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Fort Collins, Colorado Weather

Summer heat breaks with monsoon. Day 43 of summer. Read this microseason across nine climate regions →

Fort Collins weather forecast — hour by hour, 7-day outlook, NOAA radar

Fort Collins, CO
Sunday, August 2 at 8:59 AM
76
°
Clear
Feels like
77°
Humidity
42%
Wind
1 mph
Sunrise
11:58 PM
Sunset
2:14 PM
Fort Collins, CO
Hour by hour · 24h
24-Hour ForecastFort Collins, CO: 24-hour forecast. Temperatures range from 67 to 103 degrees Fahrenheit.
L 67°H 103°
Fort Collins, CO
7-day forecast
  1. Today
    Aug 2
    Overcast
    —
    —
    103°62°—
  2. Monday
    Aug 3
    Overcast
    14%
    —
    100°67°-3°
  3. Tuesday
    Aug 4
    Light Drizzle
    —
    —
    83°63°-17°
  4. Wednesday
    Aug 5
    Light Drizzle
    —
    —
    95°65°+12°
  5. Thursday
    Aug 6
    Drizzle
    —
    —
    96°64°+1°
  6. Friday
    Aug 7
    Overcast
    —
    —
    103°74°+7°
  7. Saturday
    Aug 8
    Overcast
    —
    —
    103°76°0°
Fort Collins, CO
Next 24 hours · Mild now
HOT 90°55°83°110°12p6p12a6anow 70°high 103°low 67°
Fort Collins, CO
Anemometer · 24h winds · from true
NESW
From · True
ENE
072° · backing 38°
Direction
ENE
072°
Sustained
1
mph
Gust
4
mph
Peak 24h
15
avg 5 mph
Beaufort · 1 · LIGHT AIR
0
CALM
<1
1
LIGHT AIR
1–3
2
LIGHT BRZ
4–7
3
GENTLE BRZ
8–12
4
MOD BRZ
13–18
5
FRESH BRZ
19–24
6
STRONG BRZ
25–31
7
NEAR GALE
32–38
24h · sust vs gust · mph
avg 5 mph · pk 15 mph @ 2:00p
01020MPHB1B2B3B4B5-21h-18h-15h-12h-9h-6h-3h-24hNOWpk 184SUSTGUST
−24h−18h−12h−6hnow
A whisper of wind — leaves barely shift on the trees.
Fort Collins, CO
Barometer · 24h pressure · mb
STORMRAINCHANGEFAIRDRY9901000101010201030
Pressure · mb
845.1
+2.0 mb in 3h · rising · 24.96 inHg
Now
845.1
mb
3h
+2.0
mb
12h
-7.1
mb
24h
-9.7
mb
Regime · STORM
STORM
RAIN
CHANGE
FAIR
DRY
24h · Pressure · mb
range 841–856
835840845850855860-21h-18h-15h-12h-9h-6h-3h-24hNOW855.7841.1843.5
The low is filling — pressure climbing out of storm territory.
Fort Collins, CO
Air quality
34
AQI
Good
↓-7 in 6h▲Peak ~49 @ 9 PM

AQI 34 (Good), driven by Ozone. AQI down 7 over the last 6 hours (gradual decline). Ozone at AQI 34 now. With UV 4.3 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 20.

OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion during the projected peak around 9 PM.

PM 2.5Good
5.2μg/m³
PM 10Good
5μg/m³
NO₂Good
9μg/m³
OzoneDRIVERModerate
72μg/m³
UV IndexLow
1.3

What's driving it

Ozone × UV × Sky

Ozone at AQI 34 now. With UV 4.3 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 20.

Present
AQI 34
UV peak
4.3 at 1 PM
Sky at peak
clear
Projected peak
AQI 20

PM × Wind × Precip

PM2.5 at 5.2 µg/m³ (AQI 29) with a 0.98 fine-to-coarse ratio and 1 mph wind — combustion smoke trapped in stagnant air, not road dust.

PM2.5/PM10
0.98
Wind
calm
Recent rain
0h in last 6h
Pattern
stagnant smoke

Trends

Seven days of AQI and PM2.5.

Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).

