The month of July began with a dire warning: A rare, long-duration heat event was forecast to bring extreme heat risk across the West, with triple-digit temperatures and dangerous fire conditions expected across much of California for days at a time.
That outlook quickly proved correct and would end up defining much of the month in the Golden State, which would see little relief from the relentless heat.
On July 2, as the first heat wave began, utility officials initiated the first planned power outages of the year in some Northern California counties, trying to prevent dangerous fires in the scorching weather.
Then, records were broken across the state. Palm Springs experienced its hottest day ever, at 124 degrees on July 5. Redding hit an all-time high of 119 degrees on July 6. Palmdale and Lancaster had nearly a straight week of days with temperatures at or above 110 degrees, more than double the cities’ previous streaks.
Tragic results also began to pile up. Several wildfires sparked by extreme heat destroyed homes and forced families to flee. A motorcyclist died while touring Death Valley.
Without much relief, a second heat wave swept across the state’s interior. While not as intense or as long-lasting as the first, it still fueled the explosive growth of the Park Fire in Butte and Tehama counties. Within days, the blaze would become one of the largest wildfires in California history.
It was a historic month of extreme heat, and now climate data has confirmed just how unprecedented it was: July 2024 was officially the hottest month on record in California.
The average July temperature across the Golden State was 81.7 degrees, beating the previous record for July 2021 by nearly two degrees, according to data released Thursday by the National Centers for Environmental Information, a division of NOAA. The agency’s state climate data dates back to 1895.
“The July heat was notable not only for its sheer intensity … but also for its duration,” Daniel Swain, a climate scientist at UCLA, wrote in a blog post anticipating Thursday’s data release. “Temperatures remained extremely high for weeks and did not drop substantially at night, especially in the foothill thermal belts.”
Meteorologists and climate scientists said the record is not necessarily a surprise but is part of a path of dangerous global warming driven by human-caused climate change.
Of the hottest months on record in California, the top three have occurred in the past seven years.
Globally, July also saw two of the hottest days on record, with an average surface temperature of 17.15 degrees Celsius, or 62.87 degrees Fahrenheit, on both July 22 and 23, according to the European Union's Copernicus Climate Change Service.
Interestingly, for the first time in 13 months, global temperatures did not set a new record for the respective month, as the average July temperature was about 0.04 degrees Celsius behind the record for July 2023. However, July 2024 became the second warmest month globally on record.
“The streak of record months has come to an end, but only just,” said Samantha Burgess, Deputy Director of the Copernicus Climate Change Service, in a statement. “The bigger picture has not changed – our climate continues to warm. The devastating effects of climate change began well before 2023 and will continue until global greenhouse gas emissions reach net zero.”
By mid-year, global temperatures would have to fall dramatically to avoid once again becoming the warmest year on record, the climate agency said.
In California and the West, NOAA officials warned that the region is likely to see above-average temperatures again in August, with “significant potential for wildfires,” according to the agency's climate report released Thursday.
It remains to be seen whether August can rival the prolonged heat wave in early July, which was a major factor in breaking California's monthly heat records, as well as several other records across the state.
“We’ve had heat waves before that lasted maybe a week or so, but this one was very persistent,” said Andrew Gorelow, a meteorologist with the National Weather Service in Las Vegas, which provides forecasts for much of southeastern California.
Death Valley, the national park known for its sweltering temperatures, also recorded its hottest month ever, with average highs of 121.9 degrees, according to park officials. Temperatures reached at least 120 degrees on all but seven days of the month, with the hottest day, July 7, hitting 129 degrees.
“Six of the 10 hottest summers on record have occurred in the past 10 years, which should serve as a wake-up call,” Mike Reynolds, superintendent of Death Valley National Park, said in a statement. “Record-breaking months like this could become the norm as we continue to see global temperatures rise.”
The historic month saw a variety of new records across California:
- In Los Angeles County, both Lancaster and Palmdale set a record for most consecutive days with temperatures above 100 degrees: 25 in a row, from July 2 to 26, surpassing the previous record of 23 days, according to the National Weather Service.
- July was also the warmest month on record in Lancaster and Palmdale. Lancaster had an average high temperature of 104.9 degrees, 2 degrees higher than the record set in August 2022. The average July temperature in Palmdale was 105.4 degrees, also 2 degrees higher than the record set in July 1961.
- Sanberg, in the mountains of Los Angeles County, recorded its hottest month on record, with an average monthly temperature of 93.5 degrees. The previous record was 92.5 degrees, recorded in July 2021.
- Palm Springs, which had its hottest day on record, also had its hottest month, with an average high temperature of 114.9 degrees, surpassing the record set last July.
- In the Central Valley, Merced, Madera, Fresno and Bakersfield also recorded their hottest month in recorded history, with average temperatures breaking records set between 1931 and 2021, according to the National Weather Service.
- Several regions in the Sacramento Valley, including Red Bluff, Redding and Modesto, experienced their hottest July on record this year, according to the National Weather Service.
Times staff writer Hayley Smith contributed to this report.
