Last month's record-breaking heat across the Mountain West led to the worst snowpack on record in Colorado and Utah, along with a significantly downgraded forecast for the upcoming supply of Colorado River water.
Cody Moser with the federal Colorado Basin River Forecast Center said in a monthly briefing Tuesday that just 1.4 million acre feet of Colorado River water is expected to reach Lake Powell through July. That's less than a quarter of what's considered normal.
It's also much lower than the 2.3 million acre feet Moser's office projected a month ago, before the heat wave in the West melted away an already meager supply of snowpack.
"With record low snow pack, we have well below normal water supply forecasts," he said. "In many cases, our April through July (water) volume forecasts rank in the lowest five on record when compared to historical observations."
The forecast for how much water will reach Flaming Gorge Reservoir also dropped more than 20% since the last monthly projection. Flows for the Yampa River are also projected to be near the record low.
Moser added it's likely some rivers and streams in western Colorado have already reached their peak runoff for the year.
He said the water supply forecasts could improve if wet conditions arrive, or decline even further if the West remains dry.
The worsening river forecasts arrive as the seven states that use the waterway remain at an impasse this spring over how to share and conserve the water in the future.
Negotiators missed a February deadline to strike a deal but have said in recent weeks their talks are continuing with a focus on a potential short-term plan.
If states can't reach a deal, the Interior Department is expected to identify its preferred option for how to manage Lake Powell and Lake Mead after the current operating guidelines expire this fall.
Interior Secretary Doug Burgum told Arizona radio station KTAR News this week that the worsening spring runoff conditions are going to "require everybody to dig in and take bigger cuts than they want, and we haven't reached that spot yet."
This story is part of ongoing coverage of the Colorado River, produced by KUNC in Colorado and supported by the Walton Family Foundation. KUNC is solely responsible for its editorial coverage.