Forecast for Hot and Muggy Weather Over the Weekend

The typical fair July weather that has graced San Diego for the last week or so will give way to hot and muggy days by the weekend.

“The temperatures will be climbing every day, as well as the humidity,” National Weather Service forecaster Wilbur Shigehara said. “It will be fair Friday and Saturday, but by Sunday the clouds will have increased.”

Whether the clouds will increase enough to cause thunderstorms in the inland valleys is uncertain.

“There is a 30 to 40% possibility of thunderstorms in the desert and mountain regions by Sunday,” Shigehara said. “Whether those thunderstorms will make it into San Diego is a big question mark.”

The shifting of upper-level winds to a south-southeast direction is blamed for the change in the weather pattern. The high humidity and stormy conditions in northern Mexico will now be circulated into the Southland, and the high pressure currently in the Southeast United States will expand westward this weekend.

July temperatures so far have not deviated from the average by more than two or three degrees. The high temperature at Lindbergh Field Thursday was 75 degrees, while average for that date is 76. The low was 64, one degree below the average, 65.

Today’s high at Lindbergh Field is expected to reach 77. It will climb to 80 by Saturday and 82 by Sunday.

High temperatures at the beaches will be 75 today, 77 Saturday, and 78 by Sunday. Overnight lows will be near 62 degrees.

“It will be good beach weather, simply because it will be just too warm and too humid inland,” Shigehara said. “The coastal clouds will clear up quickly, especially Saturday and Sunday mornings.”

Ocean temperature will be 66 degrees, and the surf two to three feet.

Inland high temperatures should reach 90 today, 95 Saturday and 97 Sunday. Lows will range in the upper 50s and low 60s.

“There is a chance that the clouds could come in and knock down those temperatures,” Shigehara said. “This is especially true on Sunday.”

Mountain high temperatures will be around 80, with overnight lows near 55. Desert highs will range from 103 to 110 Friday and 100 to 107 Saturday and Sunday, a slight drop because of the increasing clouds.