Post-tropical Isaias brings tornado, flood, and wind threat to Georgia today

A weakened but still dangerous tropical system is moving through Alabama this morning, pushing a wave of serious weather hazards across Georgia — including the threat of tornadoes, heavy flooding rain, and damaging wind gusts that could last into tonight.

What’s happening: Post-Tropical Cyclone Isaias was about 170 miles southwest of Atlanta and about 90 miles west-southwest of Columbus as of early this morning, moving north at 14 mph with maximum sustained winds of 35 mph. Though the storm has lost its tropical classification, it is still generating multiple active weather alerts across the state.

The tornado threat: A favorable setup for tornadoes is developing across Central Georgia and will push into North Georgia through the afternoon and evening. Several tornadoes are possible, particularly inside the storm’s outer rain bands. A stronger, long-track tornado rated EF2 or EF3 cannot be ruled out, especially across Central Georgia. Tornadoes from tropical systems tend to form quickly and with little warning, giving people less time to react.

The wind threat: A High Wind Warning is in effect for North Georgia, where east winds of 10 to 20 mph with frequent gusts of 40 to 50 mph are expected through the afternoon and into tonight. A Wind Advisory covers west central Georgia counties — including Muscogee, Troup, Heard, Meriwether, Harris, Talbot, Taylor, Chattahoochee, Marion, Schley, Macon, Pike, Upson, Stewart, Webster, and Sumter — with gusts up to 40 mph until 11 p.m. A separate Wind Advisory covers northeast Georgia counties including Rabun, Habersham, Stephens, Franklin, Hart, and Elbert, along with parts of western North Carolina and Upstate South Carolina, with gusts up to 46 mph until 8 a.m. Sunday. The strong winds are being driven by a pressure difference between Isaias and a high-pressure system sitting over the Mid-Atlantic region.

The flood threat: A Flood Watch covers all of North and Central Georgia. Widespread rainfall of 2 to 4 inches is expected across much of the area, with a localized band where as much as 8 inches could fall. Saturated ground combined with strong winds raises the risk of downed trees and power outages. In the mountains, heavy rain falling on already-wet soil could trigger landslides. The north-to-south orientation of the storm’s rain bands may also worsen river flooding along north-south stretches of rivers.

The coast: Dangerous rip currents are affecting Georgia Beaches, Beaufort, and Coastal Jasper until 8 p.m. today. Rip currents are fast-moving channels of water that can pull swimmers away from shore into deeper water. People should stay out of the ocean.

By the numbers:

• 35 mph: Isaias’s maximum sustained winds
• 40 to 50 mph: expected gusts in North Georgia
• 2 to 4 inches: widespread expected rainfall across North and Central Georgia
• Up to 8 inches: possible in the heaviest rain band
• EF2 or EF3: the strongest tornado that cannot be ruled out

What’s been canceled: Tropical Storm Warnings that were in effect for 16 west and central Georgia counties — including Muscogee, Troup, Meriwether, Harris, Sumter, and others — have been lifted. No tropical watches or warnings remain active for North or Central Georgia.

The path forward: Conditions will peak in intensity today and into tonight before the system continues north and weakens further. Both the National Weather Service office in Peachtree City and the one in Tallahassee, Florida, say their tropical cyclone statements issued this morning are the last they will issue for this event. The flash flooding and tornado risk remain the most serious concerns for the rest of the day.

Georgians can find emergency preparedness information at ready.ga.gov, ready.gov, or redcross.org.