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Colorado Climate Center @climate.colostate.edu · 09/09/2026

NOAA data confirms that we just went through the warmest August and the warmest climatological summer (June-July-August) on record for Colorado. Stay tuned for our monthly summary (coming soon!) which will include stats on the many, many records broken this summer. #cowx

"Quadrant chart" showing precipitation on the horizontal axis and temperature on the vertical axis for all June-July-August periods since 1895 in Colorado. 2026 stands above all other years as the warmest summer on record. It was also the 22nd driest summer.

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Colorado Climate Center @climate.colostate.edu · 04/09/2026

...but the correlation with mountain snowpack (the source of our water) is frustratingly weak. Statewide, the correlation between ENSO and peak snow water equivalent is effectively zero, though there is some modest positive correlation in southern Colorado (i.e., greater snowpack in El Niño years).

Correlation between peak snow water equivalent and Oct-Feb Relative Oceanic Nino index. Statewide correlation is 0.05. There are modest positive correlations in the southern basins and even smaller negative correlations in the north.

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Colorado Climate Center @climate.colostate.edu · 04/09/2026

Historically, El Niño has increased the chances for wetter-than-average conditions in Colorado, especially in fall and spring...

General Relationship Between Colorado Precipitation and El Niño
Southern Oscillation (1950-2025)

Green: El Niño tends wetter
Blue: La Niña tends wetter
Masked for statistical significance:
95% confidence

There is more green than blue on the maps across all seasons, indicating that El Nino tends to be wetter, especially in spring and fall.

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Colorado Climate Center @climate.colostate.edu · 14/08/2026

Colorado Flood Threat Bulletin shows a high risk of flash flooding again today (Friday August 14) in northeastern Colorado and along the Palmer Divide. Be weather aware and stay safe! #cowx www.coloradofloodthreat.com

Map of the Colorado Flood Threat Bulletin for Friday August 14, 2026, showing a moderate risk over all of northeastern Colorado and a high risk along the Palmer Divide. From https://www.coloradofloodthreat.com

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Colorado Climate Center @climate.colostate.edu · 11/08/2026

July is the hottest month of the year in Colorado, and this July was the 2nd hottest on record. Records were broken for both hot days and warm nights. The monsoon finally arrived, bringing welcome rain but unwelcome flash flooding. Read more in our July summary! climate.colostate.edu/monthly_summ...

July 2026
Colorado Monthly Climate Summary
Maybell: 102°F
Leroy 5 WSW: 79°F
•
Greeley UNC: 76°F •
Grand Lake 6 SSW: 57°F•
Brighton 3 SE: 105°F
Denver Lowry AFB: 79°F
Collbran: 100°F
Grand Junction
•
Walker Field: 80°F
Evergreen: 64°F•
Twin Lakes
Reservoir: 89°F
•• Aurora Buckley Field ANGB: 75°F
° Kassler: 76°F
• Limon: 70°F • Burlington: 113°F
• Grand Junction
6ESE: 78°F
• Palmer Lake: 69°F
Lake George•
8 SW: 89°F
Fort Carson Butts AAF: 76°F
•
Montrose No 2: 73°F •
Cochetopa Creek: 59°F
Blue Mesa Lake: 96°F
_Fort Carson Butts AAF: 101°F
••
Sargents: 97°F- • Pueblo Reservoir: 75°F
Grand Sand Dunes
National Park: 66°F
Cortez: 102°F
Walsh 1 W: 110°F
•
Alamosa-Bergman Field: 59°F
All-Time Record High Max All-Time Record High Min
Stations with records > 50 years
Data from ACIS
All-time record temperatures tied and broken in July 2026
Statewide Temperature and Precipitation Ranks for July 2026 (based on 1895-2026 data)
2nd warmest (above average) • 45th driest (near average)

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Colorado Climate Center @climate.colostate.edu · 10/08/2026

*Big* pattern change on the way later this week, as the ridge of high pressure and heat finally fades and rain chances increase considerably statewide. Here's hoping for some real drought relief (and minimal flash flooding). #cowx

