This week, an early-season heatwave has shattered multiple temperature records in California and Arizona, hitting unprecedented highs on Wednesday and Thursday.

Summer-like weather conditions are anticipated to persist and extend towards the eastern regions.

Currently, nearly 38 million individuals in Southern California and the desert Southwest are under heat warnings, with temperatures regularly reaching the low 90s and even exceeding 100 degrees. This extreme heat is attributed to a massive heat dome that remains stagnant over the Western U.S.

In Palm Springs, California, Thursday’s temperature soared to an astonishing 107 degrees Fahrenheit, marking a new record for March. The previous record of 105 was set just a day earlier.

Additionally, the Coachella Valley city of Indio experienced record-breaking temperatures, reaching 108 degrees on Thursday—the highest ever recorded for March.

California witnessed numerous daily records, including a Thursday high of 101 degrees in Riverside. The day prior, a high of 95 degrees was established. Anaheim saw 88 degrees, while Sacramento recorded 85 degrees, according to the National Weather Service (NWS).

Over in Yuma County, Arizona, temperatures reached a remarkable 110 degrees on Thursday, setting a new record for the hottest March temperature ever recorded in the U.S., as confirmed by the National Weather Service.

Phoenix also recorded a high of 102 degrees on Wednesday, marking the earliest occurrence of triple-digit temperatures. On Thursday, temperatures escalated to 104 degrees.

“This is not just the first 100-degree day of 2026 but also the earliest recorded in Phoenix—previously occurring on March 26, 1988,” the NWS field office noted in a post on Wednesday.

Looking ahead, Phoenix is expected to see temperatures reach 106 degrees on Friday and Saturday, with a heatwave warning in effect until Sunday.

Las Vegas is also experiencing a surge in temperatures, setting a new March record of 95 degrees on Thursday. Local offices of the NWS predict temperatures could soar to 100 degrees on Friday, as reported by officials.

Regions in Oregon, Idaho, and Wyoming are also witnessing unusually warm conditions. The NWS office in Boise recorded a high of 80 degrees on Wednesday afternoon, marking the earliest date in history to reach that temperature since records began in 1875.

According to the NWS, this also marks only the second time Boise has reached 80 degrees in March since March 19, 1997, as stated in a post on X.

The extreme heat is forecasted to intensify over the weekend, moving eastward into the Rocky Mountains and the South-Central Plains.

“High temperatures are predicted to remain in the mid to upper 90s across Texas, while areas as far north as Nebraska and South Dakota could experience temperatures in the low to mid 90s,” the NWS stated on Thursday.

In Colorado, new temperature records are on the horizon, with Friday’s forecasted highs at 84 degrees in Denver, 86 degrees in Fort Collins, and 83 degrees in Boulder. The NWS has warned of increasing temperatures over the weekend.

This week’s heatwave is driven by a persistent ridge of high pressure that effectively traps hot air over the western United States.

While assessing the exact impacts of climate change on specific weather patterns is complex, it’s evident that global warming will lead to more frequent, intense, and prolonged heatwaves.