Day: March 17, 2026

Record high temperatures compound low-#snowpack problems: 75% of days from November to February were warmer than average — Laurine Lassalle (AspenJournalism.org)

Snowpack in the Roaring Fork Valley basin is at 65% of normal as of March 13 — the lowest level recorded since the modern snowpack telemetric system started collecting data in 1981. The North Star Nature Preserve east of Aspen, typically snowcovered in March, was nearly bare on March 12. CREDIT: LAURINE LASSALLE/ASPEN JOURNALISM

Click the link to read the article on the Aspen Journalism website (Laurine Lassalle):

March 13, 2026

Temperature and precipitation data in the Roaring Fork Valley shows that most of this winter has experienced above-average temperatures with below-average precipitation, making this season one of the hottest and driest on record.

“We notice [the lack of snow] because [it’s visible], but we keep on having these crazy-warm years, and at the end of the day, that’s what’s going to be the driver of change,” said Adam McCurdy, forest and climate director at Aspen Center for Environmental Studies (ACES). He predicts that big snow years will return, but that the long-term warming trend will continue in a way that’s “going to move spring runoff, it’s going to change water availability even if we, say, keep the same snowpack.”

According to NOAA’s Climate at a Glance tool, Pitkin County experienced its second warmest and 10th driest winter on record, with data going back as far as 1895, as average daily temperatures from November through February reached 26.9 degrees this winter, or four degrees above normal, behind the winter of 1906-07’s record high of 27.5 degrees. The county received 6.9 inches of precipitation, including rain and snow, behind 1903-04’s 3.55 inches, 1980-81’s 5.16 inches and 1976-77’s 5.21 inches. 

February average temperatures at the Aspen-Pitkin County Airport reached a record high this year, at 31.6 degrees Fahrenheit, which is about six degrees above normal, according to data from the local National Oceanic and Atmospheric Administration (NOAA) station, which began collecting climate data in 1998.

Although this winter’s lack of snow is striking, with measured levels reaching record lows, rising temperatures might be cause of greater concern as part of a larger trend, impacting spring runoff and local forests. Experts hope that precipitation this spring and summer can still bring the necessary moisture to mitigate current drought conditions. 

Snowpack in the Roaring Fork Valley basin is at 65% of normal as of March 13, according to SNOTEL, which is the U.S. Department of Agriculture’s automated mountain weather network, and Aspen Journalism’s snowpack dashboard. It’s the lowest level recorded since the modern snowpack telemetric system started collecting data in 1981. At Independence Pass, snowpack reached 56% of normal on March 13, but state climatologist Russ Schumacher told Summit Daily on March 4 that monthly hand measurements, which go back nearly a century, show that this year’s snowpack at Independence Pass was among the lowest 3% of the 88 years on record.

The SNOTEL station at McClure Pass in 2023, when snowpack held 23.6 inches of snow water equivalent on March 13, well above the 8.3 inches on March 13, 2026. CREDIT: HEATHER SACKETT/ASPEN JOURNALISM

According to a climate sensor located at the city of Aspen’s water department in the Castle Creek Valley, where snowfall, temperature and precipitation data has been tracked since 1934, a total of 71.5 inches of snow fell from November through February, making this winter the driest in the past 30 years and the 12th driest on record, behind the winter of 1976-77, which received 47.5 inches of snow from November through February, and the 1980-81 season, when city records recorded 40.9 inches of snow. It’s worth noting that the station at the city’s water plant has moved locations over the years and changed its equipment in the 1980s, so comparisons using data collected before those changes may be skewed.

A total of 6 inches of precipitation, including rain and snow, fell on the Roaring Fork Valley between November and February, according to Gridded Surface Meteorological (or gridMET) data that goes back to 1979. That’s below last year’s 8.5 inches and represents 55% of the 30-year average, making the 2025-26 winter season the second driest, after 1980-81. Although precipitation has been below average, McCurdy said wide variations in rain and snow totals year over year are expected. “While this is an exceptionally dry winter precipitationwise, it’s not outside of the range of historic variability,” McCurdy said. “What we’re seeing temperaturewise is … certainly where we’re heading and we’ve seen it again and again. So I think that’s not just one data point, it’s another data point in a long-term trend.”

While this winter’s lack of snow is striking, rising temperatures might be cause of greater concern as part of a larger trend, impacting spring runoff and local forests. CREDIT: LAURINE LASSALLE/ASPEN JOURNALISM

Above-average temperatures are becoming more common

NOAA’s 2018 modeling trend shows that average daily temperatures from November through February in Pitkin County have increased by 0.3 degrees every 10 years, mostly driven by rising low temperatures that have gone up by 0.5 degrees every decade. According to the 2024 Colorado Climate Change Report from the Colorado Climate Center, annual average temperatures across the state warmed by 2.3 degrees from 1980 to 2022 and are expected to keep rising due to climate change. By 2050, statewide annual temperatures are projected to increase by 2.5 to 5.5 degrees compared with 1971-2000, and between 1 degree and 4 degrees compared with 2022, under a medium-low emissions scenario.

