A “significant warming trend” began in Southern California Monday, generating triple-digit temperatures in Los Angeles County valleys and record-setting heat in Lancaster.
The National Weather Service attributed the warming trend to an upper- level high-pressure system strengthening over Northern California and Nevada combined with “a weak northerly wind component at the lower levels.”
“Widespread triple-digit heat is expected across the lower mountains, Antelope Valley and interior valleys,” according to the NWS.
By Tuesday, an increase in monsoonal moisture will potentially lower temperatures a few degrees across Los Angeles and Ventura counties, but the increased humidity “will lead to significant discomfort,” forecasters.
An excessive heat warning issued by the NWS will be in effect until 10 p.m. in the Antelope Valley. A slightly less serious heat advisory will be in effect until 10 p.m. Tuesday in the Santa Clarita Valley and Los Angeles County mountains, excluding the Santa Monica range.
Forecasters urged people who work outdoors to save strenuous activities for the early morning or evening, wear light-colored, loose-fitting clothing, and drink plenty of water.
The temperature reached 109 degrees in Lancaster Monday, beating the record of 107 set for the date in 1951.
Above all, they said, be aware that “temperatures inside vehicles, even if the windows are partially open, can quickly rise to life-threatening levels. Never, ever leave people or pets in enclosed vehicles, even for a short period of time.”
Temperatures will stay the same in some communities Tuesday, climb in others by up to 4 degrees and decline by a few degrees in some areas, including Lancaster, where a high temperature record for a July 30 was matched Sunday, when temperatures reached 106 degrees, the same as in 2000.
Meanwhile, a beach hazards statement, which is a notch less serious than a high surf warning, is in effect along the Los Angeles County and Orange County coasts until Tuesday night.
The statement was issued in response to a long-period southerly swell generating higher-than-normal surf along south-facing beaches, along with strong rip and longshore currents.
“There is an increased risk for ocean drowning,” according to the NWS. “Rip currents can pull swimmers and surfers out to sea. Large breaking waves can wash people off beaches and rocks and capsize small boats near shore.”
Surf is expected to average 3-6 feet, forecasters said, with local sets of 7 feet possible.
—City News Service