Hot, dry weekend on tap for Southern California as ‘heat dome’ makes its way across the Midwest

Another warm weekend is looming in Southern California as a high pressure system makes its way over the region, causing  temperatures to slowly climb — with some inland cities expected to reach triple-digit heat by Saturday.

The high-pressure system, known as a heat dome, was making its way across the Midwest this week, and was expected to be hovering over Texas into the weekend, said National Weather Service meteorologist Mark Moede. While the borders of the dome are unclear it could potentially reach into the region, raising temperatures in the Inland Empire and parts of Orange County.

In the Inland Empire, temperatures were expected to be among the hottest in the region with some areas nearly 10 degrees higher than average.

Riverside County cities including Moreno Valley and Jurupa Valley were expected to be in the high 80s by Thursday, and reach into the mid to upper 90s by Saturday, Moede said. A slight cooldown was possible on Sunday.

Fontana, Colton and other San Bernardino County cities had already reached into the high 80s on Wednesday, and will continue to climb up into the high 90s, with some possibility for triple digit temperatures.

The wind-driven wildfire in Hesperia had reached 95 percent on Wednesday, stalling at about 1,078 acres. Winds were expected to remain around 20 mph over the weekend, Moede said.

Highs in Woodlands Hills, Monrovia and other inland Los Angeles County cities are likely to climb into the mid 80s by Thursday, June 20. By Saturday, the county’s hottest temperatures are expected to range in the low to mid 90s by Saturday, said NWS meteorologist Lisa Phillips.

The temperatures aren’t expected to change much on Sunday, though there is a chance for Woodland Hills to hit triple digits, Phillips said.

In the Gorman area north of Los Angeles, where firefighters were still working to contain the massive Post fire on Wednesday, temperatures in the high 70s on Thursday were expected to climb up to the low 90s by Saturday. Containment had reached 39% as of Wednesday morning.

The hotter, drier air could pose potential risks for additional wildfires — especially after a winter season with above average rainfall, Moede said.

“Now with the lack of rain, all the grasses and small saplings are going to add fuel to whatever fire may start,” Moede said.

Cities along the coast including San Pedro and Redondo Beach aren’t likely to feel the heat, with highs clinging to the low 70s through Sunday.

Further south to Orange County, cities like Newport Beach and Huntington Beach could be slightly warmer in the low 70s on Thursday, climbing into the mid 70s over the weekend, Moede said.

Anaheim, Fullerton and other inland cities are likely to see much hotter temperatures, from low 80s on Thursday in the high 80s by Saturday.

Not much change is expected heading into next week, with warm temperatures continuing to linger as the system moves away from the area.