Posted September 22, 2018 4:17 p.m. EDT
Rain and thunderstorms will be most notable Sunday, from East Texas and Louisiana up through Arkansas into portions of Tennessee and Kentucky. Highs will be in the lower to middle 70s, while much of the Deep South will reach well into the 80s to near 90.
The first full day of autumn will be cool across the Northeast with sunshine. Under a moonlit sky, temperatures will drop to frosty levels from the Adirondacks eastward to interior Maine. Farther south across the Mid-Atlantic, clouds will help keep temperatures in the 60s, with a bit of rain at times across Maryland and Virginia.
A low pressure system is expected to form over Wyoming and South Dakota and few showers will develop across parts of Montana and North Dakota. In contrast, south of the storm will be rather sunny and much warmer as temperatures soar into the 80s over the eastern Rockies and western Plains.
The Northwest will remain relatively cool but mainly dry with some sunshine. Farther south, sunshine will keep it hot and dry across the interior valleys of California and the Southwest deserts.
FOCUS: Fire Danger Out West
Gusty winds sweeping through the interior West will enhance the risk of wildfire ignition and spread Sunday. The fire risk will be greatest from northeastern California through Nevada, Utah and Wyoming. The wildfire danger will lessen early this week as winds diminish.