Hottest March temperature in US history recorded in Arizona

March 20, 2026

A desert community near Martinez Lake in Arizona's Yuma Desert set a new United States record for March temperatures when readings reached 43°C (110°F) on Thursday, surpassing the previous 42°C record from 1964. This record was part of an unprecedented late-winter heatwave affecting the southwestern United States, driven by a slow-moving high-pressure system that trapped hot air over the region. Multiple cities including Phoenix, Las Vegas, and locations in California also broke their March temperature records, with Phoenix experiencing its hottest March day ever at 40°C.

Who is affected

Residents of the desert community near Martinez Lake, Arizona
People living in Phoenix, Arizona
Residents of Las Vegas, Nevada
Communities near North Shore, California
Tourists visiting the southwestern United States during the heatwave
Populations throughout Arizona, California, and Nevada where records were broken

What action is being taken

The National Weather Service is monitoring and reporting temperatures
The Las Vegas, Nevada NWS office is issuing warnings about the dangerous heat conditions

Why it matters

This record-breaking heatwave is significant because it demonstrates the accelerating impacts of climate change, with extreme temperatures occurring months earlier than normal—typically such heat doesn't arrive until late May. The event is particularly dangerous due to its unusual timing during peak tourism season and because heatwaves are becoming more frequent, intense, and longer-lasting due to human-induced climate change. The breaking of a 60-year-old temperature record, along with multiple other records across several states, signals that historical temperature patterns are being dramatically disrupted, requiring urgent action to reduce greenhouse gas emissions.

What's next

No explicit next steps stated in the article

Read full article from source: BBC