Sunday, February 25, 2007
Accumulating Snow Continues Across DC Area
Snow could briefly mix with ice and rain this afternoon
Team Forecast @ 1:15 PM
*Winter Storm Warning in effect until 4am MON*
Nowcast 1:15pm: Moderate snow, possibly mixing with sleet and a bit of rain, is expected to continue over the next several hours before tapering this evening. The highest accumulations are expected in the colder suburbs, while in D.C. amounts will likely be less due to surface temperatures at or slightly above freezing. Even downtown, though, snow has been reported to be sticking to roads, especially during heavy bursts of precipitation.
Summary: With snow continuing to fall across the metro area, accumulations in the District are already being reported on the high end of the 0.5-2" predicted here late last night. In the immediate northern and western suburbs, accumulations have already surpassed the 2-3" predicted here, with reports of 3-5" and rising. Further west, in the mountains of West Virginia, accumulations in some locations have reached 6" or more.
The higher-than-anticipated amounts of snow are due to a weaker-than-expected push of warm air from the south at upper levels, and a slower and weaker advance of warmer air from the east at the surface. Precipitation in the metro area should continue as snow this afternoon, possibly mixing with sleet and rain before tapering this evening. Northern and western suburbs will see the higher accumulations, while the normally warmer areas like downtown DC, Alexandria and points south will see less. Travel delays are likely throughout the afternoon into the early evening, especially during periods of heavier precipitation.
When/where will the heaviest frozen precipitation fall? Through mid-afternoon, with the highest accumulations in the north and west suburbs (places like Manassas, Leesburg, Centreville, Gaithersburg, Frederick).
Will the snow/ice accumulate? In the colder north and west suburbs is where the precipitation will accumulate the most. In the District, accumulations will be less, but even there road surfaces are likely to accumulate snow, particularly during heavy periods of precipitation.
Where is the precipitation now? Click here for the latest radar loop.
When will travel be most difficult? Through late afternoon -- particularly during heavy moderate and heavy precipitation.
Could there be power outages due to ice? Some isolated power outages are possible in the colder suburbs north and west of DC if freezing rain materializes during the afternoon and evening, but this won't be as big a problem as the last storm due to slightly warmer temperatures and less wind.
What about precipitation type? This is the most complex aspect of this storm to forecast. A mixture of snow and sleet is the most likely type this afternoon. Freezing rain now appears to be less of a threat in the immediate metro area although the north and west suburbs could see some icing this afternoon and evening.
When will conditions improve? In the metro area, most likely this evening, as precipitation tapers and temperatures stay at or slightly above freezing. However, in areas north and west, light freezing drizzle may linger overnight.
Could the storm bring more snow or ice than initially expected? Yes. Indeed, it already has.
What's the bottom line? A medium impact winter weather event is occuring, with significant snow/ice accumulations, particularly in the colder suburbs north and west of the city.
Nowcast 1:15pm: Moderate snow, possibly mixing with sleet and a bit of rain, is expected to continue over the next several hours before tapering this evening. The highest accumulations are expected in the colder suburbs, while in D.C. amounts will likely be less due to surface temperatures at or slightly above freezing. Even downtown, though, snow has been reported to be sticking to roads, especially during heavy bursts of precipitation.
...
Summary: With snow continuing to fall across the metro area, accumulations in the District are already being reported on the high end of the 0.5-2" predicted here late last night. In the immediate northern and western suburbs, accumulations have already surpassed the 2-3" predicted here, with reports of 3-5" and rising. Further west, in the mountains of West Virginia, accumulations in some locations have reached 6" or more.
The higher-than-anticipated amounts of snow are due to a weaker-than-expected push of warm air from the south at upper levels, and a slower and weaker advance of warmer air from the east at the surface. Precipitation in the metro area should continue as snow this afternoon, possibly mixing with sleet and rain before tapering this evening. Northern and western suburbs will see the higher accumulations, while the normally warmer areas like downtown DC, Alexandria and points south will see less. Travel delays are likely throughout the afternoon into the early evening, especially during periods of heavier precipitation.
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  Travelcast: Schoolcast (Mon.): | |
Frequently Asked Questions
When/where will the heaviest frozen precipitation fall? Through mid-afternoon, with the highest accumulations in the north and west suburbs (places like Manassas, Leesburg, Centreville, Gaithersburg, Frederick).
Will the snow/ice accumulate? In the colder north and west suburbs is where the precipitation will accumulate the most. In the District, accumulations will be less, but even there road surfaces are likely to accumulate snow, particularly during heavy periods of precipitation.
Where is the precipitation now? Click here for the latest radar loop.
When will travel be most difficult? Through late afternoon -- particularly during heavy moderate and heavy precipitation.
Could there be power outages due to ice? Some isolated power outages are possible in the colder suburbs north and west of DC if freezing rain materializes during the afternoon and evening, but this won't be as big a problem as the last storm due to slightly warmer temperatures and less wind.
What about precipitation type? This is the most complex aspect of this storm to forecast. A mixture of snow and sleet is the most likely type this afternoon. Freezing rain now appears to be less of a threat in the immediate metro area although the north and west suburbs could see some icing this afternoon and evening.
When will conditions improve? In the metro area, most likely this evening, as precipitation tapers and temperatures stay at or slightly above freezing. However, in areas north and west, light freezing drizzle may linger overnight.
Could the storm bring more snow or ice than initially expected? Yes. Indeed, it already has.
What's the bottom line? A medium impact winter weather event is occuring, with significant snow/ice accumulations, particularly in the colder suburbs north and west of the city.
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