Colorado statewide annual temperature anomaly (°F) with respect to the 1901-2000 average. Graphic credit: Colorado Climate Center

“Colorado has warmed at a faster rate than the global average and is expected to continue to warm,” Peter Goble, assistant state climatologist at Colorado State University’s Colorado Climate Center, told Aspen Journalism. “Having said that, not every winter going forward is going to be as warm as this winter. And, in fact, I think this winter was so unusual that I think this winter will be considered a much-warmer-than-normal winter for some time to come.” 

The impact of this warm and dry winter will be seen in the spring runoff as a much-lower-than-average peak runoff is to be expected, but summer conditions are still uncertain as experts hope for spring and summer precipitation that would lessen drought conditions. CREDIT: LAURINE LASSALLE/ASPEN JOURNALISM

The NOAA sensor at ASE recorded 94 days with above-average minimum temperatures out of the 120 days from November to February, and 89 days with above-average maximum temperatures, for a total of 81 days with both above-average minimum and maximum temperatures. In other words, about three-fourths of the days were warmer than normal. In comparison, November 2024-February 2025 had 54 days with above-normal temperatures.

Looking at the Roaring Fork Valley as a whole, gridMET data shows that this winter counted 92 days with above-average daily temperatures, above 2005’s 85 days. The GridMET dataset from scientists at the University of California Merced combines data from weather stations in a given area and uses modeling to generate surface climate datasets instead of relying on one specific weather station. 

The data also shows that warm winters have become more frequent since the mid-1990s. According to gridMET data, which goes back to 1979, winters in the dataset in prior years with the highest number of days with above-average temperatures include 2018 and 1981, but 1981 was followed by a decade of mostly cooler temperatures and above-average precipitation. “On the other hand, 2018 and 2026 are both part of consistently hotter-than-average winters and, more recently, drier starts to the season,” according to ACES.

Although the entire state of Colorado is experiencing drought conditions, the upper Roaring Fork Valley has been experiencing “exceptional” drought conditions since Dec. 23, according to the U.S. Drought Monitor, with about 28% of Pitkin County and 19% of Eagle County experiencing such conditions as of March 10. (“Exceptional” is the most severe level.) The Roaring Fork watershed is one of the only two places throughout the entire West to experience this level of drought. 

Colorado Drought Monitor map March 10, 2026.

“One of the main reasons that, when you look at the U.S. Drought Monitor, the Roaring Fork Valley stands out is because of the mix of both short- and long-term drought conditions in place,” Goble said, adding that the Roaring Fork Valley was very hot and dry last summer, while other areas around the Colorado Rockies received some decent moisture. “The Roaring Fork Valley was already en route [to drought] going into this winter season,” he said.

Average daily temperatures, or the average of high and low temperatures, in the Roaring Fork River watershed have been 5 degrees above 1991-2020 historical average this winter (November-February), surpassing the previous record year of 1981, when temperatures were 4 degrees above normal. For February, average temperatures for the Roaring Fork Valley were the fourth highest on record, at 27.6 degrees.

Maximum and minimum temperatures are getting closer

On average, maximum and minimum temperatures recorded at ASE have both been approximately 6 degrees higher than normal in February. From November through February, maximum and minimum temperatures have also been roughly 6 degrees above normal. Last winter, maximum and minimum temperatures were, on average, 1 degree below normal.

GridMET data shows that, on average, maximum and minimum temperatures are getting closer, a trend that has been particularly noticeable in the past five to six years. The gap for November through February reached an average of 19.7 degrees for the Roaring Fork Valley, the lowest reading on record. 

Rising low temperatures can affect the ability to make snow at ski resorts, as reported byAspen Journalism in 2019 and The Sopris Sun in January, while the need to rely on snowmaking to compensate for the lack of snow increases. 

McCurdy explained that snowpack maintains and accumulates “cold content” during the winter and that low nighttime temperatures allow this thermal buffer to form and keep snowpack colder longer, preventing it from melting too fast. 

“Before the snow starts to rapidly melt, the snowpack needs to become isothermic; in other words, the entire [snowpack] column is about 0 degrees Celsius [32 degrees Fahrenheit] and ready to melt,” he said. “Because of the warm winter [and the rising low temperatures], the snowpack is entering spring closer to isothermic, which could result in a pretty rapid melt-off.”

Historically, the gap between high and low temperatures averages 22.6 degrees. According to NOAA, 25.5 degrees separate high temperatures from low temperatures at ASE for this winter, lower than last year’s 26 degrees but higher than the nearly 25 degrees recorded in the winters of 2023-24 and 2022-23.

