It will be another warm day with temperatures in the 80s and partly cloudy skies, the National Weather Service said.
Showers and scattered storms will develop late Monday afternoon and continue at times through the evening ahead of the front.
Some areas could see gusty winds, drenching downpours, and local flooding during that time.
For a projected radar image of the region simulated for 6 p.m. Monday from the National Weather Service, see the image above.
After patchy morning fog, it will clear out on Tuesday, Sept. 20, which will be mostly sunny and pleasant with a high temperature of around 80 degrees.
Look for more of the same on the last full day of summer on Wednesday, Sept. 21, with plenty of sun and a high temperature again around 80.
Another cold front will lead to a new round of showers after nightfall on Wednesday, continuing at times into the overnight hours, with some parts of the region getting around a quarter-inch of rainfall.
Thursday, Sept. 22 will start off with scattered morning showers before becoming partly sunny with a high temperature in the low 70s.
The fall equinox arrives at 9:04 p.m. Thursday in the Northern Hemisphere.
The first full day of fall on Friday, Sept. 23, almost on cue, will be noticeably cooler with a high temperature in the low 60s and mostly sunny skies.
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