didn't SEE anything falling from the sky until 3:30 or 4 p.m. and figured they still had plenty of time to get on the road. (Some of those folks were likely suffering from "cry wolf" syndrome, too, brought on by a few local and internet-based meteorologists - NOT the CWG.)

Couple that with a LOT of private sector companies in and around the Beltway that simply ignore what the feds say, and insist that their employees stay until quitting time regardless of what the weather is outside (verified by many of my friends working for said companies), and well...you had the perfect storm - pardon the extremely bad pun - for the commute from hell.

Posted by: ToBeBlunt | January 28, 2011 3:05 PM | Report abuse

Most larger metropolitan areas that get large snow storms tend to have significantly more snow removal equipment (and larger budgets for it). Id guess that our population to snowfall to snow removal resources is quite low compared to the national average when you take all three of those factors into the equation. NYC gets double our (DCA) snow, has double the people, but likely more than double the budget...we are obviously susceptible to a foot of snow at any time here. Our lack of resources, major road arteries and insistance on being told what to do rather than doing it ourselves will continue to create 10 hour commutes the next time it snows at 4pm heavily on a weekday. Driving skill - eh, not so much of an issue during a rush hour event. Pure overload was more of an issue.

Posted by: DullesARC | January 28, 2011 3:08 PM | Report abuse

Is there any simple formula for understanding the ground's ability to stay at a temperature - it's temperature inertia? Obviously, grass has less inertia than concrete.

With temperatures in the teens for quite a number of hours in NW DC and with all the shade and exposed high mass objects like sidewalks, granite buildings, even cars, it really seemed like although the air was warm the day before the snow, the ground never caught up to those ambient temperatures.

Posted by: easyenough | January 28, 2011 3:08 PM | Report abuse

Thanks Wes! Enjoyed both the pre & post analysis.

Posted by: parksndc | January 28, 2011 3:12 PM | Report abuse

Thanks, as always, for the detailed article. Out on a mountain road w/ above the ground power in Warren County, I feel fortunate to have not lost power. I think our snow must've been at least somewhat drier... at least it didn't feel especially heavy when shoveling around the mailbox yesterday. For some of the storm, it looked like we were actually in the clouds here at 1900 ft.

Posted by: spgass1 | January 28, 2011 3:14 PM | Report abuse

Another good recommendation, which I believe @BobMiller2 made this morning - it helps a LOT to take at least a few minutes to review the CWG site throughout the day of a weather event, if only to get a handle (by way of helpful comments from everyone here) on what the weather might be doing in your neighborhood. I feel real-time reporting of weather conditions via commenting can be a tremendous help.

CWG, I know you guys are on Twitter - are you routinely choosing a Twitter hashtag dedicated to a storm event? We have found at work that isolating "conversations" or ongoing reporting using dedicated hashtags are a godsend on Twitter, for many different types of events. (I think you *are* doing this, just haven't looked you up on Twitter lately...)

Posted by: ToBeBlunt | January 28, 2011 3:16 PM | Report abuse

I have to think that ground temperature manipulation is going to have a real future in the tech sector...they put coils under billion dollar stadiums to keep them warm enough to melt snow - as we replace our infrastructure/roads, I bet this gets some traction (pun intended) over the next 20 years or so. The cost of maintaining our roads with salt, sand, shovels, manpower...it has to be cheaper if we can do it "remotely" via the flick of a switch. Of course, Walter is in it for the opposite effect! Sorry to hijack the technical wx post Wes!

This was about the 5th time Ive witnessed a Thundersnow here, but this seems to be the most widespread event of this nature that I can remember in 20 years. What does La Nina have for us next? If it werent for a few very near misses, this would be right there for inclusion in snowiest DEC-JAN in DC. With the cold hanging tough for 8 weeks now, this winter has not been a bust by any definition.

Posted by: DullesARC | January 28, 2011 3:17 PM | Report abuse

Wes,

Great forecasting job and excellent write up for a very interesting weather event!

