From SPC: Marginal Risk Of Severe Storms For A Good Portion Of The Southeast Today

There is a Marginal Risk for severe storms up today through 7:00 am tomorrow morning for not only all of Central Alabama but for the entire state of Alabama. For us in Central Alabama, the main window for severe storms will be from midnight tonight through 12:00 pm on Thursday. The main threats will be from isolated damaging wind gusts up to 60 MPH and a brief tornado or two.

We are already starting to see some active storms to our west in Mississippi as a few cells have gone severe over the past hour or so. One of those cells is currently crossing over the state line and moving into the western portions of Pickens County. A Significant Weather Advisory has been issued until 9:15 am for that cell.

Here is the text from the Storm Prediction Center about the Marginal Risk for severe storms:

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0751 AM CDT Wed Oct 30, 2019

Valid 301300Z – 311200Z

THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THROUGH TONIGHT FROM THE NORTHERN GULF COAST TO THE TN VALLEY.

SUMMARY
A few strong to severe thunderstorms are possible during the day across the northern Gulf Coast states, with a threat evolving overnight into parts of Tennessee. Localized wind damage or a brief tornado will be possible.

Northern Gulf coast to TN Valley through tonight…
A pronounced midlevel shortwave trough over CO will progress eastward toward MO tonight while strengthening and taking on a more neutral tilt. Surface cyclogenesis is expected downstream from the midlevel trough, across the lower OH Valley overnight along a pre-existing baroclinic zone. South of the developing cyclone, the cold front will begin to surge eastward tonight across the lower MS and TN Valleys.

Low-level moisture is spreading north-northeastward this morning across southern MS/AL, and the warm sector should expand northward into the TN Valley by tonight. Some surface heating will occur today across central/southern MS/AL where cloud breaks occur in the warm sector. However, the warm-advection pattern observed this morning, and related low-level shear will tend to weaken through the afternoon. The net result will be a low-end threat for rotating storms this morning near the coast and within the expanding warm sector inland later today, with the possibility for isolated strong gusts and/or a brief tornado.

Overnight, convection should begin to organize in a band along the surging cold front from northeast MS into northern AL and middle TN. Low-midlevel lapse rates will be poor, but weak surface-based buoyancy will be driven largely by boundary-layer dewpoints in the upper 60s north to lower 70s south. Strengthening deep-layer flow/vertical shear in conjunction with the OH Valley cyclogenesis, and the weakly unstable warm sector (MLCAPE near 500 J/kg) will favor some threat for damaging gusts with the frontal convection, mainly after 06z (1:00 am).

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