Chattanooga, Tennessee – A surge of colder air moving into the Southeast could bring frost concerns to parts of the Tennessee Valley during St. Patrick’s Day week, putting early spring vegetation at risk just days before the start of spring.
According to the NOAA Climate Prediction Center’s 8–14 day outlook, the period from March 15 through March 21 favors below-normal temperatures across much of the eastern United States, including northern Alabama, northwest Georgia and southern Tennessee. The pattern forms as a broad cold boundary drops south from the Great Lakes toward the Gulf Coast, allowing cooler Canadian air to settle across the Tennessee Valley.
If skies clear behind passing weather systems, overnight temperatures could fall into the mid-30s with isolated valleys briefly reaching 32°F, creating conditions supportive of patchy frost across the region.
Communities including Chattanooga, Huntsville, Dalton, Scottsboro and Fort Payne could see the greatest frost potential during calm early mornings. Valleys along the Tennessee River basin and Appalachian foothills tend to cool quickly and may experience frost first.
Drivers along Interstate 24, Interstate 75, and U.S. Highway 72 will likely notice the colder mornings, though the larger concern could be for gardens, orchards, and early spring crops across the Tennessee Valley.
Residents may want to cover sensitive plants overnight or bring potted plants indoors if frost advisories are issued.
The timing is notable as daylight saving time begins this weekend, yet winterlike mornings could still settle across the Tennessee Valley even as the first day of spring arrives later that week. Forecasters will continue monitoring overnight temperatures, and frost advisories could be issued if the colder pattern strengthens across the region.
