Fort Collins pavement weather data

Last reviewed 2026-07-25. Journalists, researchers, and community groups are welcome to cite any figure on this page with attribution and a link.

The climate figures used across this site come from the NOAA sources listed at the bottom of this page, and the main ones are tabulated here. The main source is NOAA's 1991-2020 climate normals for station USC00053005, named FORT COLLINS, CO US in the data service, at 1,525.2 meters on the Colorado State University campus. The Colorado Climate Center at CSU says the station's daily records are complete back to January 1, 1889. Two other normals stations inside a box drawn around Fort Collins, Loveland, Windsor and Wellington add the edges of the area: Fort Collins 4 E and Loveland 2 N.

NOAA publishes annual and seasonal values in tenths, so a raw 1468 is 146.8 days. On this site a freeze-thaw day is one whose minimum drops to 32 degrees or lower while its maximum climbs above 32, so the yearly count equals freezing nights less the days that stay frozen from start to finish. Soil, street and population figures come from the NRCS, the county street standards, the city and the census, and the main sources are listed at the bottom of this page.

Freeze-thaw by season on the campus record

The annual count subtracts one NOAA field from another: 146.8 days a year whose minimum is 32 degrees or lower, less 16.2 days whose maximum never rises above 32. Winter carries more than half of the result. NOAA's seasonal file has no spring value for days that stay frozen, so the spring figure below is the annual value minus winter, summer and fall; it is small either way, since nearly all of the frozen days fall in winter.

NOAA NCEI 1991-2020 annual and seasonal normals, station USC00053005, TMIN-AVGNDS-LSTH032 and TMAX-AVGNDS-LSTH032. Spring frozen days derived by subtraction.

Month by month: freeze-thaw, snow and cool nights

The monthly normals show when each kind of stress arrives. Freeze-thaw days peak in December and January, snow peaks in March, and nights cool enough to slow sealer, at 50 degrees or below, hold on through May and come back in September. NOAA computes the monthly normals separately from the annual ones, so the twelve months do not add exactly to the annual totals above: the monthly freeze-thaw column sums to about 135 and the monthly snow column to 51.4 inches.

NOAA NCEI 1991-2020 monthly normals, station USC00053005. Freeze-thaw days are MLY-TMIN-AVGNDS-LSTH032 minus MLY-TMAX-AVGNDS-LSTH032.

Campus, east side and Loveland compared

Three stations in and near the city have 1991-2020 normals, and they do not agree. The campus reading is the mildest at night. The Fort Collins 4 E station east of campus and the Loveland 2 N station north of Loveland record more freezing nights and, in Loveland's case, a shorter freeze-free season. Drives at the edges of the area are better planned against the colder figures.

Freeze-thaw days are nights at or below 32 F minus days with a high at or below 32 F (16.2, 21.4 and 17.8). Annual precipitation normals: 16.10, 14.97 and 15.76 inches.

Rain, storms and where runoff goes

Precipitation on campus averages 16.10 inches a year, and spring, not summer, is the wettest season at 6.08 inches, against 5.48 in summer, 3.24 in fall and 1.30 in winter. May is the wettest single month at 2.72 inches on the monthly normals. Heavy days are few: 8.7 a year bring half an inch or more and 2.3 bring an inch. The exception on record came in late July 1997, when 10 to 14 inches fell over about 31 hours and flooded the city; the Community Collaborative Rain, Hail and Snow Network began at the Colorado Climate Center at CSU the next year, partly because of that flood.

Runoff from pavement enters a stormwater system the city has run as a utility since 1980, and most of it reaches creeks and the Cache la Poudre River untreated. The Poudre runs 126 miles from Poudre Lake in Rocky Mountain National Park to the South Platte east of Greeley, and 76 miles of it were designated Wild and Scenic on October 30, 1986. Colorado's hail season runs from about mid-April to mid-August, with seven to nine hail days a year across the region, according to a 2018 Denver7 report.

Ground, growth and street standards

The two soil series most often met around the city differ sharply in clay and drainage. Growth has put much of the newest pavement in the surrounding towns, and the county street standards govern what happens at the curb.

LCUASS is the Larimer County Urban Area Street Standards, effective August 1, 2021.

Sources & Methodology

Every figure above was taken from the primary sources below (accessed 2026-07-25). Where a number is derived (arithmetic on published figures) or covers a broader period or area, the text says so.

1. NOAA NCEI 1991-2020 annual and seasonal normals, Fort Collins (USC00053005) — Values in tenths: ANN-TMIN-AVGNDS-LSTH032 1468 (146.8 days), ANN-TMAX-AVGNDS-LSTH032 162 (16.2), ANN-SNOW-NORMAL 558 (55.8 in), ANN-PRCP-NORMAL 1610 (16.10 in), seasonal counts, and freeze dates PRBLST and PRBFST T32FP50 of 05/01 and 10/06.
2. NOAA NCEI 1991-2020 monthly normals, Fort Collins (USC00053005) — Monthly nights at or below 50 F and normal highs and lows. The monthly freeze counts, snow and precipitation came from the same dataset with other data types.
3. NOAA NCEI 1991-2020 normals, Fort Collins 4 E (USC00053006) — Elevation 1499.6 m; 163.9 nights at or below 32 F, 21.4 days at or below 32 F, 47.2 in snow, 14.97 in precipitation, freeze dates 05/03 and 10/04.
4. NOAA NCEI 1991-2020 normals, Loveland 2 N (USC00055236) — Elevation 1548.4 m; 181.1 nights at or below 32 F, 17.8 days at or below 32 F, 41.0 in snow, 15.76 in precipitation, freeze dates 05/10 and 09/28.
5. Colorado Climate Center, Fort Collins weather station description — Complete daily records since January 1, 1889; station just northwest of the Lory Student Center on the CSU campus.
6. USDA NRCS Official Series Description, FORT COLLINS series — Typical pedon north of LaPorte Avenue on North Shields Street; 18 to 35 percent clay in the argillic horizon; well drained; carbonates at 8 to 20 inches.
7. USDA NRCS Official Series Description, NUNN series — Fine, smectitic Aridic Argiustolls; 35 to 50 percent clay; moderately slow or slow permeability; type location in Larimer County.
8. Larimer County Urban Area Street Standards, Chapter 9 — Sections 9.1.2 (permit before any access is built or rebuilt), 9.3.7 (12 to 24 ft approaches, 30 ft for three-car garages), 9.4.4 (8 percent grade within 20 ft) and 9.4.6 (concrete in the right-of-way).
9. City of Fort Collins, Stormwater — Stormwater utility established in 1980; most stormwater flows to local creeks and the Poudre without treatment.