In July, California experienced its hottest month on record, with relentless heat affecting much of the American West for weeks. The state’s average temperature was 81.7°F (27.6°C), according to the National Centers for Environmental Information. However, some regions saw temperatures soar above 100°F (about 38°C). During an early July heatwave, several cities set new temperature records—Palm Springs reached 124°F on July 5, and Redding hit 119°F on July 6.
Death Valley, known for its extreme temperatures, recorded its hottest month ever in July, as reported by the National Park Service (NPS). In Nevada, Las Vegas reached a record 120°F on July 7, marking its hottest day ever and setting a new record for the number of days exceeding 115°F.
The effects of extreme heat are increasingly evident across the US and globally due to the climate crisis, which is driving more severe weather conditions. Last month, about a third of the US population was under heat warnings, and July 22 marked the hottest day ever recorded on Earth, surpassing the previous day’s record.
Extreme heat poses significant health risks and is the deadliest form of weather-related disaster, especially affecting the unhoused, seniors, and those without access to cooling facilities. The high temperatures in California also contributed to drying out vegetation and fueling wildfires. Late last month, the Park fire, ignited by an alleged arsonist who pushed a burning car into a ravine, quickly became the fourth-largest wildfire in the state’s history. The area had been exposed to temperatures of 100°F and higher for days before and after the fire started.
The Pacific Northwest has similarly faced severe heat and wildfires. Oregon has seen over 1.4 million acres (567,000 hectares) burned this year, the most in the past 32 years since record-keeping began. Intense heat contributes to more severe fires and challenging conditions for firefighters. Last month, firefighters battling the Thompson fire near the Park fire suffered heat-related injuries.
Heatwaves are becoming more frequent, intense, and prolonged due to climate change, according to Dr. Alexander Gershunov, a research meteorologist at the Scripps Institution of Oceanography. He described heatwaves as being significantly impacted by climate change, noting a trend toward more frequent and extreme heat events globally, with California being no exception.
