MONTEREY (CBS SF) -- The National Weather Service has issued an excessive heat watch for most of the San Francisco Bay Area for Tuesday and Wednesday, with temperatures in the big cities of particular concern, a meteorologist said Sunday.
Warm temperatures from today to Monday will turn to really hot on Tuesday and Wednesday, with degrees in the mid-80s to 90s near the coast and mid-90s to 103 inland, according to Ryan Walbrun, senior meteorologist for the weather service in Monterey.
The high heat conditions will come from a ridge of high pressure with easterly and northeasterly winds blowing hot air towards the Bay Area from the Nevada desert and only light cooling winds from the ocean, Walburn said.
"Think of it as a big warm area coming over the region," Walburn said.
The excessive heat watch will start at 1 p.m. on Tuesday and continue to 8 p.m. Wednesday, according to Walburn.
The two-day heat warning will be of biggest concern in San Francisco, Oakland and San Jose that are densely populated and not many people have air conditioning to cool off with, he said.
A lot of residents are just not used to handling such hot weather and heat lingering in their homes for 24 to 48 hours in May, Walburn said.
"It's the sudden change from 60 to 65 degrees to 95," he said. "It can be somewhat hard for someone who is elderly to deal with that."
The heat wave will subside some on Thursday, which will still be a warm day, with highs that might be in the 90s in the East Bay.
On Friday, the Bay Area should see a return to temperatures in the 70s and 80s, which are seasonable for this time of year, Walburn said.
The weather service's excessive heat watch does not include the coastlines of Sonoma, Marin and San Mateo counties and interior portions of Monterey and San Benito counties, he said.
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