Colorado River Basin snowpack below one-third

Snowpack is the Colorado River Basin’s natural savings account. It builds in winter, melts in spring, and feeds rivers and reservoirs when the hot months arrive. This year, that account got drained early. By May 8, Colorado’s own water-supply update was describing a runoff season that arrived weeks ahead of normal and was already slipping into recession across many rivers. ### What actually broke this winter? The core problem was heat as much as dryness. Colorado water managers say the 2026 water year has been defined by a record warm, dry winter, with March ranking as the warmest on record in the Colorado Basin River Forecast Center area. That meant less snow accumulation, more precipitation falling as rain, and a snowpack that spent months near the bottom of the SNOTEL record. (nrcs.usda.gov) ### Why does “below one-third” matter so much? Because May is when the snowpack is supposed to be cashing out into streamflow. If there is very little snow left by early May, there is less water still waiting in the mountains for late spring and early summer. Colorado’s statewide snowpack was 20% of median on May 1 and only 25% by May 7 after a helpful storm. On May 9, the statewide figure was still just 22% of median. That is not a small miss — it is a system running on scraps. (nrcs.usda.gov) ### Where is the damage showing up first? In runoff forecasts. Colorado’s May-through-July runoff forecast sits at 24% of median statewide, with western-slope basins mostly in a 22% to 24% range. Forty-eight of 86 forecast points are either the lowest or second-lowest in their period of record, and all 86 rank at or below the 13th percentile. In plain English — this is not just bad, it is historically bad across a lot of gauges at once. (nrcs.usda.gov) ### What does early melt change on the ground? Timing. Water is arriving earlier, peaking earlier, and then fading sooner. The Yampa River near Maybell already hit its seasonal peak at the end of March — the earliest peak date and lowest peak in 110 years of record. Similar shortened hydrographs are showing up in the Upper Colorado region and southern basins. Think of it like getting your whole paycheck on the first day of the month and then having to stretch the leftovers much longer than usual. (nrcs.usda.gov) ### Does a May storm fix any of this? Not really. The first week of May brought unsettled weather and some fresh snow in northern headwaters, but forecasters are clear that the bigger pattern is still an early peak, low snowpack, and low runoff. A late storm can slow melt for a moment or add a little water at high elevations, but it does not rebuild a winter that never really showed up. (nrcs.usda.gov) ### Why does this matter for Lake Powell? Because Powell depends on what happens upstream in the Upper Colorado Basin. Reclamation’s latest Glen Canyon Dam update projects 2026 unregulated inflow to Lake Powell at 3.87 million acre-feet — 40% of average. Powell ended March at 5.72 million acre-feet, or 25% of live capacity, and operators are already managing releases to protect elevation targets. Low mountain snow turns very quickly into reservoir stress. (cbrfc.noaa.gov) ### Is this just a Colorado story? No — it is a basin-management story. Colorado is a major source region for the Colorado River system, so a bad snow year there ripples into reservoir operations, water deliveries, hydropower planning, and fire-season risk windows across the broader West. The catch is that shoulder-season weather still matters a lot now. When the snowpack is this thin, a hot spell, a freeze-thaw swing, or one decent storm can move conditions fast — but from a very low base. (usbr.gov) ### Bottom line? The news is not just that snowpack is low. It is that the basin has already spent much of the little snow it had — weeks early — and the water system downstream now has to live with that. (nrcs.usda.gov)