weather heat wave conditions are tightening their grip across the western half of the United States, pushing early-season temperatures into record territory. In Los Angeles, California, the surge has already made it feel like mid-summer even though it is still March, with downtown Los Angeles reaching 91 degrees Fahrenheit on Wednesday. The National Weather Service said coastal temperatures likely peaked Tuesday, but inland heat would intensify before easing over the weekend.
What is happening now across the West
A long-duration heat wave is taking shape over the western half of the U. S. and is forecast to stick around in the days ahead. A high-pressure system over the West is keeping precipitation out, creating conditions for early-season heat across a large region. Triple-digit temperatures are baking the Desert Southwest, while cities closer to the Pacific Ocean are also seeing unseasonably high heat.
The scale of the heat has already shown up in records: more than 60 record-high temperatures were hit Tuesday, including 103 degrees in Palm Springs, California. The National Weather Service said above-normal temperatures are expected through the weekend, with more record-breaking daily highs and overnight lows possible. Forecasters also said the region could see prolonged heat into early next week.
Weather Heat Wave impacts in Los Angeles and record-setting Phoenix
In Southern California, the early-season heat has been felt sharply on the ground. One Los Angeles-area resident described the day as feeling like “the middle of summer, ” adding they would need to get into the shade soon. Another resident called the heat “too hot to be March, ” saying they did not want to imagine what July could feel like if this is the current baseline.
In Arizona, the heat has also crossed a milestone. Phoenix, Arizona, had its first 100-degree high of the year on Wednesday, the earliest that has ever happened. The last such record was set on March 26, 1988. Record keeping in Phoenix has been reported since 1896.
Warnings and advisories in effect through at least Sunday
Extreme heat warnings and heat advisories are in effect through at least Sunday across the Southwest and could possibly be extended. These alerts include major cities such as San Francisco, Los Angeles, San Diego, Palm Springs, Las Vegas, Phoenix, and Tucson.
The National Weather Service has urged people who must be outside for extended periods to drink plenty of water, take breaks in the shade or inside an air-conditioned building, and limit strenuous activities. The agency also warned that hot car deaths of young children rise during heat waves, a concern that can emerge well before the summer months.
Quick context: why this qualifies as a heat wave
A heat wave is defined as a period of unusually hot weather that typically lasts two or more days. Temperatures must be outside the historical average for a given area; for example, 100 degrees is typical in Phoenix during summer, but before the official start of spring it would be classified as a heat wave.
What’s next
The National Weather Service expects above-normal temperatures to continue through the weekend, with inland heat intensifying before easing over the weekend in Southern California. Forecasters said the broader region could see prolonged heat into early next week, and existing warnings and advisories may be extended. For now, the key message from officials remains immediate: treat this weather heat wave as a serious early-season risk, especially during extended outdoor activity and in vehicles.