NOAA Weather Prediction Center 7-day precipitation forecast and departure from average, showing widespread >2" forecast across eastern Colorado. The individual days are shown beneath, and show the rain chances increasing Weds through Sat. Graphic from https://climate.colostate.edu/drought/#outlook

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Colorado Climate Center @climate.colostate.edu · 01/08/2026

Happy 150th birthday, Colorado! Here's one of our favorite maps: average annual precipitation with color shading inspired by the state flag. It nicely illustrates the many variations in weather and climate across our beautiful state. 🎂🥳

Map of annual average precipitation in Colorado, with colors drawn from the state flag. The mountains are in white with over 50" of precipitation; some of the river valleys are in red with less than 10" of precipitation.

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Colorado Climate Center @climate.colostate.edu · 31/07/2026

Today is the 50th anniversary of the Big Thompson flood of July 31, 1976: one of the deadliest disasters in Colorado history. An intense rainstorm led to a rapid flood wave down the canyon where many people were commemorating Colorado's centennial. 144 people lost their lives. #cowx 1/

Photo of a house sitting atop a bridge after having been washed downstream by the Big Thompson flood. Source: https://www.usgs.gov/media/images/big-thompson-canyon-flood-colorado-1976

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Colorado Climate Center @climate.colostate.edu · 09/07/2026

Warm and dry conditions returned to Colorado in June, with several fast-growing fires starting late in the month. June is also the typical peak for severe thunderstorms in Colorado, and this year was no exception. Read more in our monthly climate summary: climate.colostate.edu/monthly_summ...

June 2026
Colorado Monthly Climate Summary
Maximum daily precipitation (5.43"
at Akron)
Minimum daily temperature (21°F at
Jefferson and Hebron)
Flooding in Evergreen on June 24th
109 mph wind gust reported in Akron
Multiple 2"+ hail reports, including near Fort Morgan and Colorado Springs
Multiple major wildfires ignite throughout CO
Maximum daily temperature (106°F
at Pueblo, La Junta, and Ordway)
US Drought Monitor for June 30, 2026
Statewide Temperature and Precipitation Ranks for June 2026 (based on 1895-2026 data)
10th warmest (above average)
17th driest (below average)

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Colorado Climate Center @climate.colostate.edu · 03/07/2026

Wildfires have grown quickly in Colorado in the last week amid dry and windy conditions. We've revamped the interactive maps of large wildfires on our website, to also include currently active fires (updated daily). climate.colostate.edu/large_wildfi... #cowx

Screenshot of the interactive map of wildfires at https://climate.colostate.edu/large_wildfires.php. It shows only the fires larger than 50,000 acres, with the currently active Aspen Acres fire highlighted.

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Colorado Climate Center @climate.colostate.edu · 10/06/2026

It was a pretty normal May across Colorado, which might have felt unusual after all the warmth recently. May concluded the warmest spring on record for Colorado. There was beneficial rainfall (and snowfall!) but drought persisted. More in our May summary: climate.colostate.edu/monthly_summ...

May 2026
Colorado Monthly Climate Summary
Over 2ft of snow falls near Estes Park
Minimum daily temperature (1°F at
Long Draw
Reservoir)
Maximum daily precipitation (2.57"
at Kirk)
Maximum daily snowfall (23.1"
near Allenspark)
4.5" hailstone reported near Last Chance
Maximum daily temperature (97°F at Walsh, Springfield and Lamar)
Sharpe Fire burns 18,000
acres and prompts evacuations in Baca County
US Drought Monitor for May 26, 2026
Statewide Temperature and Precipitation Ranks for May 2026
(based on 1895-2026 data)
36th warmest (above average)
50th driest (near average)
COLORADO CLIMATE
CENTER

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Colorado Climate Center @climate.colostate.edu · 06/06/2026

Critical fire weather in western Colorado each day from today (Saturday) through Tuesday, with hot, dry, and windy conditions. Graphic from NWS Grand Junction (www.weather.gov/media/gjt/Ds...) #cowx