Possible impacts

“The real impact of this warm, dry weather will be seen in the spring runoff,” McCurdy said, adding that a much-lower-than-average peak runoff is to be expected. 

He said most trees are dormant during the winter until spring runoff, when they pull up a lot of water to use for the rest of the summer, but if their water supply is low, they’re not going to be able to grow as much or be able to produce resins and chemical defenses to fend off things such as bark beetles and other invasive insects.

“Trees have a long hydrologic memory,” he said. “One year isn’t as impactful to them as some other species where they’ll build up water. They have deep roots. They can pull up groundwater, but by the same token, multiple years of drought is a hard hole for them to get out of.”

McCurdy said the aspen population, for example, has declined and dry winters tend to negatively affect them. “Assuming we don’t get more precipitation, we could lose more aspens.”

Pitkin County experienced its second warmest and 10th driest winter on record, with data going back as far as 1895, as average daily temperatures from November through February reached 26.9 degrees this winter. A sensor on Castle Creek recorded a total of 71.5 inches of snowfall from November through February, making this winter the driest in the past 30 years. While most of the terrain on Aspen Mountain is still covered enough for skiing, some slopes have begun to melt out. CREDIT: CURTIS WACKERLE/ASPEN JOURNALISM

Goble said the lack of snow will probably lead to below-normal water supplies and impact river recreation, and it could lead to higher fire danger. Major factors that contribute to a large wildfire season in Colorado are low snowpack, early snowmelt and a hot summer. As of early March, snowpack is certainly low and early spring runoff is expected, but the severity of summer conditions is still uncertain. 

“Just because things have been dry recently doesn’t mean that we’ll continue to be dry in summer,” Goble said. “Large wildfires are not a guarantee yet at this point, but I do think that with the very low snowpack numbers that we have in place now, it’s a higher probability than a normal year.”

Although the entire state of Colorado is experiencing drought conditions, the upper Roaring Fork Valley has been experiencing “exceptional” drought conditions since Dec. 23. The Roaring Fork watershed is one of the only two places throughout the entire West to experience this level of drought. An almost snow-free south-facing hillside above the North Star Nature Preserve is shown here on March 12. CREDIT: LAURINE LASSALLE/ASPEN JOURNALISM

Although a change in the weather that would bring precipitation levels closer to average would not be unprecedented, it is also statistically unlikely.

“In our 47-year record, there is only a single year that had enough precipitation to dig us out of the hole we’re currently in. In 1995, from this point in February until the end of May, there were 22 inches of precipitation; that’s about double the average precipitation that normally falls over that period,” according to an ACES blog post. “Based on a model of total precipitation for this period, we have a roughly 1% chance of ending the year with a normal amount of precipitation.”

Goble agrees that the chances to get back to normal snowpack this year are slim. “We just don’t have enough winter left to make up the deficits that are already in place. It would take a record kind of mid-to-late March through April in order to get us back up to normal,” he said. “But that doesn’t mean that spring and summer precipitation isn’t important. If we have a wet spring or and we have a wet or cooler-than-normal summer, those types of things could mitigate some of the drought impact that we might otherwise see this summer.”

Record heat could put #ColoradoRiver closer to crisis — Tucson.com #COriver #aridification

Udall/Overpeck 4-panel Figure Colorado River temperature/precipitation/natural flows with trend. Lake Mead and Lake Powell storage. Updated through Water Year 2025. Note the tiny points on the annual data so that you can flyspeck the individual years. Credit: Brad Udall

Click the link to read the article on the Tucson.com website (Tony Davis). Here’s an excerpt:

March 14, 2026

The record-breaking heat in this month’s forecast is likely to help push the Colorado River Basin to the edge of “disaster,” in which drastic cuts in water use will be necessary next year, experts say.  The heat is almost certain to slash river flows even more than already expected after the snowpack in key sites above Lake Powell hit record lows this winter. The upshot: Lake Powell is likely to get less than one-third the water from the river that it would in an average April to July. The unusually low flows won’t be bad enough to push the basin into immediate disaster this year. But several experts said it is virtually inevitable that major cuts in river water use will be needed next year in Arizona and other Western states — unless the winter of 2026-27 is far cooler and wetter than the current one.

“We can survive this year, no problem. What’ll be interesting to see is if this year puts enough scare into the states to begin real serious rethinking about how we manage water,” said David Wegner, a retired U.S. Bureau of Reclamation planner and congressional staffer who now sits on a National Academy of Sciences board that reviews water issues.

