Click here for a list of county Cool Zones open to the public over the holiday weekend.
A heat wave expected to take hold of the region on Friday will swing temperatures from below average to above average in time for the Labor Day weekend.
"We head into the weekend, we [will] have an excessive heat watch for most of the county for your entire Labor Day weekend, so just in time right," NBC 7 Meteorologist Sheena Parveen said.
The National Weather Service issued an excessive heat warning that will be in effect from Friday morning through Monday evening for western valleys, the mountains and the deserts. An excessive heat watch will also be in effect from Saturday morning through Monday evening in coastal areas.
Temperatures will stay unseasonably cool through Thursday Parveen said. High pressure will strengthen over California throughout the week and begin ushering in the sweltering conditions on Friday, forecasters said.
"By the end of the week, we're going to start to see temperatures warming up. Then the weekend, it's going to be really hot around here especially for the inland valleys," Parveen said. "If you're inland, you're probably going to want to run that A/C this weekend."
Temperatures in the deserts could reach 119 on Sunday and Monday, while highs in the western valleys are expected to top out at 102 on Saturday, forecasters said.
No monsoonal moisture is expected to accompany this stretch of heat, meaning it will not feel as muggy as recent heat waves.
A Red Flag Warning was issued for Saturday and Sunday due to dry, gusty offshore winds with relatively low humidity, according to meteorologist Dagmar Midcap.
The county will have a long list of cool zones open to the public over the holiday weekend. Click here to see the full list.
The California Independent System Operator (CAISO) issued a statewide Flex Alert between 3 and 9 p.m. from Saturday to Monday due to increased demand on the electrical grid. Last month, strain on the grid amid a gripping heatwave forced the CAISO to activate rolling blackouts in communities across the state.