Los Angeles extreme heat wave expected to last at least a week

Southern California is baking under an intense, week-long heat wave that has pushed temperatures up to 20 degrees above normal and triggered extreme heat warnings across the Los Angeles region.

The extreme heat warning took effect on Friday morning and is scheduled to run until at least Thursday evening, according to the National Weather Service. Forecasters warn that the stifling conditions could linger even longer, potentially stretching into the following weekend.

A powerful high-pressure system sitting over the eastern Pacific and the West Coast is driving the heatwave. It is bringing typical mid-summer conditions to a region that would normally expect pleasant autumn weather.

How hot will it get in Southern California?

The heat is expected to peak over the weekend, with inland valleys and the Inland Empire bearing the brunt of the triple-digit temperatures.

In downtown Los Angeles, where average October highs usually hover between 75 and 80 degrees, temperatures are forecast to spike to between 99 and 103 degrees. The surrounding valleys could see highs between 102 and 107 degrees.

Coastal regions from Santa Barbara down to Los Angeles will offer only mild relief, with highs forecast between 90 and 98 degrees. Further south, Orange County's inland valleys are bracing for temperatures as high as 108 degrees. Overnights will offer little respite, with temperatures remaining high.

"A long-duration heat wave is going to be in effect," NBC4 meteorologist Shanna Mendiola said, warning residents that the hot spell could last well into the second week of October and potentially break daily records.

Dodgers game and wildfire risks

The extreme weather will collide with one of the city's biggest sporting events of the year. On Saturday, the Los Angeles Dodgers are set to host the Atlanta Braves for Game 1 of the National League Division Series. Fans and players at Dodger Stadium can expect on-field temperatures to hover around 95 degrees.

The prolonged dry spell is also raising immediate safety concerns. Because humidity levels are expected to remain exceptionally low, the risk of wildfires is heavily elevated across Southern California.

Public health officials have urged people to stay hydrated, avoid outdoor exercise during the middle of the day, check on vulnerable neighbours, and ensure pets have adequate shade and water.

The region is also facing high surf. While the heat keeps people inland, a swell generated by Hurricane Rachel is expected to bring waves of five to six feet to local beaches between Tuesday and Thursday. The National Weather Service warned this could worsen the severe erosion that has plagued popular Southern California beaches all summer.

Forecasters say there is some relief on the horizon. Tropical moisture is expected to drift into the region by next weekend, which should help lower temperatures.