Sunday, February 20, 2005
Storm update: Pride goeth before a fall
Jason Samenow @ 12:15 AM
All week, we've been forecasting the possibility of some wintry precipitation for Sunday into Monday. Josh and I have been a little bit more bullish about the possibility of accumulating snow whereas Dan and Steve have been more cautious and suggested more of a rain event. Put one in the win column for Dan and Steve. While there is very likely to be a period of snow and/or frozen precipitation (sleet/freezing rain) late Sunday afternoon and evening, I expect little or no snow accumulation for the DC area.
The reason we will not get significant snow from this storm is pretty simple -- winds will be southerly (and it will be howling -- especially about 5000 feet above us -- the precipitation has to fall through this layer). DC simply does not get good snowstorms with a southerly wind -- even if there is some cold air in place at the onset. A southerly wind means the storm is passing to our north - driving away the cold area of high pressure in eastern Canada or New England that we must have for a meaningful snow event.
Not only does a more northerly storm track mean more warm air it also means less precipitation. It now appears the heaviest precipitation from this storm will fall north of the Mason Dixon line. We may get "dry slotted" and receive less than 0.25" of melted precip total.
Here's what I see happening
For the record, here is what other forecasters are calling for:
Channel 4 (Veronica Johnson): 1-2" of snow
Channel 7 (Joe Witte): 1-3" of snow
Channel 9 (Tony Pann): 1-3" of snow
National Weather Service: 2-4" of snow
 | Overall storm assessment Storm Impact: |
The reason we will not get significant snow from this storm is pretty simple -- winds will be southerly (and it will be howling -- especially about 5000 feet above us -- the precipitation has to fall through this layer). DC simply does not get good snowstorms with a southerly wind -- even if there is some cold air in place at the onset. A southerly wind means the storm is passing to our north - driving away the cold area of high pressure in eastern Canada or New England that we must have for a meaningful snow event.
Not only does a more northerly storm track mean more warm air it also means less precipitation. It now appears the heaviest precipitation from this storm will fall north of the Mason Dixon line. We may get "dry slotted" and receive less than 0.25" of melted precip total.
Here's what I see happening
- A brief burst of snow between 4 and 8pm
- The snow will quickly mix with and change to sleet (probably within an hour or two of starting)
- The heaviest precipitation will fall north of Baltimore and it will last longer there as well
- In and around DC, the precipitation will become light and scattered after about 11pm
- Any frozen precipitation will turn to liquid (i.e. rain) between 2am and 5am -- but will be quite light
- Presidents' Day will be cloudy and dreary with highs 40-45
For the record, here is what other forecasters are calling for:
Channel 4 (Veronica Johnson): 1-2" of snow
Channel 7 (Joe Witte): 1-3" of snow
Channel 9 (Tony Pann): 1-3" of snow
National Weather Service: 2-4" of snow
Comments are closed for this archived entry | Link | 
Email this post
Email this post
