Extreme heat greets September in Southern California

Southern California health officials warned the public to take precautions against heat-related illnesses as triple-digit temperatures were expected this week throughout the region.

The National Weather Service issued an excessive heat warning from 11 a.m. Tuesday to at least 8 p.m. Friday in the western San Fernando Valley, and 11 a.m. Wednesday to at least 8 p.m. Friday for most other parts of Los Angeles County.

Downtown LA could reach 98 degrees on Thursday and 99 on Friday, and the hottest Valley temperature of 110 was forecast for Wednesday-Friday in Woodland Hills, according to the NWS.

Van Nuys, Burbank and Pasadena hit 99 on Monday with a forecast in the low 100s for the remainder of the week.

West Hollywood saw a high of 88 Monday, with 96 expected Thursday and Friday.

Nighttime temperatures were expected in the 70s in the valleys into the weekend.

In Orange County, Anaheim reached 89 on Monday and could climb to 96 Wednesday, 98 Thursday and 97 Friday. Irvine was forecast to hit 96 on Thursday and 95 on Friday.

The beaches will not have extreme heat. Santa Monica was 79 on Monday, but forecasters said it could climb to 85 on Thursday. Huntington Beach’s high was expected to be 80 Thursday and Friday.

A less severe heat advisory was issued for LA beaches, Palos Verdes Hills and the Malibu coast for temperatures that could reach 90 degrees from 11 a.m. Thursday to
8 p.m. Friday.

The LA County Department of Public Health advised the region’s residents and visitors to drink a lot of fluids, stay in an air-conditioned room, avoid direct sunlight and check on relatives and neighbors, especially seniors, young children and people with medical conditions.

Residents were also cautioned to never leave children or animals in unattended vehicles, which reach deadly temperatures in just a few minutes.

The hot, dry weather also creates a higher risk of fires this week in Southern California mountains, valleys and deserts, officials warned.

“Although it’s crucial that we take care of ourselves, it’s equally important that we extend our hand to those in need,” LA County Health Officer Muntu Davis said in a statement. “We must look out for those who are more likely to get ill due to the heat, including the elderly, unwell, pregnant women, children, and those living alone. Hot days aren’t just uncomfortable — they can be dangerous. However, if we make sure to stay hydrated and keep cool, we can protect ourselves and our loved ones, friends, and neighbors. If you have an elderly or unwell family member or neighbor, check on them regularly to ensure they are safe and well.” 

Inland Empire

Temperatures were expected to be around 110 degrees throughout the week in the hottest areas of Riverside County, forecasters said Tuesday.

The Inland Empire — which includes the valley areas of San Bernardino and Riverside counties and the cities of Ontario, Rancho Cucamonga, Corona, Riverside, Moreno Valley, Fontana and San Bernardino — was under an excessive heat warning from 11 a.m. Wednesday to at least 8 p.m. Friday, according to NWS.

“Dangerously hot conditions with high temperatures of 102 to 112 expected,” the NWS reported. “Warmer nights with low temperatures mostly in the 70s, warmest near the foothills of the mountains.”

The NWS posted on social media that temperatures 10 to 15 degrees higher than average were likely.

The heat wave will also elevate the chance of fire across the mountains, valleys and deserts this week.

Monday’s high for the Labor Day holiday in Palm Springs was 110 degrees, and the NWS predicted that would increase to 113 on Wednesday and 116 Thursday.

Coachella hit 109 Monday, with 112 expected on Wednesday and 115 Thursday.

In downtown Riverside, the thermometer struck 100 on Monday, and was expected to rise gradually throughout the following days, peaking at 107 Thursday and 106 Friday.

A similar pattern was forecast for Hemet.

Nighttime lows were expected to be in the upper 80s in the hottest areas.

The city of San Bernardino reached 104 Tuesday, and the high in Ontario was 98. Overnight lows were expected in the low 70s.

Cooling centers in Palm Springs are at Demuth Community Center, James O. Jessie Desert Highland Unity Center and the Palm Springs Public Library through the end of the month. More information is at EngagePalmSprings.com.

The San Bernardino County Public Health Department provides a website that includes information on places to cool off in the county and how to identify symptoms of heat-related illness. A list of community centers, libraries and other air-conditioned locations is also available on the county’s website.

San Diego County

An NWS excessive heat warning was also in effect for Wednesday at 11 a.m. to at least 8 p.m. Friday for inland valley areas of San Diego County.

The cities of San Marcos, Escondido, La Mesa, Poway, Santee, and El Cajon could experience “dangerously hot conditions” with highs of 102 to 110.

Updated Sept. 3, 2024, 2:59 p.m.

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