Photo: Citycommunications at English Wikipedia · CC BY 3.0Fort Collins is drier than 93% of U.S. towns: 15 inches of precipitation a year
Deep winter brings January lows near 16°. Its January nights bite harder than in 81% of U.S. towns. Warming shows here too: 2.2° more than in 1901–2000, led by March. Central heating does most of its work from October to April, in months below 50° on average.
A year in Fort Collins at a glance
Each month’s typical high and low, and what it brings.
What stands out about Fort Collins’ climate
Compared with towns across the U.S., with Fort Collins’ place in Colorado beside it.
What a year in Fort Collins feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 154 frost-free days a year
In half of years the last 32° night comes by May 3 and the first by October 6. Day counts come from NOAA’s station at Ft Collins, CO, 2.2 miles from the city’s center point, at about the same height; frost dates and degree days from Ft Collins 4 E, CO, 2.9 miles away.
The 2023 USDA map puts Fort Collins’ center in zone 5b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −11°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 49 inches of snow a winter
Snow, measured at Fcl, CO, falls mostly in March and December. Precipitation (rain plus melted snow) adds up to 15 inches a year; May is the wettest month and January the driest. Rain or snow falls on about 80 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Fort Collins
91% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Ft Collins 4 E, CO.
Living with Fort Collins’ climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
154 frost-free days in zone 5b. The last frost comes by May 3 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Oct 6.
Months with highs of 62–84° and lows of 40° or more: May, June and September. 117 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Fort Collins from natural hazards, river flooding is the largest share (40%); heat waves, cold waves, winter storms and ice storms together are 23%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Fort Collins and its neighbors
Windsor the hottest July afternoons (90°, 1° warmer). Differences under a degree are within what the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Fort Collins’, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Fort Collins, CO | 16° | 89° | 15" | 49" |
| Billings, MT | 15° | 89° | 14" | 48" |
| Preston, ID | 14° | 89° | 15" | 52" |
| Hyde Park, UT | 14° | 89° | 16" | 44" |
| Spring Creek, NV | 15° | 89° | 14" | 41" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Fort Collins averaged 2.2° warmer than the 1900s. The biggest change is in March (+4.3°).
A bigger shift than in 96% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods. In a city of 172,000 people, part of the change is the city itself: pavement and buildings hold heat (the urban heat island).
How Fort Collins compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Fort Collins’ place among Colorado’s.
Fort Collins weather by month
Highs, lows and precipitation from NOAA’s grid at Fort Collins’ center; snow, wet days and snow on the ground from Fcl, CO. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 44° | 16° | 0.4" | 6.0" | 4 | 13 | 21° – 36° |
| February | 46° | 18° | 0.5" | 7.8" | 6 | 11 | 27° – 39° |
| March | 56° | 26° | 1.1" | 8.9" | 6 | 5 | 34° – 49° |
| April | 63° | 33° | 2.0" | 6.3" | 8 | 2 | 42° – 54° |
| May | 72° | 43° | 2.5" | 1.4" | 11 | 1 | 51° – 61° |
| June | 83° | 51° | 1.8" | 0.0" | 8 | 0 | 62° – 73° |
| July | 89° | 58° | 1.6" | 0.0" | 9 | 0 | 68° – 77° |
| August | 87° | 55° | 1.4" | 0.0" | 8 | 0 | 66° – 74° |
| September | 79° | 47° | 1.3" | 0.2" | 7 | 0 | 58° – 67° |
| October | 65° | 34° | 1.1" | 3.8" | 6 | 2 | 42° – 56° |
| November | 52° | 24° | 0.7" | 6.2" | 4 | 5 | 30° – 44° |
| December | 44° | 16° | 0.4" | 8.7" | 4 | 14 | 23° – 35° |
| Year | 65° | 35° | 14.7" | 49.3" | 80 | 52 |
How much a month can swing
A normal is an average. January swings the most: from 1991 to 2020 its average ranged from 21° to 36°. August is the most reliable, staying within 8°.
Where Fort Collins’ numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Fort Collins’ center.
- Snow: Fcl, CO.
- Frost dates, heating and cooling: Ft Collins 4 E, CO, 2.9 miles away.
- Freezing nights, 90° and 100° days: Ft Collins, CO, 2.2 miles from the city’s center point, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Fort Collins’ climate
What is the weather like in Fort Collins?
A typical July afternoon reaches 89°, a January night drops to 16°, and about 49 inches of snow falls in a normal winter. Colder January nights than 81% of U.S. towns; hotter July afternoons than 73% of U.S. towns.
How cold does it get in Fort Collins in winter?
January nights average 16°. About 150 nights a year reach 32° or below and 4 reach 0° or below. In the coldest January of the last 30 years the month averaged 21°.
How much snow does Fort Collins get?
About 49 inches in a normal winter at Fcl, CO, most of it in March and December, with snow on the ground about 52 days a year.
How hot does it get in Fort Collins?
July, with a typical high of 89° and a low of 58°. About 30 days a year reach 90° (Ft Collins 4 E, CO).
When is the first and last frost in Fort Collins?
In half of years the last spring frost (32°) comes by May 3 and the first fall frost by October 6, about 154 frost-free days, at Ft Collins 4 E, CO.
What growing zone is Fort Collins in?
Zone 5b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −11°.
What is the best time of year to visit Fort Collins?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Fort Collins getting warmer?
Yes: 1991–2020 averaged 2.2° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 96% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Fort Collins.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.