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Snow cover dropped in most of the US West during April, but still led to average snow cover overall, ranking twelfth in the 25-year satellite record. Snow water equivalent (SWE) decreased in every state in the western United States, with coastal states showing the largest decreases at individual stations.

Arctic sea ice extent through most of April changed very little. Only at the end of the month did extent begin to decline. Because the month started with unusually low extent, however, the average extent for April ended up tied for ninth lowest in the satellite record. The situation in the Antarctic remained fickle. Extent at the end of the month was tracking near the levels recorded for 2024, but well above the record low in 2023.

In November 2021, snow in South Greenland shrouded the ground when heavy rain fell, forming an ice crust and stranding hundreds of sheep in the rugged terrain. Most perished following this rain-on-snow event. The international Arctic Rain on Snow Study (AROSS), led by the National Snow and Ice Data Center, had not expected to hear similar stories of livestock decline caused by rain on snow events in southern Greenland like they had been hearing about in Alaska, Lapland, and Russia. The event in South Greenland marked an opportunity for AROSS to offer knowledge exchange across different cultures, cultural practices, and environments under an increasingly unpredictable climate.

Snow-covered area in March across the western United States was 8 percent below average, ranking seventeenth in the 25-year satellite record. Snow cover duration was just above the twenty-fifth percentile. Snow albedo, also known as snow brightness, started low in early March and then oscillated between high, then low, and then high during the month. Snow water equivalent (SWE) relative to average showed little change during the month, despite SWE gains at many stations across the region.

Arctic sea ice has likely reached its maximum extent for the year, at 14.33 million square kilometers (5.53 million square miles) on March 22, according to scientists at the National Snow and Ice Data Center (NSIDC) at the University of Colorado Boulder. The 2025 maximum sea ice extent is the lowest in the 47-year satellite record, falling short of the previous record low of 14.41 million square kilometers (5.56 million square miles) set on March 7, 2017.