The season’s most dangerous heat wave is expected to bake Southern California and much of the American Southwest this week, with triple-digit highs and elevated fire conditions set to begin Wednesday and last for several days.
Extreme heat and fire weather advisories have been issued for much of inland Southern California, with peak temperatures expected Thursday and Friday. Downtown Los Angeles is forecast to reach 94 degrees, while Woodland Hills could hit 108. Los Angeles County valleys and the Inland Empire will likely heat up to 104 degrees. Palm Springs could hit above 113 and Death Valley is bracing for 120 degrees.
“This is going to be the most significant heat wave of the season so far,” said Ariel Cohen, the meteorologist in charge at the National Weather Service’s Oxnard office. “We’re going to be having a once-a-year, once-every-other-year-caliber heat wave. … Everyone needs to be getting prepared now.”
While this is typically the hottest time of year, he said, highs at the end of the week will reach near records, 10 to 20 degrees above normal. People need to stay hydrated, make sure they have access to air conditioning and refrain from outside activities in the heat of the day in order to avoid heat illness, Cohen said.
“The most impactful heat and fire weather concerns will pick up Wednesday through Sunday,” the weather service warned. “Consider reassessing outdoor plans for that time, stay hydrated, and be careful with anything that can spark a fire.”
An extreme heat watch has been issued for Wednesday through Saturday across the region, with highs up to 106 possible across the Los Angeles County valleys, the Ventura County valleys, the San Luis Obispo County valleys and mountains, the Santa Barbara County mountains and San Bernardino County deserts. The Riverside, San Bernardino and San Diego County mountains could see highs up to 99 degrees Thursday and Friday, while the Inland Empire is forecast to reach up to 104 degrees.
In and around Death Valley, where highs are expected up to 120 degrees, officials warn that “above normal daytime temperatures combined with minimal overnight relief from the heat” could increase the threat for heat-related illness.
The extreme heat watch stretches east across much of the desert Southwest, reaching into southwest Arizona and southern Nevada. Phoenix could see highs up to 114 degrees at the end of the week while Las Vegas is expected to reach up to 110.
The “several day heat event is coming … with a high risk for heat illness and fire danger,” the weather service’s daily forecast said.
With an already-parched landscape, Cohen said the heat and low humidity will compound ongoing fire concerns. Several fires ignited and rapidly grew last week during a less dramatic heat wave.
But this week’s higher temperatures will create exceptional fire weather, Cohen said, urging residents to have multiple avenues to receive emergency alerts and be ready to evacuate, if needed.
A fire weather watch, which signals that critical fire weather is expected, has been issued from Wednesday through Saturday for much of the Los Angeles and Ventura County mountains and foothills, warning that the “unseasonably hot and unstable air mass [is] capable of producing explosive fire behavior.”
“We’re expecting there to be very favorable conditions for fires to grow,” Cohen said. “The fires start to fuel themselves in this type of environment.”