The Bureau of Reclamation already projected, in February, that Lake Powell is likely to fall below the level at which the turbines at adjoining Glen Canyon Dam can generate electricity — 3,490 feet — by December 2026. Given the trend toward lower snowpack, higher temperatures and less runoff of water into the river, it’s very possible if not likely, that future forecasts will show the lake falling below 3,490 feet sooner than December. But most observers, including Kuhn and Wegner expect the bureau to try to forestall that possibility in advance by releasing extra water from reservoirs upstream of Lake Powell, led by Flaming Gorge reservoir at the Utah-Wyoming border. Powell is at the Arizona-Utah border.

Not looking good at all — Allen Best (BigPivots.com) #snowpack #runoff

Click the link to read the article on the Big Pivots website (Allen Best):

March 6, 2026

Might the Colorado River runoff be as bad as 2002? March could bring snow and rain. Almost certainly it will bring warm temperatures.

What if March brings temperatures suitable for flip flops in places like Steamboat, Vail and Telluride? And what if the snow that does fall on the headwaters of the Colorado River is average or less?

Things could get much more grim in the Colorado River Basin this year, conceivably as bad as 2002. That year was memorable for the pitiful runoff, the peak barely discernible in Glenwood Canyon in April and May. Worse came in June when three fires erupted at very nearly the same time.

The Hayman Fire (2002) was the state’s largest recorded wildfire. Smoke from the massive blaze could be seen and smelled across the state. Photo credit to Nathan Bobbin, Flickr Creative Commons.

Bill Owens, who was then Colorado’s governor, toured the state by plane, visiting the Hayman fire that started near Colorado Springs, the Coal Seam Fire at Glenwood Springs, and the Missionary Ridge Fire north of Durango. “All of Colorado is on fire,” he said, a remark that some, concerned about impacts to tourism, derided as an overstatement. But within that statement was a certain truth.

This week, NOAA’s Colorado River Basin Forecast Center released its projected flows into Lake Powell. It doesn’t look pretty. Jeff Lukas, the principle at Lukas Climate Research and Consulting, assembled this graphic that shows how the projections visually compare to other years since 1991.

“Despite better snowfall in February, the most probable forecast remains bleak at 36% of average,” he said on LinkedIn. That, he added, would put runoff in the observed flows into Powell in 2012, 2013, 2018, 2021, and 2025. “In other words, a bad neighborhood,” he said.

An unusually wet and cool March through May would only get the inflow to 65% of average. On the other hand, it could go in the other direction. A warm and dry March could eviscerate the existing snowpack.

James Eklund, a water attorney and former director of the Colorado Water Conservation Board, pointed out that the long-term average has been 6.7 million acre-feet. The March forecast projected runoff of around 2.3 million ace-feet.

Colorado transmountain diversions via the State Engineer’s office

“The river cares not about our legal arguments,” he said in a LinkedIn post, a reference to the intense squabbling about how to share a river that has been rapidly diminishing in average volume in the 21st century. Even in places like Arvada, people who don’t realize that they are watering their lawns and taking their showers with water imported from a Colorado River tributary do realize the Colorado River has problems.

The runoff could conceivably be worse than 2002. There’s a big difference, though. In 2002, the reservoirs held a great deal of water. Not completely full, but within a good water year of being full. Total runoff that year was 25% of average. Most years since then have been below average, leaving water levels of Powell within striking distance of deadpool.

From his post in the Glenwood Springs area, Eric Kuhn sees March storms having potential to bump up the runoff numbers. “This is one of those years where March could make a big difference. But when I look at the outlook for three or four weeks, it looks like March will definitely be above average in temperatures, which is not good news. I think it’s too soon to tell whether we will have average or below average precipitation. But warm temperatures will not be good to the snowpack.” [ed. emphasis mine]

This year’s runoff will add tension to the already fraught situation in the Colorado River Basin. Kuhn, a former manager of the Colorado River Water Conservation District, said he wouldn’t be surprised if the Bureau of Reclamation — an agency within the Department of Interior that oversees operation of the federal dams — finds it must release one million acre-feet less than the base 7.5 million acre-feet release.

This could trigger a legal fight. The Colorado River Compact imposes a requirement upon the upper Colorado River Basin states to deliver 75 million acre-feet on a rolling 10-year average. This would take the upper-basin states below that threshold.

That provision in the compact has been debated almost since Congress approved it in 1929. But, under the most aggressive interpretation by lower-basin states, this could put the upper-basin out of compliance. As such, this could be the year that puts the basin states on long road to a U.S. Supreme Court review.

A meager runoff this year will also put the Department of Interior into an uncomfortable position of having to make decisions. Kuhn says the federal agency’s water officials have traditionally tried to mediate disputes among the seven basin states. This year the agency might have to make decisions that leave people upstream and down unhappy.

“They could sit back (in former days) and say we are not going to take a position because we don’t want to upset either side. We have to work with both sides. Those days have come to an end, unfortunately.”

Map of the Colorado River drainage basin, created using USGS data. By Shannon1 Creative Commons Attribution-Share Alike 4.0