Critical Fire Weather
Today through Tuesday
1. What: Critical fire weather
Low relative humidity and gusty winds are expected
2. When: Today through Tuesday
Each afternoon and early evening
3. Where: Western Colorado and Eastern Utah
Where fuels are critical, which is most locations below 8,000 feet
What's Changed
Graphics have been updated to include the latest forecast. Humidity and wind graphics for Tuesday have been included.
Centered Area: NWS Grand Junction, Co
Fire Weather Conditions
[3] Extremely Critical
Critical
Elevated
Dry Thunderstorm
Coverage
2] Scattered
1 Isolated
OUTDOOR FIRES COULD
QUICKLY SPREAD
National Oceanic and
Atmospheric Administration
U.S. Department of Commerce
AVOID OUTDOOR
BURNING
REPORT FIRES TO LOCAL AUTHORITIES
For more information go to www.weather.gov/git
National Weather Service
Grand Junction, CO

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Colorado Climate Center @climate.colostate.edu · 21/05/2026

🌧️ Models are optimistic about our precipitation chances over the next couple of weeks. The latest 8-14 day outlook from NOAA shows increased likelihood for above average precipitation for the end of May-early June. #cowx

8-14 day precipitation outlook from the NOAA Climate Prediction Center, showing increased odds for above-normal precipitation across CO.

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Colorado Climate Center @climate.colostate.edu · 21/05/2026

🏜️ CO Drought Update: The northern half of CO saw substantial precipitation earlier this week, leading to improvements for some in the latest Drought Monitor. Southern CO saw less moisture, prompting deteriorating drought conditions in the San Luis Valley.

Infographic illustrating Colorado's drought status per the US Drought Monitor. ~96% of the state is currently experiencing drought.

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Colorado Climate Center @climate.colostate.edu · 11/05/2026

After a record-shattering March, April seemed at least a little more normal in Colorado. But it was again warmer than average. Flash drought set in across the eastern Plains. Mountain snowmelt slowed, but remained record low. Read more in our April 2026 summary: climate.colostate.edu/monthly_summ...

April 2026
Colorado Monthly Climate Summary
Hard freeze causes major damage to West Slope fruit crops
70+ car pileup on I-70 during April 14 snow
Maximum daily temperature (94°F at Burlington)
Maximum daily snowfall (12" near Crested Butte)
Flash drought conditions impact the Eastern Plains
Minimum daily temperature (-1°F at Park Reservoir and Lake George)
Maximum daily precipitation (2.9" at Columbine Pass)
Record-low snowpack persists

Statewide Temperature and Precipitation Ranks for April 2026 (based on 1895-2026 data)
13th warmest (above average)
36th driest (below average)

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Colorado Climate Center @climate.colostate.edu · 30/04/2026

🏜️ Colorado Drought Update: It's been a while since we've had drought improvements to report on! A few parts of the state finally saw some beneficial rainfall. Meanwhile, drought conditions continued to worsen in southeast CO as mostly dry conditions persisted. #cowx

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Colorado Climate Center @climate.colostate.edu · 02/04/2026

As a result, the drought situation continues to worsen. Almost the entire northwestern quarter of the state is now in D4 (exceptional) drought, going back to a dry spring and summer in 2025 and a terrible winter and early spring this year. D4 coverage of 21.59% is the largest since February 2021. 4/

US Drought Monitor for March 31, 2026 for Colorado. The entire state has at least D0 (abnormally dry) conditions, with extreme to exceptional drought in most of western Colorado. From https://droughtmonitor.unl.edu/.

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Colorado Climate Center @climate.colostate.edu · 02/04/2026

Perhaps more shocking is how much less SWE there was than in any previous years. Most locations have less than half of the previous record low, and several locations that have never before had less than 5 or 6 inches of SWE on April 1 have no snow on the ground this year. 3/

Map showing the percent of the previous record-low April 1 SWE that was observed on April 1, 2026. Most sites have less than 50% of the previous record low. Locations where the previous record low was zero not shown. Data obtained from USDA/NRCS.

