Severe Thunderstorm Outbreak, Including Tornadoes, Forecast in the South, Mississippi and Tennessee Valleys Tuesday

Quincy Vagell
Published: February 1,2016




 
Groundhog Day 2016 may feature an outbreak of severe thunderstorms, including some tornadoes, from the northern Gulf Coast to the Ohio Valley.
At the same time, a swath of heavy snow with blizzard conditions will be ongoing to the north and northwest with Winter Storm Kayla.
(MORE: Winter Storm Kayla Targets Plains, Upper Midwest)

Severe Weather Setup

A sharp, southward plunge of the jet stream will swing out of the Desert Southwest into the Southern Plains and Deep South early this week.
In response, surface low pressure will intensify, tracking from the Plains into the Great Lakes, drawing warm, moist air north from the Gulf of Mexico.
The strong wind fields associated with the jet stream will combine with modest amounts of instability (warm, moist air in low levels and colder, drier air in the upper levels of the atmosphere) to support a threat of severe thunderstorms.
The extent of destabilization on the warm side of Winter Storm Kayla will influence how widespread and significant the severe threat could become, particularly regarding the threat of tornadoes.
Below is an outline of when and where severe thunderstorms may develop.

Severe Weather Forecast

Monday Night

• Scattered thunderstorms may flare up over parts of the southern Plains, including north-central Texas, Oklahoma and southeastern Kansas and then may push east into the Ozarks after midnight. 
• At this time, only a few of these late night storms could produce a brief high wind gust and hail.

Monday Night's Severe Threat

Tuesday

• This will be the most active day for severe thunderstorms.
• Numerous thunderstorms are expected ahead of an advancing cold front from the lower and mid-Mississippi Valleys, Ohio Valley, and northern Gulf Coast.
• Afternoon and Evening Threat Areas: Severe storms will rumble across parts of eastern Arkansas, southeastern Missouri and Louisiana into Mississippi, Alabama, Tennessee, Kentucky, southern Illinois, and central and southern Indiana.
• Overnight Threat Areas: The chance for severe storms should linger overnight in a swath from southeastern Indiana through central Kentucky, middle/east Tennessee, northwest Georgia, Alabama, east and southern Mississippi, southeast Louisiana and the western Florida panhandle.
• Main Threats: Damaging wind gusts, large hail and at least some tornadoes could develop in this environment. Uncertainty exists regarding the number of tornadoes. There is a potential for long-track strong tornadoes given the strong wind fields forecast. By late night, slow-moving thunderstorms may trigger flash flooding along the southern flank of the squall line.

Tuesday's Severe Threat

Wednesday

• As the cold front slices east, thunderstorms are likely to flare up from parts of the mid-Atlantic states into the Southeast, from the Delmarva peninsula to the northern Gulf Coast.
• The severe threat will likely be much less significant than Tuesday, but at least a few severe thunderstorms with strong, straight-line winds, and perhaps a tornado appear possible, along with the threat of local flash flooding.

(MAPS: 10-day Forecast)

Wednesday's Severe Threat

Thursday

• A slow moving cold front will bring the risk of an isolated severe thunderstorm to Florida.

Current Radar with Watches and Warnings

Trees were downed by high winds in the Mission Bay section of San Diego, California, on January 31, 2016.
(Steve Hargis)

Storm Reports So Far

On Sunday afternoon, as low pressure moved into Southern California a couple of trees were downed west of Santa Paula, California which trapped six vehicles due to wind gusts during a thunderstorm.
A tree also came down near Burbank across highway 134, which blocked a three to four lanes of the freeway.
Non-thunderstorm winds also caused damaged across Southern California and one death was reported due to a falling tree.
Near Santa Barbara, California flash flooding with mud and rocks across highway 154 was reported.
(MORE: Latest Severe Weather Impacts)

A Rare Early Risk Area

This prompted the Storm Prediction Center to issue a rare day 7 outlook Wednesday for the Groundhog Day severe potential. This is done only in cases where there is relatively high confidence that far out in time of organized severe thunderstorms, or concern for an outbreak.
According to Dr. Patrick Marsh of the National Severe Storms Laboratory, the last time the SPC highlighted a severe risk area on day 7 was July 14, 2013. It's only the 11th time that has been done since late April 2008.
National Weather Service meteorologist Taylor Trogdon compiled all previous cases since 2008 when the SPC outlined a severe risk area in their day 7 outlook.
An outbreak often, but not always, results, with some cases featuring a swarm of tornadoes, while others feature few tornadoes.

The Storm Prediction Center later issued a 30 percent day 5 outlook on Friday for the potential severe weather outbreak. This is the highest-tier outlook that can be issued so far out, further suggesting that there is high confidence in severe weather on Tuesday.
Check back with us at weather.com for updates on this potential severe weather outbreak.

PHOTOS: January Cape Coral, Florida Tornado