We have a big system moving in from the West that will bring a lot of rain and possibly severe weather. 

The Basics:

A slow moving front will enter the area tomorrow.  An area of low pressure will move along that, and force a lot of moisture into a cooler airmass with it’s counterclockwise flow.  The whole are will see 1-3 inches of rainfall.  A flood watch starts tonight (Wednesday night), and lasts through Thursday night for parts of the area.  Namely for: Southampton county, Isle of Wight, the Peninsula, Eastern Shore, and all points Northward.  Rainfall amounts up to 4 inches are possible in the watch area.  Also we are in a slight risk for severe weather.  There’s lots of strong low level winds shooting warmth and moisture into the front.  If the front wavers a little further south, then the Flood Watch may have to be moved southward as well.

The Advanced:

The Hydrometeorological Prediction Center (HPC) has a pocket of 4 inches+ from Richmond up to the Northern Neck.  The computer models all dump good amounts of rain through the region.  We haven’t had a big rain event lately, so the ground should be able to hand the amounts for the most part.  However, we can easily get some downpours that will create localized flooding.  I’m not thinking that there will be a good chance for severe weather, but there is a chance.  The low level jet will be strong, but the winds look fairly unidirectional above 850mb.  Plus, the low that rides up the front will really occlude.  There will be cloudy skies all day.  So the instability will be low.  The low will be in the sweet spot somewhat, but it is a broad area of low pressure.  We’ll have some low cloud decks which can help to create funnel clouds, so that’s not good if we get the upper level support.  There may be a pocket of severe just east of the low where there may be some good veering in the lower levels.  Finally there will be a good jet at 300 mb riding up through the Mid Atlantic.  However it’s on the East side of the trough and the timing of it may not match the low moving through.  Much cooler weather will move in for Friday.  I’ll try to update the blog tomorrow when I get a chance.  Much cooler weather will move in for Friday.