The wPC is concerned about the potential for flash flooding across parts of the region as storms develop and train over the same areas. The cold front that is slated to move through the area will tend to slow down a bit as it drops south and storm motion may end up riding along the front.
That will lead to storms continually moving over the same areas and may result in some flash flooding.
From the WPC:
Discussion…An upper trough passing through the Midwest with an incoming shortwave across OK and central TX have led to divergence aloft and 1000-2000 J/kg of MU CAPE from western MS southwest into southeast TX. Precipitable water values in the region are 1.5-1.7″ per GPS data and JAN/LCH raobs, which also show the requisite deeply saturated profiles and fairly unidirectional flow normally seen with possible training. Effective bulk shear of 35-50 kts should continue to organize convective activity. Radar imagery recently shows backbuilding convection a bit ahead of a cold front across central MS downstream of this instability pool.
The concern is that pre-frontal convection will attempt to backbuild and train for a bit before the cold front can catch up and sweep the activity southeast. Eroding instability should force heavy rain related issues southwest through the MPD area with time. While mesoscale guidance generally advertises local amounts in the 3″ range, places farther northeast in TN, KY, and OH managed hourly rain totals to 2.5″ with local 5″ amounts where mesocyclones managed to hold up convective progression, and see little reason why similar wouldn’t happen in MS, LA, and southeast TX this morning where ingredients appear equally supportive. Due to recent dryness over much of the lower 48 over the past month, soils are parched, so issues look most likely in urban areas.