When it was 3 PM and nothing was happening, I got pretty nervous. It seems like the storm came a couple hours late and left a couple hours late.

Wes, it's hard to get very bullish about the upcoming Tuesday event. Low 500 mb heights in NE Canada are normally the kiss of death. Of course, every other rule this winter has been broken, so why not that one?

Posted by: frontieradjust | January 28, 2011 3:21 PM | Report abuse

losing power definitely changes the whole "feeling" of the snowstorm experience. just adapt - after all, what else can you do?! it can be a pain. i feel for all those whose power is still out. but also, one should be ready for that to happen. it's not like no one saw this storm coming.

anyway... i just saw video of that bank robber in MoCo. he was taking the hostage, backing away from police and he... SLIPPED ON THE ICE!!! so...wednesday's snow prevented a robbery and possibly saved the life of the hostage... hahaha!

so, snow-dislikers can't say nothing good ever comes of it...

Posted by: walter-in-fallschurch | January 28, 2011 3:28 PM | Report abuse

I agree with scott_bradford on this one. I drive a rear wheel drive sport sedan with all season tires. Despite the 3 hours it took me Wednesday afternoon to complete a normal 35 minute trip, I had minimal trouble with the weather. The problem was all the people who had no practical knowledge of the basic principles of driving in snow/sleet/slush that caused problems.

As for OPM, I've long thought they need to switch to a zone system on these things, sort of like boarding an airliner with higher rows boarding first. Zone 1 would be inside the beltway, Zone 2 would be the close in counties (PG, MoCo, FFX and ArCo), and Zone 3 is beyond that. Then release Zone 3 folks first (that would include folks who work in zone 3 and live in DC), an hour later release Zone 2, and then Zone 1 an hour later. This would allow those with the furthest to go to get out of the way of those closer in.

Just my 2 cents...well, given the length, more of a quarter I suppose!

Posted by: ftwash | January 28, 2011 3:31 PM | Report abuse

This latest rush hour fiasco was reminiscent of the horrible rush hour the night before the JFK Inauguration in 1961. That time it was very heavy snow combined with a sudden temperature drop from upper 30's to low 20's. Everything froze instantly to a glaze of ice which was rapidly covered by falling snow.

Also, there was a wild thundersnow event in March 1984 with continuous lightning and thunder accompanied by 40 mph winds. There were 4" in 45 minutes in College Park, generally 2 to 6 inches thoughout the Metro area. It came at rush hour and was another traffic disaster.

Posted by: frontieradjust | January 28, 2011 3:34 PM | Report abuse

@ frontieradjust - "Of course, every other rule this winter has been broken, so why not that one?"

EXACTLY. This winter will go into the La Nina database with an asterik....but so did 1996.

Posted by: DullesARC | January 28, 2011 3:36 PM | Report abuse

Sure do like the Airline Zone Release plan. But it makes way too much sense to ever get done...

Posted by: DullesARC | January 28, 2011 3:39 PM | Report abuse

Andy thanks. The only bad thing about the storm was losing power for 36 hrs so I didn't get to take part in the fun on this site during and just after the event.

Posted by: wjunker | January 28, 2011 3:47 PM | Report abuse

I'd like to put in a good word for OPM. For the first time I can remember, they said "feds SHOULD leave two hours early." Not may leave, no stuff about liberal leave. Just "should leave". Between that change in tone and the CWG, I left and had a normal commute and watched the rain change to sleet to snow within ten minutes from my windows at home.

Posted by: busgirl1 | January 28, 2011 3:58 PM | Report abuse

Wes/Jason: Superb description of weather elements accounting for the mush of mixed precipitation types that brought chaos to the area roads and highways. One item you didn't mention was the abundant supply of moisture available to developing system.

It's especially rare to feel the effects of both vertical and slantwise convection so close in time and space. It can occur only when you are under the sweet spot of the initial phase of a rapidly intensifying low-pressure center tied to an unusually short-wave length system aloft.

