LOS ANGELES (CBSLA) — Wednesday will mark the warmest day of the week as temperatures reach the low 100s in areas of L.A. County and the 90s in Orange County, the National Weather Service said.

High pressure will bring temperatures from 93 to 103 to the valleys, 80 to 100 in the mountains and foothills, and 85 to 93 along the coast, according to the weather service.

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Temperatures Woodland Hills will be the highest of Wednesday’s heatwave as they reach 101, seven degrees hotter than the day prior. Other areas reaching high temperatures include Lancaster with 100 compared to 95 the day before; 98 in Saugus, up 7 degrees; and 97 in Pasadena, compared to 89 Tuesday.

A cooldown is expected to begin Thursday.

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Forecasters urged area residents to limit outdoor activity during the hottest part of the day and to drink plenty of fluids.

Residents are also reminded to never leave children, seniors, or pets in hot parked cars.

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(© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)