Record Heat and El Niño Threaten Colorado River Basin

Russ Schumacher, Colorado’s state climatologist, didn’t need a crystal ball to tell us the winter was breaking records. He just needed to look at the data. December and February shattered temperature records across the state. Then came March, a month that should have been deep in snowpack accumulation, instead delivering a "heat dome" that pushed Fort Collins past 90 degrees — a threshold not usually seen until June.

Now, the forecasters are pivoting to a new variable: El Niño.

The Washington Post reported Monday that the risk of an El Niño event is rising. This isn’t just a mild warming of the Pacific; this could be the strongest in 140 years. Paul Rondy, a professor of atmospheric science at the State University of New York at Albany, wrote that there is "real potential for the strongest El Niño event in 140 years." The implication? A hotter-than-average summer for the Western United States, continuing into 2027.

Let’s look at what we’re already dealing with. The Colorado River Basin is in trouble. Average daily temperatures in March were the warmest on record. That heat cooked the snowpack before it could fully settle. Jeff Lukas, a consulting climate researcher, put it drily on LinkedIn: "March was not … helpful." He noted record heat and near-record-low precipitation in what should be one of the snowiest months. The result? The basin-wide snowpack peaked at the earliest date and lowest level on record.

The numbers in our local drainages tell the story of a system running on fumes. On April 1, the Eagle River drainage was sitting at just 21% of its 30-year average. The Roaring Fork River was at 26%. The Yampa? 20%. The San Juan was down to 17%. In all these cases, snowpack had fallen by half or more compared to March 1.

Lake Powell, already shrunken to 24% or 25% of capacity, is losing ground fast. As of Tuesday, the reservoir level was down almost 31 feet from a year ago. The Colorado River Basin Forecasting Center predicts flows into Powell will be only 22% of average. Rain and snow could still help, but for the next 10 days, they aren’t likely.

We have two historical benchmarks for "awful" flow years since Glen Canyon Dam was completed in the 1960s: 1977 and 2002. In 2002, flows into Powell were shockingly low, about 25% of average. But there’s a critical difference now. Margins have narrowed. In 2002, Powell started the century at 94% full. Today, it’s barely a quarter full.

Becky Bolinger, a climate researcher in Colorado, pointed out on LinkedIn that the current forecast projects April-through-July flows will be slightly greater than 2002. But she added a stark warning: "I think it is entirely plausible that the actual volume for 2026 comes in as a new record low."

If El Niño delivers on its promise of hotter temperatures, that 2026 projection moves from plausible to probable. For locals, this isn’t just about whether the river runs in July. It’s about water rights, agricultural viability, and the cost of pumping water from lower elevations as the snowline moves up. The heat dome broke the record; El Niño might break the bank.