As you but readers do not know is that I was dubious that the models could pull this off. But, they did - not perfectly - but good enough to consistently provide guidance for successfully tailoring and refining your forecasts to the degree made possible by your uniquely remarkable insights and professional experience.

Posted by: SteveT-CapitalWeatherGang | January 28, 2011 4:03 PM | Report abuse

Question

I believe OPM in the past has used AccuWeather as their provider of weather information upon which closings, early dismissals, etc are based. Still True??

Posted by: SteveT-CapitalWeatherGang | January 28, 2011 4:08 PM | Report abuse

SteveT-CapitalWeatherGang, good point about the moisture, I actually had that and the origins of the storm in an early or at least in my thoughts prior to writing the piece but somehow either lost it or edited it out for some reason. Coming up fro the south pretty much assured that we'd get an inch or so of liquid equivalent. It was fun storm to forecast as the models were pretty consistent with their forecasts inside of 48hrs except for the occasional latent heat induced glitch that kept trying to take a low away from shore on some of the runs.

Posted by: wjunker | January 28, 2011 4:14 PM | Report abuse

Wes, NCEP has confirmed that the latent heat problem you refer to (erroneous convection)is, indeed, spurious - modelers are assessing the nature and fix to the problem)

Posted by: SteveT-CapitalWeatherGang | January 28, 2011 5:02 PM | Report abuse

I doubt that OPM uses a commercial source for their weather information to make closure decisions. As a federal entity, they likely coordinate that information with the National Weather Service.

Posted by: two2 | January 28, 2011 5:04 PM | Report abuse

ToBeBlunt, I agree that too many waited to see the first flakes before leaving. I know several myself who did that even after I told them it would probably be too late. I think people are used to a much slower start to accumulation than we saw on Wednesday. Once you get into those kind of rates you're most likely going to get stuck if you're outside.

Posted by: Ian-CapitalWeatherGang | January 28, 2011 5:14 PM | Report abuse

Wes, I was glad to see you comment on the fact that Tuesday's warm temps had to be considered in light of the preceding several very cold days/nights. I'm no physicist, but I'm pretty sure that one warmer day wasn't enough to warm up the road surfaces substantially. That's why I never could understand the near-unanimous thinking by TV mets that "it was so warm on Tuesday that this will have trouble sticking"!

Posted by: petworthlad | January 28, 2011 5:26 PM | Report abuse

Unlike most if not all of our recent big DC snows -NAO didn't appear to be a contributing factor. Indeed, with the frontal convection dragging down into FL and Cuba and a PNA West Coast UPA ridge it looked like an El Nino system. What gives with our supposedly currently strong La Nina, which acted like anything but a La Nina in this case? Sounds like a good CWG blog topic for whoever is your Nino/Nina blog expert!

Posted by: buzzburek | January 28, 2011 6:02 PM | Report abuse

buzz

The La Nina has been strong in the sense of it's explicit definition, i.e., colder than normal sea surface temperatures in the tropical Pacific. However, the response in mid-latitudes has been atypical - in fact, more El Nino like, especially through mid January or so. I could, but will leave it to others if they wish to blog further on this subject.

Posted by: SteveT-CapitalWeatherGang | January 28, 2011 6:43 PM | Report abuse

As a Federal worker myself, I can tell you that some agencies did NOT inform their workforce of the OPM decision to release employees early in a timely manner. The only reason I knew about it before noon was because I signed up for 'Breaking News' emails from a local website. When I got the email, I immediately went to CWG to check the weather update. I saw Jason's post about not being on the roads after 4pm, and IMMEDIATELY called southbridgedad at work to inform him of same. We came up with our 'escape plan', and left in plenty of time to get home safely. Fortunately, southbridgedad had already received the info on the early release from his supervisory chain. The supervisor in my office was returning from a meeting and heard the news of early release on the radio in his car. He made sure we were all aware of the news, and insisted we leave as early as possible.

