When is heat wave coming, and how long will it last?

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LOS ANGELES — A heat wave is about to wash over the Southland and send temperatures into triple-digit territory amid an elevated danger of wildfire, the National Weather Service said Tuesday, issuing an excessive heat watch from Friday morning through Saturday evening.
The heat watch will be in effect along the Central Coast, in Ventura County, in Orange County and in all of L.A. County, including beach cities, metropolitan L.A., the downtown area and the Hollywoo