Hot to Get Hotter on Sunday, Labor Day

Forecasters say the weather will get dramatically hotter this Labor Day weekend, with high temperatures of 105 or more in the San Fernando and San Gabriel valleys on Sunday and Monday.

During the last couple of weeks, temperatures remained at or below normal in the Los Angeles Basin, thanks largely to a persistent onshore flow of cool, moist air from the Pacific.

But the National Weather Service says that onshore flow should end this morning, with coastal clouds clearing away by noon. Beachfront thermometer readings in the 70s are expected by midafternoon, with top readings of close to 100 in the valleys.

Temperatures about 5 degrees higher than Saturday’s are expected on Sunday and Labor Day, with only slight cooling Tuesday. But forecasters said a return of the onshore flow could drop temperatures below normal again toward the end of next week.