Five snow courses that had a previous record low of more than 4″ of SWE on April 1, and observed zero SWE on April 1, 2026. All of these sites have at least 64 years of observations (Middle Fork Campground has 90 years). Fourteen other sites also reported zero SWE this year and had never previously been snow-free on April 1.
Snow course site
County
Elevation (feet)
Median April 1 SWE (inches)
Previous minimum April 1 SWE (inches)
April 1, 2026 SWE (inches)
Yampa View
Routt
8220
13.8”
6.5” in 2012
0
Middle Fork Campground
Grand
8990
9.9”
5.8” in 1981
0
Ironton Park
Ouray
9610
12.8”
5.2” in 1966
0
Keystone
Gunnison
9950
15.3”
4.4” in 2012
0
Mc Intyre
Larimer
9020
8.8”
4.2” in 1981
0

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Colorado Climate Center @climate.colostate.edu · 02/04/2026

At snow course sites with data for more than 50 years (i.e., including the awful snow years of 1977 and 1981), which year had the lowest snow water equivalent on April 1? At 60 out of 64 sites, it was this year. 2/

Map showing the water year with the lowest April 1 snow water equivalent at snow course sites with more than 50 years of records. Nearly all of them say "2026". Asterisks indicate years where 2026 was tied with one or more other years for record low. Data obtained from USDA/NRCS. Shaded map background is elevation.

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Colorado Climate Center @climate.colostate.edu · 26/03/2026

The latest US Drought Monitor: Last week's record-setting temperatures and dry weather brought widespread worsening drought to Colorado. Nearly a quarter of the state is now seeing extreme drought or worse conditions. #cowx

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Colorado Climate Center @climate.colostate.edu · 23/03/2026

Last week's record-setting heat took a major toll on Colorado's snowpack (which was already in bad shape). We're currently sitting at 44% of average with ~2 weeks to go until our average peak. Little to no precipitation is expected over the next 7 days. #cowx

Colorado statewide snowpack graphic, illustrating the 2026 snowpack relative to historical data. The 2026 data shows a steep drop in snow water equivalent over the past week.

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Colorado Climate Center @climate.colostate.edu · 11/03/2026

Potential for very strong winds and low humidity tomorrow (Thursday) in northern Colorado, which means increased fire danger. Forecast graphic from NWS in Boulder #cowx

NWS graphic "Dry and Windy Thursday", showing peak gusts over 80mph in the Front Range foothills, and humidity below 20% across the eastern plains.

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Colorado Climate Center @climate.colostate.edu · 10/03/2026

And it's also the warmest start to a water year on record; more than 2°F warmer than the previous warmest October through February (1999-2000). In this quadrant chart showing temperature and precipitation from Oct thru Feb, the water year 2026 temperature stands far above all previous years. 3/4

Quadrant chart showing temperature on the vertical axis and precipitation on the horizontal axis, with each October through February period shown for Colorado. 2026 is shown with a star, far above all the other symbols, indicating it was much warmer than any previous October through February period.

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Colorado Climate Center @climate.colostate.edu · 10/03/2026

The warm February closed out the warmest climatological winter in 131 years of records for Colorado; 1.6°F warmer than the previous warmest winter (1980-81). Many locations set records for the most days with high temperatures at or above 60°F in a winter, including Akron shown here. 2/4

Graph showing the number of days with high temperature >= 60F at Akron, Colorado. The previous high was 20; this year had 37.

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Colorado Climate Center @climate.colostate.edu · 10/03/2026

Unfortunately, not much good news to share in our February state climate summary. According to NOAA data, it was the warmest February in 132 years of records. Mountain snowpack remains at the lowest level in over 40 years. Several locations set new monthly high temperature records for February. 1/4

February 2026
Colorado Monthly Climate Summary
statewide departure from 1901-2000 avg: +9.2°F statewide departure from 1991-2020 avg: +7.6°F
statewide rank: 1st warmest/132nd coldest
Warmest February on record statewide
Snowpack remains lowest in over 40 years
Several locations, including Denver, Fort Collins, Akron, and Colorado Springs shatter records for most 60°F+ days
Multiple grass fires, including ones near Boulder, Thornton, Matheson, and Wiggins
Maximum daily precipitation (1.8" at Spud
Mountain)
Minimum daily temperature (-27°F
in Taylor Park)
Maximum daily temperature
(85°F in Pueblo and Campo)
Maximum daily snowfall 12.5" near Bayfield)
February 2026 Temperature Rank (from NCEI nclimgrid)
Statewide Temperature and Precipitation Ranks for February 2026 (based on 1895-2026 data)
1st warmest (record warmest)
37th driest (below average)

