Southern California is set to experience a dangerous and prolonged heat wave beginning Friday, with temperatures projected to reach triple digits in some areas and extreme conditions expected to last through next week.
The National Weather Service (NWS) has issued an Extreme Heat Warning, effective from 10 a.m. Friday through 8 p.m. next Thursday. This warning applies to coastal and valley areas of Los Angeles County, as well as coastal and inland Orange County.
Forecasters indicated Friday will see temperatures 10 to 15 degrees above normal. Highs in most coastal areas of Los Angeles County could reach the mid-to-upper 80s, with parts of the coast hitting the lower to mid-90s. Valley temperatures are expected to range from the upper 90s to 105 degrees. For coastal Orange County, highs are anticipated to be in the mid-80s to around 90 near the shore, climbing to the lower to mid-90s near higher coastal terrain. Inland Orange County could see temperatures from the mid-90s to near 100 degrees.
Saturday is predicted to be the hottest day of the next seven, according to the NWS. Temperatures are expected to rise an additional 2 to 4 degrees in coastal and valley areas, with some localized increases of up to 6 degrees. This means most coastal areas could reach the 90s, while valley temperatures in Los Angeles County could soar to between 100 and 107 degrees, roughly 15 to 20 degrees above normal.
While the heat is expected to ease slightly on Sunday, temperatures are largely anticipated to remain 10 to 15 degrees above normal from Monday through Wednesday. Forecasters also noted that above-normal overnight temperatures will likely limit relief from the daytime heat. The NWS emphasized that while this event may not set new records, its prolonged duration makes it very dangerous. They warned that the “relentless heat will have a hazardous wearing down effect on people, (especially) the very young and old.” Long-range models suggest conditions might begin improving around October 10.
Adding to the week's weather, humidity is expected to increase between Monday and Wednesday as moisture from Hurricane Rachel moves into the region. The weather service projects a 5% to 15% chance of afternoon showers or thunderstorms in the mountains during this period.
In light of the impending heat, the Los Angeles County Department of Public Health has urged residents to take precautions. Dr. Muntu Davis, Los Angeles County Health Officer, highlighted that “Heat causes more deaths in the U.S. annually than floods, storms, and lightning combined.” He advised residents to stay hydrated, avoid outdoor activity during the hottest hours if possible, and utilize air-conditioned spaces or cooling centers if their homes cannot be kept cool.
Those most susceptible to heat-related illness include older adults, young children, outdoor workers, athletes, and individuals with chronic medical conditions, as well as pregnant people and those who live alone. County health officials urged residents to check on these at-risk individuals. They also provided guidance on recognizing heat stroke or heat exhaustion symptoms such as dizziness, nausea, rapid heartbeat, confusion, or passing out, advising immediate medical help in such cases.
For residents without access to air conditioning, cooling centers, splash pads, and community pools are available. Los Angeles County officials stated residents can call 211 to find nearby facilities. The City of Los Angeles Emergency Management Department echoed this, urging the use of public libraries, recreation facilities, and senior centers. City officials noted temperatures could reach 100 degrees in downtown Los Angeles, 90 degrees at the coast, and 105 degrees in the valleys. They also advised calling 311 or using the city’s Cool Spots LA online tool to locate cooling facilities.
Officials also offered advice for individuals who must work, exercise, or spend extended periods outdoors. They recommended rescheduling strenuous activities for the early morning or evening when feasible, wearing lightweight and loose-fitting clothing, and taking frequent breaks in shaded or air-conditioned areas. If someone experiences possible heat stroke, city officials advised moving them to a cool, shaded location and calling 911 immediately.
