LOS ANGELES (CBSLA) — This week’s heat wave could bring triple-digit temperatures to Southern California Wednesday, prompting heat advisories and excessive heat warnings.

Highs could reach up to 20 degrees above average throughout the region.

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A heat advisory will be in effect starting at 10 a.m. Wednesday throughout Los Angeles, including in beach cities, downtown L.A., the Hollywood Hills, the Long Beach, the Santa Monica Mountain Recreational Area, the valleys, into the Inland Empire and Orange County.

Wednesday temperatures could hit between 85 and 90 degrees near the coasts, and between 90 and 100 inland and in the valleys. And the heat won’t let up at the end of the day — Thursday is forecast to get even hotter.

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“Hot temperatures could linger well into the evening and some areas may not drop below 70 degrees overnight,” according to the National Weather Service.

Strong winds are also expected to make things extra uncomfortable. A wind advisory is in effect until 9 a.m. Wednesday for the San Gabriel Mountains, where winds of 20 to 30 miles per hour are being forecast, along with gusts of 50 mph.

People were encouraged to exercise in the early morning or in the evening, wear lightweight or loose-fitting clothes, and take frequent rest breaks in the shade or in air-conditioned indoor areas while working outside.

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Cooling centers are opening in Los Angeles County to provide a refuge for anyone without air conditioning.