TL;DR

The Storm Prediction Center has issued a Marginal Risk for severe thunderstorms across parts of the Southeast on Tuesday, September 22. Isolated severe wind gusts up to 75 mph are the primary threat. Activity will peak from mid-afternoon through early evening.

What's Driving Today's Severe Weather?

Meanwhile, a slow-moving cold front is dragging across the Deep South into the southern Appalachians, focusing thunderstorm development across the Southeast. Surface dewpoints in the upper 60s to lower 70s, combined with afternoon heating, will yield 1500 to 2500 J/kg of mixed-layer CAPE by early to mid-afternoon. Weak mid-level flow will limit overall storm organization, but water-loaded downdrafts from the stronger cells can still produce locally severe wind gusts.

Where Is the Marginal Risk Today?

The NOAA Storm Prediction Center (SPC) has outlined a Marginal Risk area in its Day 1 Convective Outlook:

  • Southeast — spanning parts of the Deep South into the southern Appalachians, including portions of Alabama, Georgia, Tennessee, and South Carolina

Cities in the Southeast risk area include Birmingham, Huntsville, and Chattanooga, which are among the metros that could see thunderstorms capable of strong to locally severe gusts.

When Will Storms Develop?

Southeast Timing

Thunderstorms will fire along and ahead of the cold front during the early to mid-afternoon, with the severe threat continuing into the early evening. Peak activity is expected between 1 PM and 7 PM local time across the region.

What Hazards Should You Expect?

Damaging wind gusts are the primary severe weather threat. The SPC notes that water-loaded downdrafts in the Southeast may produce strong to locally severe gusts and pockets of wind damage.

Tornadoes are not expected today. Weak low- to mid-level flow in the Southeast will keep the tornado threat at zero.

Yesterday's Severe Weather: Wind Dominates

Monday's severe weather was driven almost entirely by wind, with 127 wind reports spanning 14 states from West Virginia to Texas. The bulk of the damage consisted of downed trees and power lines, with scattered reports of structural damage including roof materials blown off condos near Cropwell, Alabama, and a tree falling through a house on Knollwood Drive near Mount Airy, North Carolina.

Hail was far less common, with just 12 reports—all quarter-size or slightly larger—concentrated in Texas, Alabama, and the southern Appalachians. No tornadoes were reported.

The pattern mirrors today's setup: marginal instability, weak shear, and pulse-type storms capable of brief bursts of damaging wind but little else.

What Should You Do?

If you're in the Marginal Risk area today, monitor radar and local NWS forecasts through the afternoon and early evening. Severe thunderstorm warnings may be issued for the strongest cells, and you should move indoors immediately if a warning is issued for your location.

Outdoor plans—especially in exposed areas like hiking trails, golf courses, or open fields—should include a way to receive warnings and a plan to reach shelter quickly. Lightning is a threat with any thunderstorm, not just the severe ones.

If you're at home tonight and storms are forecast for your area, make sure your phone's Wireless Emergency Alerts are enabled. Most smartphones allow tornado and severe thunderstorm warnings to break through Do Not Disturb by default, though third-party weather apps are silenced unless you've configured exceptions.

Tomorrow's Outlook

The SPC has not issued a categorical severe weather risk for Wednesday, September 23. The upper trough will continue moving east across the Rockies, but instability and shear are expected to remain too limited for organized severe weather. Isolated strong storms are possible, but widespread severe weather is not anticipated.

VORTEX is a free web app at vortexintel.app that monitors severe weather nationwide. Pro ($4.99/month) places phone calls to your phone when a tornado or flash flood warning is issued for a location you care about — calls can ring through Do Not Disturb once you enable Emergency Bypass for the number, unlike most third-party app notifications.