When I returned to work, I found the agency where I work informed employees of the 2 hour early release via email at 1:55pm. For those whose workday ended at 3pm, they were already behind.

OPM made the right move to release workers early, but sending out the release even ONE hour earlier could have made a huge difference. Also, workers need to take responsibility for themselves and keep themselves informed.

Also, a bookmark of CWG on everyone's web browser of choice should be a requirement. :)

Just my two cents.

Posted by: southbridgemom | January 28, 2011 8:33 PM | Report abuse

southbridgemom, I couldn't agree more; I thoroughly believe CWG saved many, many people from being stuck in traffic for 13 - 14 hrs. CWG knows what they're talking about and will always give you the full story.

Have a nice evening!

Posted by: BobMiller2 | January 28, 2011 8:41 PM | Report abuse

@bobmiller2-- Absolutely! That's why I go to CWG for the REAL story. Honest to goodness analysis, and no hype. AND, if they make a mistake they admit it. What a concept... ;o)

My 17 y/o daughter told her friends a storm was coming, and they laughed at her. One asked her, "how do YOU know?". She told them the CWG said so, and they are the best source for weather info. They believe her now!

Hope YOU have a great evening as well!

Posted by: southbridgemom | January 28, 2011 8:47 PM | Report abuse

Extremely beautiful and impressive storm. I have to say that I am one who loves storms. I sympathise with those who got stuck or stranded. However the company I worked for was right on time when the corporate office called in at 12 noon and gave the order to shut operations down at 2 so everybody could get home.

I heard so many horror stories of other businesses where managers would not close, when they did it was too late, and most people even made the bad decision to get on the road late driving directly through the storm. One lady said she just could not stand spending the night in her retail shop in Georgetown.

Posted by: tedleski | January 29, 2011 3:25 AM | Report abuse

That it occurred during rush hour and bad decisions by citizens.

Posted by: interactingdc | January 29, 2011 6:30 PM | Report abuse

Did anyone else see the sky lighting up or flashing brightly for what seemed like an hour, around 8pm? Live in Annandale, and I had never experienced anything like that before.

Posted by: KCD2Fit4u1 | January 29, 2011 10:00 PM | Report abuse

Did anyone else see the sky lighting up or flashing brightly for what seemed like an hour, around 8pm? Live in Annandale, and I had never experienced anything like that before.

Posted by: KCD2Fit4u1 | January 29, 2011 10:08 PM | Report abuse

Thanks for the in-depth analysis, Wes, and the reference material to "re-learn" some of the finer points of snow forecasting. I think this storm was well forecast with respect to both timing and totals. The sad fact is that we do not, and will not ever, have the infrastructure or equipment to handle 2"+/hour snowfall rates at rush hour. The rain early in the day made pre-treating the roads impossible, and the quick changeover to snow of that intensity would have brought even Chicago or Boston to a grinding halt. We were all very spoiled last winter with most of the heavy snows falling on weekends. (15.0" on Saturday Dec 19th, 6.4" on Saturday January 30th, and 17.8" on February 5th-6th which was a Friday night/Saturday morning. Those 3 events represent about 75% of the snow that fell last winter. The 10.8" that fell on February 9-10th (which was a Tuesday-Wednesday) was a more typical high-end, high-impact event. To be fair to the OPM and every other employer, the only way to have prevented the problem would have been to either send everyone home at or before noon, or just have let people stay home in the first place. And I, as a meteorologist with 20+ years on camera, can tell you that I would have never gone so far out on a forecasting limb as to tell OPM to shut down 8 to 12 hours before the first flake. We have all been witness to that kind of meteorological madness in the past and it's why we wait... only to inevitably send people home at the height of the storm. Keep up the good work.

Posted by: ChuckBellonNBC4 | January 29, 2011 10:21 PM | Report abuse

The comments to this entry are closed.

 
 
RSS Feed
Subscribe to The Post

© 2012 The Washington Post Company