Friday Midday Forecast

We've certainly had a rainy start to our Friday across the GTR as rain has filled in nicely across the area this morning. Why all this rain? 

Here's the 500mb vorticity analysis. There is a short wave in the mid-levels of the atmosphere, and the associated fort max is located on the AR/LA border. Significant downstream uplift from this feature is likely driving force  for the rain this morning. 

Also, if you notice in the surface observations, a weak surface low seems to be spinning up over parts of southwestern Alabama, just to the southeast of Meridian, MS. Additionally, a psuedo-warm front-type structure extends to the northeast, and moisture is, in essence, overrunning this feature and is also combining with the aforementioned uplift to produce widespread rain this morning. 

Here's the potent shortwave for the last part of the weekend. Notice a slight negative tilt to the trough, with over a 100kt wind max in the base of this trough that is progged to spread across the Ohio River Valley. 

This shortwave will bring some severe weather from the Tennessee Valley all the way to the Great Lakes. 

The primary dynamics associated with this system will be well to our north, but the SPC has included us here in the GTR in their standard slight risk of severe weather. An analysis of the severe weather parameters reveal, again, the highest threat will be to our north. 

But, instability will be higher (relatively) than the past few events we have. Forecasted CAPE values are between 500-1000 J/KG but with weaker dynamics. 

The 0-6km shear values are much higher to our north, but notice the shear vectors are due west across our area. This suggests the deep layer wind field will be flowing across the approaching frontal boundary, so isolated supercell storms seem to be the most probable convective mode, especially for areas in north MS into the Ohio River Valley. 

For us here in the GTR, I can't rule out an isolated severe storm, but the highest threat will be in areas to our north. 

Have a great Friday, and stay dry!

IW