San Diego County will begin fall without the sticky humidity forecasters expected

Fall will get off to a pleasant start Monday across San Diego County, largely because a subtropical system off Mexico that looked like it would grow and send lots of humid weather to the region turned out to have little punch.

It’s possible there will be scattered showers in the county’s eastern mountains. But the National Weather Service says the sun will break through in most areas. San Diego’s daytime high is expected to hit 77 on Monday, 78 on Tuesday, and 78 on Wednesday. The seasonal high is 77.

The county received significant rain last week from subtropical weather that developed south of Cabo San Lucas. It sent a blob of moisture north, producing high humidity locally, making many people uncomfortable.

Such moisture is still badly needed. San Diego International Airport has received only 5.06 inches of precipitation during the yearlong water year that began on Oct. 1, 2024. That’s 4.67 inches below average. The airport averages about 9.5 inches of precipitation during the water year.

The lack of rain has produced extreme drought conditions in the eastern half of the country and severe drought to the west, according to the U.S. Drought Monitor.