7-DAY AQI TREND50100SUNMONTUEWEDTHUFRISATSUN7-DAY PM2.5 TREND · μg/m³300
Fort Collins, CO
Sky cover · visibility · 24h
Cloud cover
0%
CLEAR
100%0%−24h−18h−12h−6hnow
Visibility
91.5mi
UNLIMITED
185 mi0 mi−24h−18h−12h−6hnow
Earth · GOES-19 ABI
Full Disk · Visible · GeoColor
GOES-19 full disk Visible · GeoColor
True-color daytime, blue/IR sandwich at night
14:59 UTC · Fort Collins, CO · NOAA NESDIS / STAR · up to 10848 px
Continental US · GOES-19 ABI
CONUS Sector · Visible · GeoColor
GOES-19 CONUS Visible · GeoColor
Daytime true-color, blue-light/IR sandwich at night
14:59 UTC · Fort Collins, CO · NOAA NESDIS / STAR · 5-min cadence · up to 10000 px
Fort Collins, CO
Satellite · infrared · animated
Fort Collins, CO
Loading IR frames…
IR · cloud-top temp© RainViewer · Carto
Fort Collins, CO
Almanac · Sunday, August 2
Red sky at night, sailor's delight.
Civil dawn
5:28 AM
Sunrise
11:58 PM
Daylight
14h 16m
Sunset
2:14 PM
Civil dusk
8:46 PM
Planting note
Sow fall peas. Start kale and collard seedlings for fall.
Fort Collins, CO
The moon
Waning Gibbous
84% illuminated
Moonrise
9:45 PM
Moonset
10:08 AM
In sign
♓︎ Pisces
Fort Collins, CO
Microseason
Aug 1–5

Summer heat breaks with monsoon

plant
Jan 159% of the yearDec 31

Read this microseason across nine climate regions →

Fort Collins at a glance

  • Today vs. normal: 14°F above the seasonal normal for this latitude
  • Last frost: April 19 (climatological average for this latitude)
  • Microseason: Aug 1–5
  • Planting window: Sow fall peas. Start kale and collard seedlings for fall.

ZIP codes: 80521, 80524, 80525, 80526, 80528

16-Day Forecast — Fort Collins

  1. Sun103°62°0%
  2. Mon100°67°14%
  3. Tue83°63°6%
  4. Wed95°65°7%
  5. Thu96°64°7%
  6. Fri103°74°4%
  7. Sat103°76°4%
  8. Sun102°76°12%
  9. Mon100°78°20%
  10. Tue99°77°29%
  11. Wed90°70°44%
  12. Thu93°69°39%
  13. Fri100°72°46%
  14. Sat94°68°50%
  15. Sun95°73°52%
  16. Mon98°71°43%

Forecast data from Open-Meteo (CC BY 4.0).

Live wind & temperature near Fort Collins

Right now in the garden

Peak growing season

As of August 2, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.

SPC Convective Outlook

Storm Prediction Center — Fort Collins

SPC includes Fort Collins in the general thunderstorm area tomorrow — no severe risk, but storms are possible.

  • TODAYNONENo severe risk
  • TOMORROWTSTMGeneral Thunderstorms
  • DAY 3TSTMGeneral Thunderstorms

Thunderstorms possible. Not severe, but capable of producing lightning and brief heavy rain.

Source: NOAA / NWS Storm Prediction Center categorical convective outlook. Outlooks are re-issued multiple times per day; this page reflects the most recent SPC polygons covering the city’s coordinates.

Sun & seasons in Fort Collins

Fort Collins sits in Larimer County, where the year’s longest day runs 15h 5m of daylight and its shortest just 9h 16m — a swing of +5h 48m between the June and December solstices. Clocks spring forward on Sunday, March 8, 2026 and fall back on Sunday, November 1, 2026.

Denver, the state’s largest city, lies about 55 miles to the S. The nearest town Fort Collins tracks is Timnath, roughly 6 miles to the E.

Air quality in Fort Collins’s county has held roughly steady since 2020; its cleanest year on record was 2020 (median AQI 49). See the full air-quality history for Fort Collins.

