The US is on the verge of an all-time heat record for March. Yes, it’s climate change

An unprecedented heat wave in the West is poised to break the record for hottest March temperature in the United States: 108 degrees. This is an alarming signal about the temperature of the planet and how quickly it is happening.

A weather station near Martinez Lake, Arizona, recorded a high temperature of 110 degrees Thursday afternoon, which some media outlets reported as a record. But this weather station is temporary and its accuracy is not monitored, according to the National Weather Service.

Lake Martinez’s temperature will not be considered a new national heat record in March unless the National Centers for Environmental Information decides to investigate. CNN has contacted NCEI for comment.

The national record was at least provisionally equaled Thursday afternoon. Indio and Thermal, California, reached 108 degrees at long-established, permanent weather stations.

All of this could be a moot point as the scorching heat wave continues through the weekend, with temperatures expected to peak near the national record in Southern California or Arizona.

An unusually strong and sprawling thermal dome is the catalyst for the heat, but its scale is undoubtedly made worse by pollution caused by global warming. Heat waves are becoming more frequent, more severe and lasting longer as the planet warms.

Climatologists at World Weather Attribution released an analysis Friday that said this heatwave would be “virtually impossible at this time of year in a world without human-induced climate change.”

Heated domes of this power are rare at the start of the year, and their arrival earlier than expected could actually make them more dangerous. “The early and prolonged nature of this heat with limited seasonal acclimatization will increase the risk of thermal impacts, particularly among sensitive populations or those without effective cooling,” the Weather Prediction Center said.

Extreme heat is the deadliest form of extreme weather in the United States, killing on average twice as many people each year as hurricanes and tornadoes combined.

Records are collapsing

More than 100 historic March records have already been broken or tied this week in several Western and High Plains states, including California, Arizona, Colorado, Idaho, South Dakota and Wyoming. And that’s not all: summer temperatures climb 20 to 40 degrees above average, even breaking all-time records in April.

Phoenix climbed to 102 degrees on Tuesday, easily breaking its previous March record of 100 degrees. It smashed it again on Thursday with a high of 105 degrees, even tying April’s monthly record.

A high of 84 degrees in Flagstaff, Arizona, on Thursday shattered the previous March record by 11 degrees and broke its April record by 4 degrees.

Denver, Las Vegas, Salt Lake City and Burbank, Fresno and Palm Springs, Calif., are some of the other cities where temperatures this week toppled March heat records.

Denver could even approach its April record high of 90 degrees by Saturday.

The heat dome will flex its muscles eastward over the next few days.

Dozens of cities, from Texas to South Dakota to the Carolinas, could at least break daily records.

Dallas-Fort Worth and Oklahoma City are among them, with highs expected to reach the 90s through this weekend. These temperatures rival the average for late June or July.

Lincoln, Nebraska’s capital, could even approach its all-time March high of 91 degrees by Saturday. The heat could worsen fire conditions across the state, including the one in Morrill County in western Nebraska, already the largest on record in the state.

As for the West, the record heat will continue for days into next week. Temperatures could break records in parts of Arizona, California and Nevada every day until at least next Wednesday.

There is no relief in the long-term outlook either, with above-average temperatures likely for the remainder of the month.

CNN meteorologists Mary Gilbert and Andrew Freedman contributed to this report.

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