san diego weather

San Diego Weather: The Start of Fall Feels More Like Summer

According to NBC 7's First Alert Forecast, the hottest day of the week will be Wednesday, which also happens to be the first day of fall 2021

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San Diego, you may want to leave those fall sweaters tucked away a little bit longer. The final day of summer brought serious heat to San Diego County and that is going to linger into the first day of fall. Here's what you can expect.

The National Weather Service in San Diego has issued a heat advisory for San Diego’s inland valleys and foothills that will be in effect Wednesday from 10 a.m. through 8 p.m. During that time, temperatures are expected to climb between 93 and 98 degrees.

NBC 7’s Brooke Martell said temps began trending upward Tuesday. By the time the heat advisory kicks into gear, it’s going to feel like summer never ended.

She said Wednesday – as in the first day of fall – will be the warmest day of this warm-up.

NBC 7 meteorologist Dagmar Midcap said San Diego County could likely see some record highs broken or tied on Wednesday.

On Tuesday, the National Weather Service said record highs were tied in two San Diego-area communities: Ramona, which hit 101 degrees and tied the record high set back in 1975, and Vista, which hit 92 degrees, tying a record high set in 1992.

As always during hot weather conditions, the NWS said people should drink plenty of water, avoid strenuous activities, and limit their time spent outside. We’ve got some heat safety tips here or below:

Oof, it is HOT out there, San Diego. NBC 7 meteorologist Sheena Parveen shares safety tips on how to beat the heat during these heat waves in San Diego County.
NBC 7 Meteorologist Dagmar Midcap has your evening forecast for Sept. 20, 2021.

Weak Santa Ana Winds

San Diego’s inland areas aren’t the only parts of the county feeling the heat during the start of fall. Martell said that as high pressure continues to build, temps will climb across the county.

“Weak Santa Ana winds across the mountains and deserts will also contribute to the warm forecast, keeping most daytime highs above average,” she explained.

NBC 7 Meteorologist Crystal Eggers explains the phenomenon behind Santa Ana Winds when they roll through San Diego County.

But Will It Actually Feel Like Fall in San Diego Any Time This Week?

So, we know San Diego knows summer all too well but is there a chance of those fall-like conditions in our region at all this week?

Yes, at least by SoCal standards.

Martell said the high-pressure system will start to break down and shift east after Wednesday and a low-pressure trough will bring milder temps – a “return to seasonal norms,” at least – through the weekend.

"A cooling trend will carry all the way through the weekend for much more seasonable temps," Midcap added.

By about mid-next week, there’s a chance of thunderstorms over San Diego’s mountains.

Have you ever wondered how and why we sweat? After a ride on her beach cruiser, NBC 7 and Telemundo 20 meteorologist Ana Cristina Sanchez explains the science behind what's happening to our bodies when we sweat.
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