NWS: Temps to Rise By Nearly 20 Degrees

A warming trend began Wednesday that, by Friday, will generate temperatures up to 20 degrees higher than normal—the result of high pressure building over the region, National Weather Service forecasters said.

"Persons planning to be outdoors this week should practice heat safety tips," urged an NWS advisory. "Keep your body hydrated with plenty of water and avoid strenuous activity during the hottest part of the day."

Forecasters said a broad area of high pressure will develop over the West Coast and Great Basin through the week, producing the warming trend.

"Daytime temperatures will rise 10 to nearly 20 degrees above seasonal normal in some locations by Friday," according to the advisory. "The hottest locations will be in the western San Fernando Valley, Santa Clarita Valley, and the Ventura County valleys..."

From the Central Coast to the Southland, temperatures will reach the century mark and feel even more oppressive because of the humidity, and an extreme heat watch may be issued later this week, according to the NWS.

The NWS forecast highs for the rest of the week in the mid-80s on the Palos Verdes Peninsula.

The beaches will be shrouded in patchy dense fog late at night and early in the mornings during the rest of the week and experience daytime highs in the 70s while the rest of the region swelters, according to the NWS.

Overnight lows also will be warmer than usual, in the high-60s, forecasters said, adding that, already, several record high lows have been set since Aug. 27

—City News Service, with additional reporting by editor Nicole Mooradian.