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Colorado Climate Center @climate.colostate.edu · 05/03/2026

Drought continues to expand in Colorado, with this week's US Drought Monitor showing a new area of extreme drought (D3) around the Denver metro area and expansion of severe drought (D2) in northeast Colorado, in addition to the ongoing extreme to exceptional drought in the mountains. #cowx

US Drought Monitor for Colorado for March 3, 2026, showing over 56% of the state in drought, and over 10% in extreme drought or worse.

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Colorado Climate Center @climate.colostate.edu · 26/02/2026

Here are some additional locations that saw record-setting warmth on Tuesday 🌡️ #cowx

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Colorado Climate Center @climate.colostate.edu · 13/01/2026

Exceptional. Record-smashing. Disturbingly warm. December 2025 was one for the record books in Colorado. 🌡️ Warmest December 🌡️ >1000 daily high temperature records 🌡️ Warmest October thru December by far 🌡️ 4th-warmest year Read more in our monthly summary: climate.colostate.edu/monthly_summ...

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Colorado Climate Center @climate.colostate.edu · 19/12/2025

Very strong winds and extremely dry conditions are expected across the Front Range tomorrow (Dec. 19). Critical fire weather conditions will be in place, with the greatest risk over parts of Boulder and Jefferson counties. Key messages below from NWS Boulder. Stay safe and weather aware! #cowx

Graphic from National Weather Service in Boulder showing maximum wind gusts for Friday, December 19 with accompanying text:

Particularly Dangerous Situation!!!

Key Messages

Foothills & along CO Highway 93 westward!
Gusts of 85-100 mph possible from Hwy 93
corridor westward
Sustained winds, in the same corridor, of 45-55
MPH.
Relative humidity: 8 to 20 percent
Uncertainty: If the strongest winds make it past
Hwy 93/US 36

Graphic from NWS Boulder showing Red Flag Warnings across the Colorado Front Range and accompanying text reading:

Critical Fire Weather Conditions Friday

Key Messages

Critical Fire Weather Conditions
Wind gusts up to 40 mph east of I-25 mph.
Winds arrive later in the afternoon for I-25
Corridor and adjacent plains.
Relative humidity: 8 to 20 percent
Prolonged warm and dry conditions has cured grasses and brush
Uncertainty: The eastern extent and timing of the 60-100 mph winds from the base of the foothills and extent of stronger 30-40 MPH winds over the eastern portions of the Palmer (The Watch area)

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Colorado Climate Center @climate.colostate.edu · 18/12/2025

Extreme winds were observed across eastern Colorado yesterday, with numerous wildfires growing quickly in Yuma County last night. The strongest winds were in the foothills, with several reports of gusts over 100mph. But the >80mph gusts on the eastern plains are perhaps even more unusual. #cowx

Map of maximum wind gusts from the ASOS, CoAgMET, and Northern Water networks on 17-18 December 2025.

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Colorado Climate Center @climate.colostate.edu · 16/12/2025

Key messages from NWS Boulder's briefing on the upcoming high winds along the Front Range. Available at: www.weather.gov/media/bou/Ds... #cowx

High Impact Wind Event
Increasing confidence in eastward spread of downslope winds
Key Messages
● High confidence in wind gusts 80-90 mph for the
mountains and foothills above 9,000’ (85% chance).
● Medium confidence in wind gusts over 75 mph for
portions of the lower foothills and favored lower
elevations west of I-25 (60% chance).
● Medium-low confidence in wind gusts up to 60
mph across the northern plains Wednesday evening
(50% chance).
● Critical fire weather conditions expected
Wednesday afternoon for the urban corridor
○ Winds can easily overcome marginal RH
values
● Lull in the stronger winds on Thursday, still gusty
35-50 MPH across much of the region and cooler
● Medium confidence for another significant
downslope wind event (50-60% chance) Friday with
drier atmospheric conditions
● Heavier snows expected Wednesday North Park

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Colorado Climate Center @climate.colostate.edu · 12/12/2025

November was the 3rd-warmest on record for Colorado: 7.5°F above the 20th century average for the month. And much of the state was dry, with little snow in either the mountains or at lower elevations. Read more in our November monthly climate summary: climate.colostate.edu/monthly_summ... #cowx

Cover page of the November 2025 Colorado Monthly Climate Summary. It shows the extremes around the state, and that it was the 3rd-warmest and 42nd-driest November out of 131 years of records.

