One More day to Swelter, Then the Rain Comes

The Southland will swelter under abnormally high temperatures for one more day today and a low-pressure system combined with a plume of sub-tropical moisture will bring showers and possibly thunderstorms starting tonight, perhaps lasting through Tuesday night, forecasters said.

“If thunderstorms develop, some potential impacts will include urban roadway flooding, localized flash flooding in the mountains and desert, a threat of debris flows in recent burn areas, and dangerous lightning along the beaches,” said a National Weather Service statement. “Showers and thunderstorms will also be possible over the coastal waters and Catalina Island.”

As of early this morning, the forecast called for no precipitation in Los Angeles County during daytime hours today but a 30 percent chance of showers and thunderstorms tonight -- 60 percent in Orange County, said NWS meteorologist Andrew Rorke.

The NWS also said there is a “slight chance” of showers and thunderstorms in Orange County this morning, and a chance of the same in the afternoon. The chance of measurable precipitation in Orange County was set at 40 percent today, rising tonight and falling to 20 percent Tuesday night.

Humidity levels will be normal today -- around 40 percent in coastal areas, the teens in the desert -- meaning the weather will not feel particularly muggy, Rorke said.

Temperatures, meanwhile, were expected to be high once again, reaching the 90s in several communities. Declines of between seven and 10 degrees were expected in those areas Tuesday, when temperatures will be at normal levels again.

The NWS forecast sunny skies in L.A. County today but partly cloudy skies in Orange County and highs of 81 in San Clemente; 83 in Newport Beach; 84 in Avalon; 85 at LAX and in Laguna Beach; 88 on Mount Wilson; 89 in Irvine and Mission Viejo; 90 in Anaheim; 92 in Fullerton; 93 in Long Beach and San Gabriel; 94 in downtown L.A., Pasadena and Yorba Linda; 95 in Burbank; 96 in Woodland Hills and Saugus; and 97 in Palmdale and Lancaster.

City News Service