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 on the verge of breaking the record for the hottest March temperature anywhere in the United States: 108 degrees. It’s an alarming signal of how hot the planet is getting and how fast it’s happening.

A weather station near Martinez Lake, Arizona, posted a high temperature of 110 degrees on Thursday afternoon, which some media outlets reported as the record-breaker. But that weather station is a temporary one and not quality controlled for accuracy, according to the National Weather Service.

The Martinez Lake temperature won’t be deemed a new national March heat record unless the National Centers for Environment Information decides to investigate it. CNN has reached out to NCEI for comment.

The nationwide record was at least preliminarily tied on Thursday afternoon. Both Indio and Thermal, California, hit 108 degrees at permanent, long-standing weather stations.

It could all 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 heat dome is the catalyst for the heat, but the magnitude is undoubtedly being worsened by planet-warming pollution. Heat waves are becoming more frequent, more severe and lasting longer as the world warms.

Climate scientists at World Weather Attribution published an analysis Friday that found this heat wave would be “virtually impossible for this time of year in a world without human-induced climate change.”

Heat domes of this strength are rare this early in the year, and its arrival ahead of schedule could actually make it more dangerous. “The early, prolonged nature of this heat with limited seasonal acclimation will increase the risk of heat impacts especially among sensitive populations or those without effective cooling,” the Weather Prediction Center said.

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

Records are tumbling

More than 100 all-time March record highs were already broken or tied this week across several states in the West and High Plains, including California, Arizona, Colorado, Idaho, South Dakota and Wyoming. And there’s more to come: The summerlike temperatures are spiking 20 to 40 degrees above average, which has even broken all-time April records.

Phoenix soared to 102 degrees on Tuesday, easily besting its previous March record of 100 degrees. It shattered it again on Thursday with a high of 105 degrees, which even ties the April monthly record.

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

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

Denver could even soar to near its April record 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 east to the Carolinas could at least break daily record highs.

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

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

As for the West, the record heat will drone on and on for days well into next week. Temperatures could break record highs in parts of Arizona, California and Nevada every day through at least next Wednesday.

There’s no relief in the longer-term outlook either, with above-average temperatures likely through the rest of the month.

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

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