January 1–5: Deep freeze grips the high peaks.January 6–10: Ice thickens on alpine tarns.January 11–15: Springs stir beneath locked earth.January 16–20: Grouse call from the transition zone.January 21–25: First signals of the soil's turning.January 26–31: Stream water crystallizes thick.February 1–5: The year's coldest fortnight begins.February 6–10: East wind carries a subtle promise.February 11–15: Snowmelt springs whisper beneath ice.February 16–20: Red-wing calls rise from the wetlands.February 21–25: Rain begins to trace the snowline upward.February 26–28: Mist gathers in the warming canyons.March 1–5: Grass and trees stir from their sleep.March 6–10: Hibernators break through frozen ground.March 11–15: First blooms open to the spring sun.March 16–20: Mountain bluebirds return to the summits.March 21–25: Spring equinox at the divide.March 26–31: Aspen catkins burst in clusters.April 1–5: Thunderstorms rumble over granite peaks.April 6–10: Swallows and swifts slice the warming sky.April 11–15: Sandhill cranes call through the wetlands.April 16–20: Rainbows arch over the snowfields.April 21–25: New growth explodes across the montane.April 26–30: Last frost yields to summer growth.May 1–5: Wildflowers crest the high meadows.May 6–10: Summer monsoon clouds gather southward.May 11–15: Snowmelt crests toward the divide.May 16–20: High country wildflowers peak.May 21–25: Summer heat accelerates the growing season.May 26–31: Summer settles into the high country.June 1–5: Pikas hayfeeding in granite peaks.June 6–10: Glacier lily carpets the snowmelt.June 11–15: Paintbrush crowns the ridges.June 16–20: Thunderheads build by noon.June 21–25: Long light holds the peaks.June 26–30: Monsoon moisture drifts north.July 1–5: Monsoon storms drench the south.July 6–10: Wind builds through canyons.July 11–15: Lightning crowns every peak.July 16–20: Elk herds claim alpine meadows.July 21–25: Pika caches reach their peak.July 26–31: Monsoon pulses weaken northward.August 1–5: Summer heat breaks with monsoon.August 6–10: First frost creeps to peaks.August 11–15: Cool wind returns from north.August 16–20: Monsoon clouds gather over the peaks.August 21–25: The monsoon breaks into scattered showers.August 26–31: Summer insects thin as autumn wind rises.September 1–5: Elk descend from summer high meadows.September 6–10: Dew crystallizes on high grass at dawn.September 11–15: Hawks begin the long crossing southward.September 16–20: Equinox: darkness claims the high passes.September 21–25: Thunder retreats as the monsoon dies.September 26–30: First frost hardens the high valleys.October 1–5: October: the aspen stands reach their peak.October 6–10: Aspen gold slides downslope with the chill.October 11–15: Snow settles on the high passes.October 16–20: Elk bugling fades as rut nears its end.October 21–25: First hard frost grips the basin.October 26–31: Late rains settle into November patterns.November 1–5: Aspen canopy falls to earth.November 6–10: Granite bones emerge from cover.November 11–15: Earth begins to harden.November 16–20: Bare ranges hold silence.November 21–25: Snow returns to the peaks.November 26–30: North wind strips the landscape.December 1–5: Deep darkness settles over the ranges.December 6–10: Winter locks the high country.December 11–15: Elk withdraw to winter range.December 16–20: Ice thickens across frozen water.December 21–25: Winter solstice — the sun returns.December 26–31: The year closes in silence.🌱February 14 — First skunk-cabbage spathes thaw their way up☀️March 20 — Spring equinox — day and night balance🌸April 5 — Cherry blossoms peak in the parks🐦May 10 — Warbler migration peaks along the coast✨May 25 — First fireflies scout the meadows at dusk🌞June 21 — Summer solstice — longest day🦗July 25 — Peak cicada chorus in the afternoons🌊August 18 — Warmest sea-surface temperatures of the year🍂September 22 — Autumn equinox — the slow turn❄️October 25 — First widespread frost in the suburbs🍁November 10 — Peak leaf color across the Hudson Valley🌙December 21 — Winter solstice — longest night

Microseason · August 1–5

Summer heat breaks with monsoon

Late summer monsoon surge; southern reaches drench under Gulf moisture; northern peaks cool rapidly as monsoon remnants push north.

Day 214 of 365 · Wedge 43 of 72

The solar year drawn as a wheel of 72 five-day windows. Each wedge is one microseason; the four colored arcs mark winter, spring, summer, and autumn; the small icons sit at notable phenological events. The crimson pointer creeps clockwise as the year turns.

Planting calendar

MonthPlantHarvest
January——
February——
March——
Aprillettuce, peas, spinach, radishes—
Maylettuce, peas, spinach, radishes, tomatoes, peppers, beans, squashlettuce, peas, radishes
Junetomatoes, peppers, beans, squashlettuce, peas, radishes
Julytomatoes, peppers, beans, squashtomatoes, beans, summer squash
August—tomatoes, beans, summer squash
Septemberfall brassicas, garlic (overwinter), carrotstomatoes, beans, summer squash
Octoberfall brassicas, garlic (overwinter), carrotswinter squash, tomatoes (last)
November——
December——

A year in weather

Fort Collins's warmest month is July (~73°F mean) and its coldest is December (~31°F). Rainfall peaks in May (2.7 inches) and bottoms out in January (0.4 inches).