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Colorado Climate Center @climate.colostate.edu · 20/11/2025

For those unfamiliar, CoAgMET is a network of automated weather stations across Colorado, with real-time data as well as information and tools relevant to agriculture, water resources, and more. Visit: coagmet.colostate.edu

Map of high temperatures across Colorado on November 19, 2025, from CoAgMET and the Northern Water weather network. Highs on the eastern plains were in the 60s, and in western Colorado mainly in the 50s. From https://coagmet.colostate.edu

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Colorado Climate Center @climate.colostate.edu · 20/11/2025

Yesterday, we hosted a meeting for partners and stakeholders of CoAgMET, Colorado's Mesonet. We shared the latest updates and plans, heard ideas for how to make the network even better, and visited the unique station setup on the roof of the Hydro building at the CSU Spur campus in Denver.

A classroom full of people watching a presenter, who is discussing a slide showing a CoAgMET weather station

A person points out features of a weather station on the roof of a building, while other people look on.

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Colorado Climate Center @climate.colostate.edu · 13/11/2025

If all this warm and dry November weather has you thinking back to October when there was quite a bit more happening, our monthly summary is for you. Including the big southwest rainstorm and flood, a lack of mountain snow, and more warmth on the Plains: climate.colostate.edu/monthly_summ... #cowx

Front page of the October 2025 Colorado Monthly Climate Summary, with a map of the monthly extremes and notable events. It was the 10th warmest and 46th wettest October.

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Colorado Climate Center @climate.colostate.edu · 12/11/2025

We hope you've been looking up tonight! Here's our view from Fort Collins a little earlier 🌌

2607

Colorado Climate Center @climate.colostate.edu · 03/11/2025

Lots of new daily high temperature records were set across Colorado yesterday, some by more than 5℉! ☀️

Map of daily high temperature records set on November 11, 2025 across Colorado.

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Colorado Climate Center @climate.colostate.edu · 24/10/2025

It's been a busy couple of weeks of drought improvements across Colorado! Here's a recap of what's changed in the past two weeks across the state. 🌧️ And ICYMI, check out our previous post for a summary of the remarkable rainfall that brought these major changes to the Drought Monitor.

Summary graphic titled "October has brought major drought improvements to Colorado". It shows the current US Drought Monitor for Colorado, the US Drought Monitor for Colorado from two weeks ago, and change in the current US Drought Monitor for Colorado over the past two weeks. There are also bullet points on the graphic reading: Recap of the last two weeks:
-21.3% decrease in area experiencing severe drought (D2) or worse conditions
-Three-category drought improvements across parts of the San Juans
-29.2% of the state is still experiencing drought

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Colorado Climate Center @climate.colostate.edu · 17/10/2025

There were major improvements to this week's drought monitor following the significant precipitation and flooding that impacted western CO over the past week. Changes include two-category improvements over portions of southwest CO, many of which are now drought-free. #cowx

Summary graphic titled "Colorado Drought Update". It shows the current US Drought Monitor for Colorado, change in the current US Drought Monitor for Colorado since last week, and percent area of Colorado experiencing drought.

144

Colorado Climate Center @climate.colostate.edu · 10/10/2025

Follow the ongoing rainstorm in southwestern Colorado with CoAgMET: already nearly an inch of rain today near Durango! #cowx coagmet.colostate.edu/maps/precip/...

map of CoAgMET precipitation through 10:50am MT on October 10, with stations near Durango nearing 1"

Time series of precipitation at the Durango CoAgMET station, with 0.99" through 10:55am on October 10.

