On Friday, October 2nd, extreme high temperatures began to scorch Southern California, with multiple counties seeing temperatures above 90 to even 100 degrees Fahrenheit (37.8 degrees Celsius). Even cities near the coast found it hard to escape the heat. The National Weather Service has issued a heatwave warning for the greater Los Angeles area, with the high temperatures expected to persist until next Thursday.
On that Friday, high heat advisories were in effect for most of Los Angeles County, Ventura County, and Santa Barbara County. In the San Fernando Valley of Los Angeles, the Woodland Hills community near the mountains saw temperatures reaching as high as 104 and 106 degrees Fahrenheit (40 and 41.1 degrees Celsius) on Friday and Saturday.
While the coastal areas of Los Angeles are typically cool in the summer, during this heatwave, temperatures are expected to exceed 90 degrees Fahrenheit. In downtown Los Angeles, the daily high temperatures from Friday to next Thursday will range between 97 and 99 degrees Fahrenheit (36.1 to 37.2 degrees Celsius), reaching 100 degrees on Saturday; with nighttime lows of 74 to 78 degrees Fahrenheit (23.3 to 25.6 degrees Celsius).
Historical weather records show that the average high temperature in downtown Los Angeles for October is 80 degrees Fahrenheit (27 degrees Celsius), with the highest recorded temperature of 101 degrees Fahrenheit (38.3 degrees Celsius) dating back to 1971. The summer of 2022 also saw a record 10-day heatwave. In California’s “October heatwave” in 2024, record-breaking high temperatures were reported in many parts of the greater Los Angeles area.
AccuWeather meteorologist Lauren Hyde predicts that temperatures in many areas will be 10 to 15 degrees Fahrenheit above historical averages until later next week.
NBC meteorologist Sheena Parveen forecasts that the extreme heat may persist until next weekend, with the possibility of the heat advisory being extended. She stated that this could potentially be the longest and hottest period of extreme heat in many years.
Experts point out that the “heat dome” is one of the reasons for the formation of abnormally high temperatures. According to the American Meteorological Society, a heat dome occurs when a high-pressure system traps warm air below it, preventing it from rising and creating a dome-like effect.
Specifically, high pressure causes air to sink in the upper atmosphere, compressing the air below and rapidly warming it. The sinking air forms a large lid near the ground, preventing cloud formation and allowing uninterrupted sunlight to heat the surface, further warming the trapped high-pressure system.
John Abatzoglou, a climate science professor at the University of California, Merced, told the Los Angeles Times that even without the heat dome, Southern California would experience heatwaves due to offshore winds bringing high temperatures to areas south and west of the mountains this time of year.
Western Weather Bureau expert Daniel Swain said in a post on X that this long-lasting and intense heatwave is related to the western high-pressure ridge. The notable aspects of this heatwave are its duration and the extent of its impact.
Swain also believes that this heatwave will last for more than 10 days, with nights becoming warmer, potentially breaking records in many cases. Additionally, coastal areas will be more humid compared to the normal levels for the autumn heatwave season.
AccuWeather meteorologists remind that this prolonged heatwave with poor nighttime cooling effects could lead to more severe impacts, exacerbating various health issues. Outdoor workers and families lacking cooling facilities will be particularly affected; the high temperatures pose a threat to animals as well, with the scorching pavement possibly burning their paws.
According to the high heat warnings from Los Angeles County, extreme heat can sometimes be life-threatening. Officials state that all cooling centers in the region are equipped with air conditioning, restrooms, and drinking water and will be open to the public during specified times, with some locations possibly extending their hours.
Southern California Edison (SCE) power company warns that grid maintenance or upgrades may cause some communities to experience power outages. Residents can check the outage areas or planned outage times on the company’s website to be prepared. Currently, SCE is considering implementing public safety power shutoffs, with Riverside County potentially being the most affected, affecting up to 14,828 customers.
SCE advises customers to prepare for planned outages or emergencies by stocking up on essentials, communicating with family members, and practicing evacuation plans to ensure safety.