Triple-digit heat expected in LA County starting Friday

Some parts of Los Angeles County will see triple-digit heat beginning Friday and continuing into early next week, leading the National Weather Service to issue a heat advisory over the weekend. 

It will be in effect from 10 a.m. Saturday through 8 p.m. Sunday for the Santa Clarita, San Fernando and San Gabriel valleys, where forecasters said temperatures could reach as high as 101 degrees.

Experts said it is important to drink plenty of water and protect your skin from the heat. 

"One sunburn in your lifetime can double your chances of getting melanoma," said Dr. Anna Guanche, a dermatologist and founder of the Bella Skin Institute. "Melanoma is the most deadly type of skin cancer." 

She said the UV Index will determine how likely your chance of getting a sunburn during a heat wave can be. 

"If the UV Index is between 3 and 5, it could take 30-45 minutes to burn," she added. "If it is 11 or more the damage can occur in less than 10 minutes." 

An excessive heat watch will be in place from Saturday morning through Sunday evening in the San Gabriel Mountains, the Antelope Valley foothills and the 14 Freeway corridor.

According to the NWS, temperatures will trend upward each day into the weekend, with above-normal temperatures anticipated starting Friday, followed by the possibility of "dangerously hot conditions" over the weekend, "especially for the mountain areas and Antelope Valley."

Daytime high temperatures are expected to rise by 2 to 6 degrees Friday, pushing highs into the 100 to 105 range in the Antelope Valley, and the 80s and low 90s in the valleys.

The Los Angeles County Department of Public Health issued a heat advisory for the valley areas for Saturday and Sunday. 

Sunday will remain the same, but forecasters said the heat could drop off slightly, continuing into Monday.