Portions of North/Central Alabama Have Been Upgraded to a Slight Risk for Tonight

The Storm Prediction Center has decided to upgrade the north and northwestern parts of North/Central Alabama to a Slight Risk (level 2 of 5) for severe storms for tonight through the overnight hours. The slight risk includes locations west of a line from Geiger to West Jefferson to Hytop. A Marginal Risk (level 1 of 5) extends south of that to the I-85 corridor in the southeastern parts of the area. Here is the latest update from the SPC:

A few severe thunderstorms are possible this evening within a corridor across northeastern Mississippi and northwestern Alabama into middle Tennessee. This includes a risk for potentially damaging wind gusts and perhaps a couple of tornadoes.

Low-level moisture return is ongoing on southerly return flow across the lower Mississippi into Tennessee Valleys. This appears to be contributing to modest boundary-layer destabilization (including CAPE up to 500-1000 J/kg), which is expected to continue developing northeastward as an initial short wave impulse, which has emerged from the Southwest, progresses east-northeast of the central Great Plains late this afternoon and evening. As the associated frontal wave migrates into the lower Ohio Valley, there appears a window of opportunity for vigorous convective development focused along/just ahead of the trailing surface trough across Tennessee into Mississippi. This may coincide with a 40-50 kt southerly 850 MB jet axis, along which enlarged low-level hodographs may become supportive of supercells structures accompanied by the risk for damaging wind gusts and/or a couple of tornadoes. With the influence of the mid/upper forcing on the warm sector expected to be glancing/short-lived, it appears this risk will be maximized this evening, but at least some severe weather potential may linger as remnant convection spreads eastward/southeastward overnight.

NWS Huntsville updated graphic:

A few strong or severe thunderstorms are possible this evening into the overnight hours. The primary hazards will be strong (40-55 mph) to damaging winds (up to 60 mph) and small hail. There is a low risk of a tornado. A broken line of thunderstorms will move into northwest Alabama between 6-8 PM, cross the I-65 corridor between 8-10 PM, and exiting northeast Alabama by or shortly after Midnight. At this time, a Severe Weather Watch is not anticipated, but please keep aware of the weather situation and any updates this evening.

NWS Birmingham updated graphic:

There is a risk of severe thunderstorms from 7 pm tonight to 5 am Tuesday for locations near and northwest of Interstate 85. Threats include a few tornadoes, damaging winds up to 60 mph, and hail up to quarter size.

Category: Alabama's Weather, ALL POSTS, Severe Weather