A Heat Advisory is in effect through Saturday for the valley, while a Excessive Heat Warning goes into effect Sunday through Tuesday.
Very hot temperatures can create a situation in which heat illnesses are possible.An Excessive Heat Warning means that a prolonged period of dangerously hot temperatures will occur.
It's about to get really hot in the Southwest, and health officials want people to stay alert.
The heat wave will kick off Friday, with the mercury climbing into the upper 80s in San Jose and into the mid 90s in Morgan Hill, Pi said.
Temperatures, especially across Riverside County, could potentially hit the 120-degree mark, mainly in the deserts. Highs of 92 to 102 degrees are expected over the weekend, and highs of 96 to 104 degrees are in the forecast Monday through Wednesday, according to the NWS.
The high for Monday will be 101, Tuesday's high is expected to be near 105 degrees and Wednesday is expected to reach 106 degrees. Pi encouraged Bay Area residents to drink plenty of water and to stay out of the heat as much as possible.
Authorities also warned against leaving children or pets in parked cars, which can heat up to lethal levels in just minutes.
"If you are exposed to high temperatures and humidity for too long you sweat heavily, and if you don't drink enough fluids, your body's cooling system may fail", according to the health department. Sadly, in homes in areas with high crime rates, some of the people found dead in their homes from the heat had nailed their windows shut to protect themselves and their property. Anyone overcome by heat should be moved to a cool and shaded location.