Severe Thunderstorms Target Storm-Weary South Wednesday and Thursday (FORECAST)

Jon Erdman
Published: March 22,2016

The first week of spring will feature a robust spring storm system bringing a threat of more severe thunderstorms and heavy rainfall to storm-weary parts of the South, and also into parts of the Midwest. This system will also have a snowy side, Winter Storm Selene, which can you read more about here.
(MORE: Don't Ignore Severe T-Storm Warnings)
The severe weather setup for midweek features a deep, sharp southward dip in the jet stream, or upper trough, pushing out into the Plains states. At the surface, a strong low-pressure system will tap warm, moist air from the Gulf of Mexico.
Converging air ahead of the cold front, along a dryline ahead of the front, and near the warm front will give lift for thunderstorms. Changing winds with height known as wind shear may allow thunderstorms to initially become supercells.

Ingredients For Severe Thunderstorms This Week

Damaging winds and large hail will be the main threats from any severe storms that develop, though isolated tornadoes are also possible.
Below is our latest forecast thinking on the timing and magnitude of the severe threats this week.

Severe Weather Outlook

Wednesday

• Scattered severe t-storms may flare up Wednesday afternoon into Wednesday night from the lower Ohio Valley and middle Mississippi Valley to eastern Texas.
• Damaging thunderstorm winds and large hail will be the main threats, though isolated tornadoes are possible. Currently, the highest risk of tornadoes appears to be from southeastern Oklahoma and northeastern Texas into western Arkansas, northwest Louisiana and southwest Missouri.
• CITIES: St. Louis | Little Rock | Shreveport, Louisiana | Houston

Wednesday Night's Forecast

Thursday

• Thunderstorms should be numerous from the Deep South northward into the Ohio Valley.
• The greatest threat of severe storms is focused on the Gulf Coast states and Tennessee Valley, where instability will be the greatest.
• Again, damaging winds and large hail will be the main threats, though isolated tornadoes are also possible.
• Given still-saturated ground from the March 7-12 heavy rain event and last week's scattered storms, if the frontal system moves slower, flash flooding is also a threat.
• CITIES: Houston | Monroe, Louisiana | New Orleans | Birmingham | Nashville

Thursday's Forecast

(MAPS: 7-Day Rain/Snow Maps | 10-Day Highs/Lows/Weather)

South Pounded By Flooding and Severe Weather in Recent Weeks

Sometimes it seems an area can't get much of a break from the weather pattern. It's as if they're a meteorological punching bag.

Estimated Rainfall This Month

So goes parts of the Lower Mississippi Valley and Southern Plains in recent weeks.
Roughly two weeks ago, an early March deluge of locally over 20 inches of rain triggered massive flash flooding and river flooding from parts of east Texas to Arkansas, Louisiana, Mississippi and west Tennessee, setting record flood crests along the Sabine River.
(RECAP: Record Flooding in Parts of the South)
In fact, that river flood event continues. As of this writing, numerous locations in the Lower Mississippi Valley are still above flood stage, a few still in "major" flood.
Then last week, not one but two hailstorms pelted the Ft. Worth, Texas metro area, smashing car windshields, even punching holes in some roofs.
(RECAP: Impacts From Damaging Hailstorms)
If that wasn't enough, a severe thunderstorm dumped piles of hail on West Monroe, Louisiana, Friday, one week after receiving over 20 inches of rain.

Then there's the tornadoes.
The Weather Channel severe weather expert, Dr. Greg Forbes, estimates a preliminary count of 142 tornadoes have occurred in the U.S. from February 1 through March 17, about 84 percent above the 20-year average count for that late-winter time period.
This is a far cry from last March. Not a single severe thunderstorm or tornado watch was issued anywhere in the nation the first 24 days of March 2015, something that had never happened dating to 1970, according to then NOAA Storm Prediction Center warning coordination meteorologist Greg Carbin.
But that was last year, and March is a prime tornado month in parts of the southern Plains and a corridor known as "Dixie Alley" in the Deep South.
(MORE: Your Monthly Tornado Risk | Your Odds of Being Hit by a Tornado)
MORE: Southern Flooding, Severe Weather March 8-10, 2016 (PHOTOS)