What weather forecasters say will be a four-day heat wave begins Tuesday, with rising temperatures accompanied by high winds and low humidity that could cause red-flag conditions across Southern California.

The Los Angeles area is expected to see a 20-degree warm-up compared with Monday, with temperatures in the mid-90s inland, according to the National Weather Service. At the beaches, temperatures are expected to hit the mid-80s.

Winds of between 20 and 30 mph -- with afternoon gusts of up to 45 mph in some mountain passes and canyons -- combined with low humidity levels could create dangerous fire conditions, forecasters warned.

The heat wave is expected to last through Friday, peaking on Wednesday with temperatures up to 100 degrees possible in some valley areas. There will be little relief at the beaches, with daytime temperatures expected to peak near 90 degrees Wednesday, the weather service said.


The unseasonably warm weather will ease only slightly Thursday and Friday before Saturday brings “significant cooling” to the region, forecasters said.

Until then, forecasters predicted that multiple high-temperature records would fall this week, particularly on Wednesday.

jason.wells@latimes.com

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