Phoenix Swelters: Record Winter Heat Fueled by Climate Change

Meteorological winter concluded in Phoenix with an exceptional streak of record-breaking 90-degree days in late February and early March. The city experienced highs of 92 degrees on February 27th and March 1st, and 93 degrees on March 1st, shattering previous daily and monthly records.

This unusual warmth marks the warmest winter on record for Phoenix, with temperatures averaging about 3 degrees higher than the previous record set just last year. Across the Western United States, states from Washington to New Mexico logged record December highs, while Texas saw its first 100-degree day of the season exceptionally early.

Scientists attribute this phenomenon to a dual cause: the natural La Niña weather pattern and accelerating climate change. While La Niña typically brings drier and warmer winters to the region, the current trend of warming is significantly amplified by global climate shifts.

This extended period of unseasonable warmth has significant implications, including a diminished snowpack crucial for water supply and an increased risk of wildfires. Warmer winters strain water resources as snowpack is less robust and melts earlier, impacting reservoirs like Lake Powell and the Colorado River basin.

Experts warn that warmer winters contribute to an earlier start to the wildfire season. As of March 3, 2026, the outlook for spring remains uncertain, with predictions suggesting La Niña may transition to neutral conditions, potentially offering some chance of late-season snowfall.