MonthMean tempPrecipRainy days
January32°0.4″2
February34°0.5″2
March42°1.3″3
April49°2.1″5
May58°2.7″6
June67°1.9″4
July73°1.6″4
August71°1.4″3
September63°1.4″3
October50°1.3″3
November39°0.7″2
December31°0.5″2

Regional context

Fort Collins's climate, from NOAA NCEI 1991-2020 station normals, pairs 32°F Januarys with 73°F Julys — a 41°F swing. About 15.9 inches of precipitation falls over roughly 37 days a year.

Precipitation in Fort Collins runs summer-dominant: May averages 2.7 inches across 5.8 days of warm-season storms, while January drops to 0.4 inches over 1.6 rainy days of drier cool air. That puts Fort Collins in a summer-convective cohort with places like Timnath, CO, Laporte, CO and Loveland, CO.

The cool-season window in Fort Collins starts at mid-April, when nights stop freezing — think peas, lettuce, spinach, and radishes. In Fort Collins, warm-season transplants — tomatoes, peppers, basil — wait two weeks past Fort Collins's frost date. Fort Collins's window closes around mid-November as overnight lows return below freezing. Within Fort Collins, cold-air pooling chills low spots by 5-10°F, shifting Fort Collins's local frost dates.

Similar climates: Timnath, CO, Laporte, CO, Loveland, CO, Windsor, CO, Severance, CO.

Naturalist notes

Late May brings the return of broad-tailed hummingbirds to Fort Collins gardens and mountain meadows.

Ponderosa pine trees begin releasing their pollen around mid-May, dusting surfaces with yellow powder.

Frequently asked

When does it freeze in Fort Collins?
Fort Collins's last spring frost lands near mid-April, and in Fort Collins the first fall frost follows around mid-November.
What is the rainy season in Fort Collins?
May is the wettest month in Fort Collins, about 2.7 inches on average; the year totals roughly 16 inches.
What is the warmest month in Fort Collins?
On average July tops the year in Fort Collins at about 73°F.
What is the coldest month in Fort Collins?
The coldest stretch in Fort Collins falls in December, around 31°F on average.
When can I start a vegetable garden in Fort Collins?
In Fort Collins, sow peas and hardy greens around mid-April; Fort Collins's tomatoes and peppers wait two weeks more.
How many rainy days does Fort Collins get?
Fort Collins records around 37 days of measurable precipitation annually.
What hardiness zone is Fort Collins?
Since December in Fort Collins averages 31°F, Fort Collins's USDA zone follows that floor — confirm it by ZIP.
What is the 10-day forecast for Fort Collins?
Fort Collins's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
Will it rain this week in Fort Collins?
See this week's day-by-day rain chances for Fort Collins in the daily forecast above, and the next 24 hours in the hourly chart.
What is the weather like right now in Fort Collins?
Current conditions for Fort Collins and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
How often is the Fort Collins forecast updated?
The Fort Collins forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
When are sunrise and sunset in Fort Collins?
Today's sunrise and sunset times for Fort Collins are in the Almanac section above, along with civil dawn, civil dusk, and day length. Day length is longest near the summer solstice and shortest near the winter solstice.
How accurate is the weather forecast for Fort Collins?
The next few days in Fort Collins's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.

Climate

Set in a cold semi-arid zone, Fort Collins, Colorado swings from 32°F in the heart of winter to 73°F at midsummer — a 41°F arc.

Yearly precipitation in Fort Collins totals around 16 inches, spread over about 37 days of rain or snow.

Fort Collins sits at 40.5°N; that 41°F seasonal swing frames planting windows and frost dates across Fort Collins.

All cities in Colorado →

Denver, CO weather →

ZIP codes in Fort Collins

  • 80528
  • 80521
  • 80526
  • 80524
  • 80525
  • 80523
  • 80527
  • 80553

Climate normals from the Open-Meteo Climate API. Köppen approximation from NOAA NCEI U.S. Climate Regions. See methodology for data sources, editorial rules, and corrections. Maintainer: Brian Tighe.