Fox News Weather Center

First widespread taste of cool fall air to sweep across southeastern US

The coolest air since the spring will sweep away haze and high humidity across the southeastern United States as this week progresses.

Highs in the 90s F will soon be a thing of the past for the Deep South. Cooler and less humid air will progress from northwest to southeast across the region.

When compared to the heat from this past weekend, temperatures in many areas of the southeastern U.S. will be shaved by 15-20 degrees by Thursday and Friday.

Even along the upper Gulf Coast and in northern Florida, temperatures will be shaved by several degrees and humidity levels slashed.

By Thursday and Friday, highs will range from the upper 60s in the southern Appalachians to the lower 70s over the Tennessee Valley to the middle 80s along the Gulf Coast and northern Florida.

Nighttime lows will be in the upper 40s over the southern Appalachians to the lower 50s in the Tennessee Valley, the middle to upper 50s over the Piedmont and the upper 60s to near 70 along much of the Gulf Coast late this week.

The cooler and less humid air will bring relief to those struggling without air conditioning. For those that have air conditioning, the upcoming weather will offer a chance to let in some fresh air.

A storm forecast to stall over the Ohio Valley and northeastern U.S. will be responsible for funneling the cooler and less humid air into much of the South.

Ahead of the cooler air, rounds of showers and thunderstorms will frequent areas from part of the Florida Peninsula to the immediate Atlantic coast.

Where downpours persist, there will be the potential for isolated flash flooding.

The forward progress of the cool air may slow near the Atlantic coast and could stall over the Florida Peninsula.

The advancing push of cool air may influence the path of a potential tropical system after it enters the Caribbean this weekend. A southerly flow ahead of the cool air may tug the tropical system northward.

Warmth is likely to build over the Southeastern states later this weekend into the following week, but most likely not to the levels experienced during much of September.

This month is likely to finish as one of the warmest Septembers on record for many locations in the South. For most cities in the South, September of 1925 was the warmest on record. This year September is likely to finish in the top five warmest for Atlanta; Birmingham, Alabama; Jackson, Mississippi; and many other locations. Individual city records date back to as early as the mid-1800s.

This follows the third-hottest summer on record for South Carolina and the fourth-hottest summer on record for Florida, according to the National Climatic Data Center (NCDC). Statewide temperature rankings date back to 1895.