Tornadotony.com
Day 2 Severe Weather Outlook
Valid from 6 AM CST Monday, March 3rd, 2008, to 6 AM CST Tuesday, March 4th, 2008
Issued: Saturday, March 1st, 2008, at 11:00 PM CST

There is a Moderate Risk of severe thunderstorms for far southeastern Texas, much of Louisiana, southeastern Arkansas, most of Mississippi, and western Alabama.

There is a Slight Risk of severe thunderstorms surrounding the Moderate Risk and extending northward in southwestern Tennessee.

Mid-South/Lower Mississippi Valley
The stage will be set for a potentially violent severe weather outbreak from Monday morning through Tuesday morning.

Intense convection, in the form of a squall line and possible embedded supercells, will be ongoing at the start of the period from western Arkansas by 12z Monday. Further south and southwestward, the atmosphere will be capped prior to frontal approach. As the front approaches, it is anticipated that convection will develop along it. Given that forcing will not be terribly strong, a mixed mode of embedded supercells and bows are possible, with damaging winds and tornadoes. Although it looks most likely that this will be in western or central Louisiana at this time, I have opted to pull the moderate risk into southwestern Texas as the models trend slower with the system.

The greatest threat to life and property will be ahead of the squall line in the free warm sector Monday afternoon and night. Minimal capping and inhibition will be in place here. SBCAPE of 1500-2000J/kg or more are likely up to about Jackson, Mississippi, with 500-1500J/kg SBCAPE possibly extending as far northwestward as Pine Bluff, Arkansas. These moderate-strong instability values will be in place in an environment with extreme wind shear through all levels of the atmosphere. Conservative estimates indicate 0-1km SRH values of 200-400m**2s**-2 with 0-6km shear of up to 70kt in the Moderate Risk region. The region will also be in the right-front quadrant of the jet disturbance, which will lend to lesser VV, lesser forcing, and greater tendencies for cells to remain discrete. An outbreak of intense supercellular thunderstorms is anticipated ahead of the squall line, with very large hail up to softball-size, winds up to 80 MPH, and strong to potentially violent tornadoes all possible.

As the activity continues overnight, the squall line is expected to accelerate eastward. As instability diminishes toward morning, the line should overtake discrete convection and progress to just east of the Alabama-Georgia border by 6 AM Tuesday. A few tornadoes and damaging winds will still be possible with the line.

THIS IS NOT AN OFFICIAL FORECAST. Please consult the Storm Prediction Center or your local National Weather Service office for official critical and life-saving information.