Your nature year
Fort Collins, Coloradothrough the year
Also for Greeley, CO, Loveland, CO, Windsor, CO: the same nearby places.
When do frost, green-up and fall color come to Fort Collins?
Frost usually lets go around May 2 and comes back around Oct 7, according to the Ft Collins weather station (2.2 mi): roughly 158 days without it. The USA-NPN spring index puts first leaf here around Mar 27 and first bloom around May 5. About 6 weeks pass between first leaf and first bloom here. Head southwest for the closest of the 3 places we follow around Fort Collins. For a day trip, Rocky Mountain is 27 miles off; its fall foliage is Sep 1–Oct 31 (local timing). Rocky Mountain (27 mi) is the pick for wildflowers, May 21–Aug 10 (local timing). Statewide, Colorado's fall color is usually well under way by mid-October.
Updated Sep 28. Sources: US Census Bureau, 2024 Gazetteer (places) ↗ (opens in a new tab), US Census Bureau, city and town population estimates, 2024 ↗ (opens in a new tab), NOAA NCEI U.S. Climate Normals 1991–2020 (annual/seasonal) ↗ (opens in a new tab)
Fort Collins's year at a glance
- Frost possible
- Frost-free, ~May 2 to ~Oct 7
- First leaf ~Mar 27
- First bloom ~May 5
- Fall color under way ~Oct 11 (CO)
- Today
Near Fort Collins right now
- Fall color is usually well under way by mid-October in ColoradoStatewide · USA-NPN volunteer observations, 2020–2025 · not a forecast~13 days
- First fall frost usually around Oct 7 · last spring frost around May 2NOAA 1991–2020 normals, Ft Collins (2.2 mi, 50% dates)~9 days
- Rocky Mountain · 27 mi · Local timing: Sep 1–Oct 31Fall foliage · in its window now
- Guanella Pass · 74 mi · Regional timing: Sep 1–30Fall foliage · in its window now
- Wildflowers · Rocky Mountain · 27 miLocal timing: May 21–Aug 10~8 months
Fort Collins's nature year
- Spring green-upMar
- Wildflowers · Rocky MountainMay–Aug
- Last spring frostMay
- Fall color (CO)Oct
- First fall frostOct
Nearby, season by season
Fall foliage
- Rocky Mountain · 27 miLocal timing: Sep 1–Oct 31
- Guanella Pass · 74 miRegional timing: Sep 1–30
- Maroon Bells · 141 miusually Sep 21–30
Wildflowers
- Rocky Mountain · 27 miLocal timing: May 21–Aug 10~8 months
- Guanella Pass · 74 miLocal timing: Jun 15–Aug 10~9 months
Snow in Fort Collins
Snow usually becomes possible around Nov 7 (our calculation from NOAA's daily snow chances: the first day the chance of 0.1" or more of snow reaches 10%). NOAA's normals at Ft Collins (2.2 mi away): 51 inches of snow in an average year, about 14.4 days with 1 inch or more.
NOAA's chance of at least 0.1 inch of snow on each date (one value per week, September to May), averaged over 1991–2020. A typical year, not a forecast.
Frost and green-up
Last spring frost
May 2
Average (50% date)
First fall frost
Oct 7
About 158 days without frost between
Spring green-up
Mar 27
First bloom around May 5
Frost: NOAA 1991–2020 climate normals at Ft Collins (2.2 mi from Fort Collins), the day a 32 °F night is as likely as not. Green-up: the USA-NPN Spring Index, 1991–2020 average at the town.
Questions people ask
When is the first frost in Fort Collins?
On average around Oct 7, and the last spring frost around May 2: about 158 days without frost between. These are NOAA's 1991–2020 normals at Ft Collins, 2.2 miles away (the day a 32 °F night is as likely as not).
When does spring green-up reach Fort Collins?
The USA-NPN Spring Index puts first leaf around Mar 27 and first bloom around May 5, on average for 1991–2020 at the town.
Where can I see fall foliage near Fort Collins?
Rocky Mountain, 27 miles (local timing: Sep 1–Oct 31); Guanella Pass, 74 miles (regional timing: Sep 1–30); Maroon Bells, 141 miles (usually Sep 21–30). Distances are straight-line.
Where can I see wildflowers near Fort Collins?
Rocky Mountain, 27 miles (local timing: May 21–Aug 10); Guanella Pass, 74 miles (local timing: Jun 15–Aug 10). Distances are straight-line.
When does it start snowing in Fort Collins?
Snow usually becomes possible around Nov 7: our calculation from NOAA's daily snow chances: the first day the chance of 0.1" or more of snow reaches 10%, at Ft Collins. An average year brings 51 inches (NOAA 1991–2020). A typical year, not a forecast.Sources: NOAA NCEI U.S. Climate Normals 1991–2020 (annual/seasonal snowfall) ↗ (opens in a new tab), NOAA NCEI U.S. Climate Normals 1991–2020 (daily snowfall probabilities) ↗ (opens in a new tab)
How we know
US Census Bureau, 2024 Gazetteer (places) (opens in a new tab) (Sep 27) · US Census Bureau, city and town population estimates, 2024 (opens in a new tab) (Sep 27) · NOAA NCEI U.S. Climate Normals 1991–2020 (annual/seasonal) (opens in a new tab) (Sep 27) · USA National Phenology Network, Spring Index 1991–2020 averages (opens in a new tab) (Sep 27) · USA National Phenology Network, colored leaves observations (opens in a new tab) (Sep 28)