Updated

The Latest on the threat of severe weather across the Southeast (all times local):

3:55 p.m.

The National Weather Service has issued a tornado watch for parts of three Southeastern states and says the region faces a particularly dangerous situation.

The watch covers all of north Alabama including the cities of Birmingham and Huntsville, plus smaller areas in northeastern Mississippi and southern Tennessee. It expires at 11 p.m. CDT.

Forecasters say the storm threat is unusually dangerous because of the possibility of several tornadoes, some of which could be intense. The weather service says hail as large as 3 inches (7 centimeters) in diameter could fall, and there's a possibility of wind gusts to 70 mph (110 kph).

Forecasters already have reported hail in Mississippi, and they issued a tornado warning for a section of northwestern Alabama.

Temperatures will turn cooler Tuesday after a cold front passes.

___

1:15 p.m.

A strong thunderstorm has begun dropping hail in northern Mississippi as the Southeast braces for a round of storms that threaten to bring strong tornadoes.

In Mississippi on Monday, the National Weather Service reports hail near Ripley, while radar indicates hail fell along a 50-mile (80-kilometer) path from Holly Springs to Booneville. The storm has tracked all the way across the state from west to east, decreasing in severity as it nears Alabama.

Pictures posted to social media showed as many as several inches of pea-sized hail in some places.

Twenty-nine million people face a threat of severe storms that could bring damaging hail, high wind and even tornadoes to the southeastern United States.

___

11:20 a.m.

Forecasters say there's increasing confidence that strong tornadoes could rumble across parts of the South — especially northern Alabama.

In a mid-morning update Monday, the national Storm Prediction Center said the risk appeared increasingly likely for "several tornadic supercells" to traverse northern parts of Alabama.

The region is in the bulls-eye of a larger area under threat of severe weather Monday afternoon that also included parts of Tennessee, Mississippi and Georgia.

Twenty-nine million people faced a threat of severe storms Monday that could bring damaging hail, high wind and even tornadoes to the southeastern United States.

___

8:20 a.m.

Schools are closing early in the southeastern United States because of the threat of severe weather including tornadoes.

More than a dozen school systems in northern Alabama announced they're dismissing students early Monday because of a line of storms forecasters say will move through the area. Scattered early-closings extend into central Tennessee.

Other school systems say they're monitoring conditions and could release students early if conditions warrant. Birmingham city offices are closing at noon because of the threat.

The National Weather Service says thunderstorms will develop ahead of an approaching storm system. They say tornadoes, damaging winds and hail as large as tennis balls are all possible.

___

7:15 a.m.

Twenty-nine million people faced a threat of severe storms Monday that could bring damaging hail, high wind and even tornadoes to the southeastern United States.

The national Storm Prediction Center said large parts of Alabama, Georgia and Tennessee and a small portion of northeast Mississippi would be under a tornado threat Monday afternoon and Monday evening. Forecasters said enhanced risk of severe storms covers Nashville and Chattanooga in Tennessee; and Birmingham, Huntsville and Tuscaloosa in Alabama.

In Alabama, tornadoes, hail the size of tennis balls and 70 mph (110 kph) winds were most likely to occur in parts of central and northern Alabama, including all of metro Birmingham.

In Georgia, the highest risk of tornadoes will be in northwest Georgia, including Dalton, Rome and Cartersville.