Snowfall UpdateJanuary 23rd, 2013 at 1:10 pm by Tiffany Savona WAVY under Weather
After looking at the latest computer model data early this afternoon, not much has changed with the overall thinking with this quick moving upper level storm system. This system is currently producing light snow across portions of Illinois and Indiana. But when looking at just radar data, it looks like moderate to heavy snow is falling across the Midwest.
This can be very misleading, which is why this forecast is so tricky. Very dry air is in place all across the Midwest. Dewpoints are in the single digits or below zero, which indicates extremely dry air at the surface. While we have moisture in the middle levels of the atmosphere, this dry air at the surface is causing some of the snow to evaporate before reaching the ground. This is why your snow reports are so crucial, otherwise we do not have any ground truth to what is actually happening.
Our latest Future Trak model is trending farther south with the snow early Thursday morning. This makes sense because most of the snow is falling south of the upper level disturbance in the Midwest. So, this trend should continue when it moves across Virginia. Both the NAM and the GFS models focus more of the snow towards the Northern Neck. In fact the latest NAM decreases the snow chances for the Southside and North Carolina, but keeps the chances up around Reedville and Parksley. We think our Future Trak model is overdoing the snowfall because it is not taking into account the amount of dry air at the surface.
We have made a few adjustments to the snowfall forecast. The best chance for accumulating snow will be north of the Peninsula. The Middle Peninsula, Northern Neck and the Eastern Shore could see 0.5″-1.5″ of snow. The snow should begin an hour or two before midnight tonight across the northern areas and then move from north to south early Thursday morning. Hampton Roads cities, including the Peninsula, the Southside and N.E. North Carolina could see a dusting to about 0.5″ of snow. It will be cold enough for the snow to stick to grassy areas and roadways. So we may see some delays or slow downs during your Thursday morning commute. Don Slater will be in tonight to give you the latest on the potential accumulations. Stay tuned!
Meteorologists: Tiffany Savona & Jeremy Wheeler