LOS ANGELES (CNS) -- Saturday is expected to be the hottest day of a protracted heat wave that is expected to linger into early next week, with many areas seeing temperatures that are four to eight degrees warmer than Friday, pushing into the triple digits in most valley and desert neighborhoods.
"The lower valleys will see highs from 98 to 106 and the lower mountain elevations and far interior sections will sizzle with highs between 104 and 113 degrees," according to the National Weather Service.
The coast will be a popular destination throughout the weekend, with temperatures hovering in the 70s and low 80s, forecasters said.
The heat wave has the Southland flirting with temperature records. On Friday, high temperatures "ranged from around 90 for the interior coastal areas to around 100-103 for the valleys, topping out at 105-109 for the desert," according to the NWS. "No new records were set."
But that could change Saturday as the high-pressure system continues to drive up temperatures, with the heat expected to persist through Monday. Excessive heat warnings and advisories that were in place for most areas through Monday morning have been extended until late Monday night.
In the Santa Clarita Valley, the 5 and 14 freeway corridors and the San Gabriel Mountains, an excessive heat warning issued Friday will remain in place until 11 p.m. Monday.
Forecasters said that area could see temperatures of up to 108 degrees, dipping at night only into the 70s and lower 80s.
In the Antelope Valley and accompanying foothills, an excessive heat warning will also be in effect through 11 p.m. Monday, with temperatures possibly peaking at 114 degrees and overnight lows dropping only into the 70s and 80s, according to the NWS.
The San Fernando and San Gabriel valleys and the Santa Monica Mountains Recreational Area will be under a less severe heat advisory until 11 p.m. Monday, with temperatures up to 106 degrees possible, forecasters said.
In Orange County, an excessive heat warning will be in effect until 8 p.m. Tuesday, with temperatures expected as high as 104 degrees.
"Extreme heat will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities," NWS forecasters warned. "Drink plenty of fluids, stay in an air- conditioned room, stay out of the sun, and check up on relatives and neighbors. Young children and pets should never be left unattended in vehicles under any circumstances."
The high heat is expected to contribute to "elevated to brief critical fire conditions" in desert, mountain and interior valley areas. Those areas will see humidity levels in the 5% to 15% range. Winds are expected to be relatively light, but some higher gusts are possible in traditionally wind- prone areas.
Elevated temperatures are likely to continue into next week, although more onshore flow is expected, helping to cool things off in the valleys. But mountains and interior areas "will likely continue to sizzle," forecasters said.
According to the NWS, Sunday is expected to be about 2 degrees cooler than Saturday, with another 2- to 5-degree drop anticipated on Monday.
The metropolitan Los Angeles area is not facing any heat advisories or warnings, but it will still be warm. Forecasters said the L.A. area in general will see temperatures around 90 during much of the heat wave, with coastal areas the place to be -- thanks to highs of about 80.