The Northwest experienced its warmest August–November period on record, producing warm rains instead of typical mountain snow and leaving regional snowpack at its lowest winter level since 2001. Scientists say warm storms melted existing snowpack and contributed to drought in parts of Idaho, Washington and Oregon. While recent rains have refilled some reservoirs, most of Oregon is below normal in both precipitation and snowpack. Experts warn that unless cooler, snow-producing systems arrive soon, drought stress could continue into next year.
Northwest Records Warmest Fall On Record; Lack Of Snowpack Raises Drought Alarm
Photo: A minivan stranded by floodwater on Tualco Road near Monroe, Washington, on Dec. 13, 2025 — a visible effect of the unusually warm, rainy conditions across the region this fall.
Scientists warn that a record-warm autumn combined with a failure to build typical mountain snow has heightened drought stress across Oregon, Idaho, Washington and western Montana as the region moves into winter.
Record Warmth, Fewer Mountains Of Snow
Data from the National Oceanic and Atmospheric Administration show the Northwest experienced its sixth-warmest August, the warmest September (about 6°F above average) and the second-warmest November on record. Taken together, August through November 2025 was the warmest such period across the Northwest in more than 130 years of records.
On a global scale, NASA scientists using NOAA temperature records dating back to 1880 ranked November 2025 as the third-warmest November on Earth, trailing only November 2023 and 2024. Unlike those years, however, there was no El Niño event driving temperatures this year.
Snowpack Shortfall And Hydrological Impacts
Jacob Genuise, a climatologist at the Washington State Climate Office, said snowpack across the Northwest and in the Cascade Range is "simply not piling up." He warned that regional snowpack is at its lowest winter level since record keeping began in 2001. "We're seeing really warm storms with a lot of rain and not a lot of snow," Genuise said. "Given all this warm rain, it actually melted some of our snowpack, and we saw a decline."
Snowpack acts like a natural reservoir, slowly releasing water during spring and summer. When snow is replaced by rain, reservoirs may initially fill, but communities that depend on snowmelt for summer water supplies face greater risk of shortages later in the year.
Current Conditions And Regional Outlook
Brad Pugh, a meteorologist with the National Weather Service's Climate Prediction Center, noted that most of western Oregon received only about 50% of its normal precipitation last month. While parts of western Washington and earlier heavy spring rains in central and southern Oregon have replenished some reservoirs, those gains can be quickly drawn down.
Areas north of Oregon have seen above-average rainfall recently, which could help relieve drought in the coming weeks or months. Much of the relief, however, depends on whether temperatures fall enough to turn rain into mountain snow and rebuild the crucial snowpack.
At present, western Montana is the only subregion with roughly normal snowpack because temperatures there have been marginally cold enough for rain to switch to snow. By contrast, all of Oregon and much of southern Washington are suffering "really, really deep snowpack deficits," Genuise said. If snowpack remains low through spring, drought conditions could persist into next year.
Bottom Line: Warm, rain-heavy storms this fall have reduced mountain snow and pushed snowpack to record lows for the season in many places. Short-term reservoir refills in some areas may not offset the longer-term risk of drought if cooler, snow-producing systems do not arrive.
What To Watch: Forecasters will be monitoring incoming systems for a shift to colder, snow-producing weather. Local water managers and communities that rely on snowmelt should prepare for continued hydrological stress if mountain snow remains sparse.
