Irma’s flooding rainfall, tornado threat to expand from Florida to Georgia, Tennessee

By Jordan Root for AccuWeather.com

After blasting the Florida Peninsula over the weekend, Irma will track inland across the southeastern U.S., threatening flooding, damaging winds and severe weather over a large area.

Irma will put many lives at risk well inland from the coast. Residents in northern Florida, Alabama, Georgia, Tennessee and South Carolina should anticipate severe impacts from Irma.

Irma is forecast to track near the Gulf coast of Florida and inland near Tallahassee through Monday morning. From there, Irma will track across Georgia and Alabama Monday into Tuesday. 

Wind gusts of 60 to 80 mph, with locally higher gusts possible, will spread from Florida to southern Georgia and southeastern Alabama Monday.

“The tropical-storm-force winds should expand outward, especially on the east side, to over 300 miles on Monday,” AccuWeather Hurricane Expert Dan Kottlowski said.

Wind of this magnitude can down trees and power lines and cause damage to weak structures.

Occasional gusts between 40 and 60 mph will be felt across eastern Tennessee, northern Alabama and Georgia, including the cities of Atlanta, Knoxville, Tennessee; Chattanooga, Tennessee; Birmingham, Alabama; and Augusta, South Carolina.

People could face power outages, some of which may be lengthy. Now is the time to make sure flashlights are in working order and stock up on extra batteries.

Downed trees can also lead to road hazards for motorists. Alternative routes may need to be taken for those who must travel.

More from AccuWeather: 
Reports: Irma inundates Jacksonville, Florida, with record-shattering flooding 
Preparing for the costliest weather disaster in the US: How to stay safe before, during and after a flood 
The difference between tornado watches and warnings

Irma’s winds will cause water to pile up along the northern Florida, Georgia and Carolina coasts through Monday, inundating coastal communities with several feet of water, including Jacksonville, Florida; Savannah, Georgia; and Charleston, South Carolina.

Irma will dissipate to a tropical depression and eventually a tropical rainstorm over Alabama and Tennessee.

While widespread damaging winds will become less of a concern farther inland, the threat for flooding will mount as Irma's rain expands.

Irma will also bring a heavy swath of rain that will bring flooding across the Southeast and into the Tennessee Valley through the middle of the week.

“Heavy rainfall of 8-16 inches with localized amounts of 20-25 inches will bring life-threatening inland flooding,” Kottlowski said.

Heavy rain will bring an increased risk for flash flooding and mudslides across the southern Appalachians as Irma’s moisture surges into the mountains.

Small streams and rivers could overflow out of their banks and flood neighboring land and homes. Motorists will need to watch out for road washouts.

“What is left of Irma is expected to slow down and perhaps stall for a time in Tennessee and Kentucky,” Kottlowski said. 

This amount of rain will loosen the soil and will make it easier for wind gusts to topple trees in some areas.

In addition to heavy rain, some areas will have to worry about quick tornado spin-ups within Irma’s outer rain bands to the northeast of the storm’s center.

“These short-lived tornadoes will continue to develop across parts of South Carolina and Georgia on Monday," Kottlowski said.

These type of tornadoes are especially dangerous due to their quick formation and dissipation. Residents will need to quickly take shelter should one form in the area. Heed all severe storm and tornado-related warnings.

Read Full Story