Spring Heatwave Causes Massive Snowmelt

In many parts of the Mountain West late March typically sees the highest annual snowpack. Snow from winter storms steadily accumulates from October or November before melting in late spring. But in 2026 a record-breaking March heatwave brought an early end to winter, resulting in the lowest snow water equivalent (the amount of water stored in the snow) ever measured in the region on April 1. In total, the snowpack held less than half of the normal amount.

These satellite pictures show the difference in snow cover from March 18, 2026, (above) and March 26, 2025, (below). 2026 snow cover extent was trending low even before the worst of the heatwave occurred.

A zoom into Park City, Utah, shows the rapid snowmelt caused by the heatwave. Site of most outdoor events in both the 2002 and 2036 Olympics, ski runs cover the mountain slopes above the town. On March 7, snow covered most of the hillsides surrounding the ski areas. By March 17 the snow had begun to recede, leaving the lower elevation ski runs visible as bright white streaks against the brown mountainside.

One week later even more snow had melted, remaining only on the highest elevation peaks and on the ski runs themselves. Two major ski areas — Park City Mountain Village and Deer Valley Resort — closed on March 29, three weeks earlier than planned.

The regional images were collected by the Visible Infrared Imaging Radiometer Suite (VIIRS) aboard NOAA-20, a polar orbiting weather satellite. Imagery from NASA’s Worldview. The high resolution images of Park City were collected by Sentinel-2 A, B, and C retrieved from the Copernicus Browser. Contains modified Copernicus Sentinel data 2026.