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Colorado Climate Center @climate.colostate.edu · 07/10/2025

And explore the data yourself with these interactive maps: climate.colostate.edu/normals_stn_...

screenshot from https://climate.colostate.edu/normals_stn_select_freeze.html, showing the interactive map of the median date of the first fall freeze across Colorado.

Graph showing the probability of the first date of reaching various temperatures at Rocky Ford, Colorado. The median date of the first temperature 32 or lower is October 8 at this location.

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Colorado Climate Center @climate.colostate.edu · 02/10/2025

The water year also aligns nicely with patterns in streamflow. It captures the gradual increase in runoff throughout the spring, followed by summertime peak, then the gradual decline in late summer/early fall. [6/7]

A hydrograph showing 7-day average discharge (or streamflow) at a streamgauge site on the Colorado River near Cameo during the water year (Oct-Sep). The lines on the graph generally show gradually increasing streamflow in the spring, peak streamflow in the summer, and then decreasing streamflow in the fall. There is a line for each year of data (1934-2025), and key percentiles are highlighted. POR = period of record (92 years at this site). Data from USGS and NRCS.

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Colorado Climate Center @climate.colostate.edu · 02/10/2025

Starting the water year on Oct 1 means we account for most (if not all) of the winter snowpack. This graph of water year snow water equivalent (SWE) at Fremont Pass shows this well. Look how much water would be unaccounted for during the spring runoff if we only started counting on Jan 1! [5/7]

A graph showing historical snow water equivalent (SWE) from Oct-Sep at Fremont Pass. There are several lines on the graph (such as historical maximum and minimum SWE at that site). All lines generally show increasing SWE from Oct to May, followed by a steep decrease in May-June during the spring melt. Data from NRCS.

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Colorado Climate Center @climate.colostate.edu · 02/10/2025

If you're familiar with Colorado, or even the West more generally, you're probably aware that our winter snowpack is the biggest contributor to our warm season water supply. This snowpack starts to build in the fall (long before the start of the calendar year). [4/7]

View looking towards Emerald Lake in Rocky Mountain National Park in early November 2019. There is deep snow on the ground. Pine trees are scattered across the foreground and there are snow-capped peaks in the background. The sky is mostly clear and sunny.

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Colorado Climate Center @climate.colostate.edu · 02/10/2025

But why begin tracking the movement of water in October? A big reason for offsetting the water year from the calendar year is so that we can properly budget how much winter precipitation will be available for the following runoff season. [3/7]

A river with blocks of snow and ice. There are steep hills with trees on each side of the river, and the sky is partly cloudy.

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Colorado Climate Center @climate.colostate.edu · 25/09/2025

Only some of this precipitation was incorporated in this week's U.S. Drought Monitor (the weekly data cutoff is Tuesdays at 6am MDT). Nonetheless, we still saw some drought improvements throughout the state this week! 🌧️

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Colorado Climate Center @climate.colostate.edu · 24/09/2025

Yesterday was the wettest day in quite some time for northeastern Colorado. Widespread observations of over 1" of rain, and over 2" in some spots on the Plains. Several inches of snow in the mountains too! Map from coagmet.colostate.edu #cowx

Map of precipitation from CoAgMET on September 23, 2025. It shows over 1" of rain across all of northeast Colorado, with a maximum of 2.33" at Akron.

0164

Colorado Climate Center @climate.colostate.edu · 18/09/2025

9/18 Drought Update 🌵: We saw more beneficial precipitation last week, which prompted widespread improvements in western and southern Colorado in this week's US Drought Monitor. Good news for now, but we'll need additional moisture to continue chipping away at those longer-term deficits.

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Colorado Climate Center @climate.colostate.edu · 10/09/2025

August Recap ⏪: Hot, dry conditions intensified drought and fanned wildfires across western Colorado, but monsoon moisture finally delivered some much-needed precipitation at the end of the month. Just how significant was that rainfall? All that and more in our monthly climate summary! col.st/STpEm

A summary flier showing a map of Colorado with the US Drought Monitor overlaid with notable climate statistics August 2025. There is a photo of a waterfall with trees behind the map and text.

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