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Posted at 03:28 PM ET, 03/07/2013

Snowquester: The pictures tell its story best

Snowquester, for all its maddening quirks and unfulfilled promises, was quite the photogenic storm. Five different images tell the story of this big snow tease, and make an indelible impression on our collective minds. For some, the following images will best communicate the storm’s epic failure, but, to others, the majesty of these moments in time will override more depressing thoughts.

We start with the imagery from the NWS Radar Mosaic, as it appeared during the 2 o’clock hour of Wednesday morning.


Snowquester’s solid precipitation shield engulfs DC in the early morning hours.

By this time, moderate precipitation (most of it in the form of snow) had overspread the area. Warm advection ahead of the parent low pressure system moving across Ohio initially supported this batch of snow and some rain. It’s during this stage that the trained weather watcher would be thinking, “Look at that – finally, for one of the very few times this winter, a precipitation shield filled with mostly snow had decided to set up over D.C. And I know that when the low pressure reforms over North Carolina, that steady moisture feed streaming in off the Atlantic will keep feeding the snow machine.”

The bleary-eyed, caffeinated storm enthusiast would also be thinking highly of the convective line extending south off the Carolina coast. Storminess here has got to bode well for a dynamic setup with the new system, which will continue to tap the moisture laden air mass of the Atlantic. It was so worth it for the snow lover to stay up this late.

Now, NASA enters the picture, showing off its breathtakingly beautiful imagery from the GOES 13 satellite.


This is a nice shot of Snowquester and its textbook cold-core low features

The image, captured around 6 a.m. yesterday, shows Snowquester’s elegant, well-built structure – that resembling a classic cold-core low pressure system. In just this one snapshot, you can identify the comma head over the Mid-Atlantic, cold conveyor belt extending across the Northeast and warm conveyor belt running up along the Gulf Stream. This is too classic to be true; our D.C. snow fortunes have turned around! Never again will I set my sights on the Plains or Midwest for a crushing blizzard. We have got all the ingredients in place here, yes, right here, in the capital of the free world.

By late morning, the region has flipped back and forth between snow, a snow/sleet/rain mix and just plain rain. Temperatures have safely risen above freezing, and much of the accumulation has already occurred across the far western suburbs. Snow is easy to spot throughout the metro area, but the fat, wet flakes are sticking to only car tops, grass, trees and untreated sidewalks.

We’re not done yet! Look at that cluster of lightning strikes to the south over Virginia. Thunderstorms.


This image from the CWG Weather Wall shows a cluster of thunderstorms over central Virginia (see lightning symbols at bottom of image). Some in and around DC would experience thundersnow from the system just after noon.

Imagine if they pushed up here. The vaunted thundersnow might make things interesting. Higher snowfall rates will overcome the high sun angle of early March. That’ll paint the blacktop white. That will make me happy.

As it turns out, the thundersnow does advance into the area. Waldorf and the other closer-in southern/eastern suburbs witness the pulsating phenomenon, as does the city itself shortly after noon. Their palate cleansed, snow lovers are now eagerly looking forward to the rest of the afternoon. Snowquester will be overhead for another five-to-six hours. Wouldn’t it be a shame if those heavy rain bands over the Eastern Shore failed to pivot back across the Chesapeake? We’d be missing out on more opportunities for thundersnow and a major pasting.

If only the precipitation had stayed mostly snow. Having lost the cooling from early in the day, D.C. eventually transitioned to all rain during the afternoon. Visible satellite imagery taken in the 5 o’clock hour continues to show some banded structures over Maryland and Virginia, but, of course, except for the higher elevations to our west, these were rain-filled bands.


On the imagery, note the sharp western edge of the precipitation shield extending south from central New York and Pennsylvania into the Blue Ridge mountains of Virginia.

In the mountainous areas of Virginia where temperatures stayed at or below freezing through much of Wednesday morning, a thick snow cover shows up rather nicely on the imagery. Also note extension of this snow cover into the northwest part of North Carolina.

The last of our five images comes courtesy of the College of DuPage Weather Lab. It’s a long loop of the radar at Wakefield, Va., as the storm progressed throughout the day: Link to loop

See how, early in the loop, the circulation center of Snowquester passes directly over the radar location. This passage happened during the morning hours when many in D.C. still held high hopes for a significant snowfall. As the rain and embedded thunder dissipates and pulls away from the radar site, so, too, does our attention to the storm and belief in its “snowability.”

Yes, the storm left a big footprint on areas well to the west of the District, as the snow depth graphic below shows.


Post-storm snow depth analysis courtesy of NOAA’s National Operational Hydrologic Remote Sensing Center

Amounts of 15 inches or more were common along the I-81 corridor, with some stations reporting 20 inches. Northwest sections of Loudoun County posted nine inches, while areas along the western portion of I-66 saw anywhere from 7-12 inches. Closer to town, a general 1-3 inches accumulated before the afternoon rains washed nearly all of the snow away. And within the urban core, the snow could only be measured in fractional inches.

A day that had begun with so much promise instead succumbed to the snowless forces of recent years. Fortunately, we can still marvel at the beauty of this one storm in this otherwise unsightly winter.

* Meteorologist Rick Grow blogs about the weather for The Frederick News-Post . He has a degree in atmospheric sciences from UNC-Asheville and previously worked at MDA EarthSat as a forecaster.

By Rick Grow*  |  03:28 PM ET, 03/07/2013

Categories:  Latest, Local Climate, Recaps, Winter Storms

 
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