Friday: Tornado, Wind, Hail Threats From Plains To East
A powerful low-pressure system is likely to spawn a dangerous outbreak of severe thunderstorms in portions of the Midwest, South and East, where tornadoes, widespread damaging winds, large hail and flash flooding are all concerns.
Big Picture
The storm system that will trigger this multi-day outbreak of severe weather is entering the West right now. It will spread through the central and eastern states Friday, Saturday and Sunday, with a severe weather threat each day.
In some cases, the threat of severe weather and tornadoes will be overnight, so be sure to know ahead of time where your safe shelter is and have multiple ways to receive warnings.
(MORE: Nighttime Tornadoes Twice As Likely To Be Deadly)
Friday-Friday Night Forecast
-Locations: Much of the Mississippi Valley as well as parts of the lower Ohio and Tennessee valleys are in the threat area highlighted by NOAA’s Storm Prediction Center below. Areas shaded red have the greatest risk of severe storms, including St. Louis, Paducah, Kentucky, Memphis, Tennessee, and Jackson, Mississippi.
-Timing: The threat of severe storms likely won’t begin until later in the afternoon on the western edge of the forecast shown below. From there, the potential for severe storms will spread eastward through the evening and overnight hours toward the eastern side of the threat areas.
-Threats: Swaths of intense damaging wind gusts, tornadoes (possibly EF2 or stronger) and large hail could accompany any storms that turn severe. Tornadoes might spin up within a line of severe storms and with any supercells that develop.
Friday – Friday Night’s Severe Thunderstorm Forecast
(Shaded on the map above is the likelihood of severe thunderstorms, according to NOAA’s Storm Prediction Center. Note that not all categories apply for the severe weather risk on a particular day.)
Saturday-Saturday Night Forecast
-Locations: The Deep South has the highest risk for severe storms, including parts of Alabama, Georgia, Louisiana, Mississippi, Tennessee and the western Florida Panhandle. That includes Atlanta, Birmingham, Huntsville and Montgomery, Alabama, Chattanooga, Tennessee, Jackson, Mississippi, and New Orleans. At least some severe weather could extend as far north as Ohio and western Pennsylvania.
Forecast guidance shows a potentially volatile setup that could produce dangerous supercell thunderstorms as well as one or more lines of severe storms in the South. The intensity of the afternoon and evening storms will depend on how unstable the atmosphere becomes, so expect changes to the forecast depending on that factor.
-Timing: Thunderstorms, a few of which could be severe, might be ongoing in the morning from parts of the South northward to the Ohio Valley. The most intense severe weather will unfold in the afternoon and into the overnight hours, spreading from west to east across the threat areas below.
-Threats: Tornadoes (possibly EF2 or stronger), numerous damaging winds gusts and large hail are all concerns. In addition, flash flooding from heavy rain could impact parts of Alabama, Mississippi, northern Georgia, Tennessee and Kentucky.
Saturday-Saturday Night’s Severe Thunderstorm Forecast
(Shaded on the map above is the likelihood of severe thunderstorms, according to NOAA’s Storm Prediction Center. Note that not all categories apply for the severe weather risk on a particular day.)
Sunday’s Forecast
-Locations: The cold front might produce additional bouts of severe storms from the mid-Atlantic states to the Southeast as the weekend ends. That includes Charleston, South Carolina, Raleigh, Philadelphia and Washington, D.C.
-Timing: Leftover storms from overnight, some possibly severe, will likely be ongoing in the morning in parts of the East. A combination of those storms possibly intensifying and new storms developing will keep the threat of severe weather going through the afternoon.
-Threats: Damaging wind gusts are the primary concern, but an isolated tornado is possible. Localized flash flooding could also occur in spots.
Sunday’s Severe Weather Forecast
(Shaded on the map above is the likelihood of severe thunderstorms, according to NOAA’s Storm Prediction Center. Note that not all categories apply for the severe weather risk on a particular day.)
Classic Setup
The setup is familiar for March and the rest of spring, with a sharp southward plunge of the jet stream swinging out of the West toward the central and eastern states.
At the same time, the jet stream energy helps to form a strong low-pressure system along a cold front that draws increasing moisture north from the Gulf.
That combination of ingredients triggers the formation of numerous thunderstorms, some of which could rotate and produce tornadoes in addition to widespread damaging winds and hail.
(MORE: Typical Ingredients For An Outbreak)