Dew points have dropped significantly from Petersburg north toward Richmond, indicating drier air near the surface. Snow falling into this drier air is evaporating before it can reach the surface. A good example is at Petersburg, where light snow was falling from 1:40-2:20 a.m., but then the dew point temperature dropped from 25 degrees to 16 degrees in an hour and a half. It took a while for snow falling into this drier air to overcome and make it to the surface again without evaporating first, and light snow is now being reported again in Petersburg at 4:20 a.m. I expect this trend to continue in Southern and Central Virginia early Tuesday morning, as snow falling into the drier environment must "re-moisten" the lower levels and allow snow to make it to the surface.
Snow currently just south of the border will continue to expand northeastward into Virginia by mid-morning. I expect most of Central and South-central Virginia's snow to fall from mid-morning through early this afternoon. By late this afternoon, I expect snow to only be falling in Southeast Virginia, south of a line from Emporia to Smithfield. Some flurries may linger near this line through late afternoon, but will not significantly add to totals.
--Carrie
No comments:
Post a Comment