Wednesday, December 10, 2008

Snow Tomorrow?

Snow is the buzz and the big question tonight in the Mid-South tonight. I am confident that the answer is "yes", there will be snow. Confidence is low regarding exactly how much and where it will occur. Models show a cold core upper low pressure will advance northeastward from eastern Texas through Louisiana, Mississippi, and Alabama. These systems deliver their own cold air from above.

There is a winter storm warning for much of Mississippi and a winter storm watch in northwest Alabama. One to three inches of snow is expected in these areas. These systems are very difficult when it comes to predicting specific details regarding the amount of accumulation and exact placement of the heaviest snow.

Based on historical analogies, I would not be at all surprised if there is a narrow band of six inches or more of snow somewhere in these watch or warning areas.

The best discussion of the forecast issues I have seen tonight is by Justyn Jackson, a meteorology instructor at Mississippi State University.

He says this about the forecast for Starkville:

"Although the upper low will not be directly over us, very strong upward motion will cause dynamic cooling to occur. This will allow the temperature profile to cool enough for wet snow to begin after 11 a.m. in Starkville. Surface temperatures will likely remain just above freezing so it may be initially tough for snow to stick on the warm ground. However, given the impressive vertical motion forecast by all the models, a burst of heavy snow is likely, which will likely allow a thin layer of snow to cover the ground. When this occurs, it should be no problem for additional snow to accumulate on the surface. Additionally, with a heavy burst of snow, the surface temperature should begin dropping and be around 33 by early afternoon. The heavy snow may continue through most of the afternoon before tapering off around 5 p.m."

Stay tuned for more tomorrow!

No comments: