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Posted at 01:30 PM ET, 12/28/2012

Minor snow event likely for D.C. area Saturday morning, coating to a couple inches possible


Update, 1:30 p.m.: The National Weather Service has issued a winter weather advisory Saturday for northern Fauquier, Loudoun, Montgomery, and Howard counties and locations to the north and west for an expectation of 1 to 3 inches of snow. Fairfax and Prince George’s county, the District, and points south and east are not included in an advisory at this time.

Original post (from around 11 a.m.): Since the crippling Commutageddon storm of January 26, 2011 (almost two years ago), snow events in Washington, D.C. area have - without exception - been minor. They’ve produced 1-3 inches of snow at most and mixed with sleet and rain in many cases. Saturday morning brings yet another of these relatively inconsequential opportunities for light snowfall and/or mixed precipitation.

Snowfall begins Saturday morning around or just before dawn and ends by midday or early afternoon. Snow may mix with or alternate between sleet and rain, especially inside the beltway and south and east.

“Accumulating snow is likely in the far northern and western suburbs where 1 to 3 inches are expected,” says Capital Weather Gang’s winter weather expert, Wes Junker. “Inside the beltway it looks like the precipitation will begin as snow but may mix with or even change to sleet and rain as temperatures climb into the mid-to-upper 30s by afternoon.”

STORM TIMELINE

4 AM to 8 AM SATURDAY
Light snow and/or sleet develops SW to NE . Temps 29-33.

8 AM to 11 AM
Snow, except snow and/or sleet S & E. Temps 30-35.

11 AM to 2 PM
Light snow and/or sleet, possibly mixing with/changing to rain before ending S & E. Temps 32-37.

See below for impact forecasts and frequent questions....

IMPACT FORECASTS

FREQUENT QUESTIONS

When/where will the heaviest frozen precipitation fall? Early-to-mid morning will likely be when the steadiest precipitaton falls, it should be fairly uniform - light to moderate in intensity - throughout the region although we can’t rule out a locally heavy burst somewhere.

Will the frozen precipitation stick? Since overnight temperature should drop to near or below freezing and it’s been relatively cold lately, snow and/or sleet that falls early in the early morning should stick. However, as the morning wears on and the possibility for mixing increases especially along I-95 and to the south and east, accumulation prospects may diminish.

When will travel be most difficult? Probably in the 8-11 a.m. window, especially north and west of the beltway, but this will not be a crippling storm. Roads will be passable, especially those treated.

Where will the most hazardous travel occur? In the normally colder outer suburbs in northern Montgomery, Loudoun and Frederick counties, including locations like Damascus, Ashburn, Leesburg, and Frederick. Snow-covered, slick roads become likely Saturday morning, especially those which are untreated..

Will my flight be cancelled? Probably not. A few delays are likely in the morning due to snow or mixed precipitation, but it shouldn’t be a huge deal for airports.

When will conditions improve? Most likely between 11 a.m. and 2 p.m. as precipitation tapers off and temperatures rise safely above freezing throughout the region.

Could the storm bring less snow than expect? Yes, there is a chance precipitation type would be more sleet and rain with little accumulation, especially from I-95 and to the south and east. “If the surface temperatures end up warming as forecast by the models or more, then accumulation will be limited to minor accumulations on grass and car tops in the city,” says CWG’s Junker.

Could the storm bring more ice/snow expected? “If the surface temperatures end up being a little colder or warm a little slower than the models are currently projecting, then higher accumulations might be reached in the city,” says Junker. One to three inches inside the city is probably the most that could be expected.

Other forecasts:

National Weather Service Sterling

National Weather Service HPC

WJLA- ABC7

WRC- NBC4

Dave Tolleris (WxRisk)

By  |  01:30 PM ET, 12/28/2012

Categories:  Latest, Winter Storms

 
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