Temperatures along the coast and in the western valleys will be somewhat cooler, but still 5 to 10 degrees above average, according to the weather service. Additionally, a heat advisory is in effect for the Pomona area, San Fernando Valley and Santa Clarita Valley from Monday to Tuesday, and for the San Gabriel Valley for Tuesday.
High temperatures in San Diego County's deserts are predicted to be 107 to 112 degrees Friday, 109 to 114 degrees Saturday, 111 to 116 degrees Sunday, 113 to 118 degrees Monday, 115 to 120 degrees Tuesday and 114 to 119 degrees Wednesday.
"There is absolutely no doubt we will be near all-time highs with this heat wave, with the hottest and most risky temperatures expected Monday through Wednesday", the National Weather Service in Phoenix said, offering heat safety tips.
NWS forecasters stated a dome of exceptionally hot and dry air had made its way into the region on Thursday, resulting with the 2017 calendar year high temperature - thus far - of 104 degrees, according to weather data observed by the Seminole Sentinel via Texas Tech University's weather mesonet monitoring system.
Officials urged people to stay hydrated, and residents said they'd be drinking lots of water and splashing in pools.
"Take proper heat precautions if you are planning outdoor activities", meteorologists state.
Notorious hot spot Death Valley, home to the world's all-time hottest temperature of 134 degrees, will soar to 123 degrees by Sunday.
Nighttime temperatures are expected to be around 60 degrees.
As hot as it's expected to be, Pi said he does not believe any heat records to fall over the next five or so days.
"While it is very important that everyone take special care of themselves, it is equally important that we reach out to those who are especially vulnerable to the harmful effects of extreme heat, including children, the elderly, and their pets", Gunzenhauser said.