Nunn, Colorado Weather
Pikas hayfeeding in granite peaks. Day 77 of spring. Read this microseason across nine climate regions →
Nunn weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 3Light Drizzle25%0.01″85°52°—
- ThursdayJun 4Overcast10%—89°51°+4°
- FridayJun 5Mostly Clear10%—87°60°-2°
- SaturdayJun 6Overcast——93°59°+6°
- SundayJun 7Overcast32%—93°57°0°
- MondayJun 8Light Drizzle32%0.04″88°61°-5°
- TuesdayJun 9Overcast23%—96°57°+8°
PM2.5 at 12.4 µg/m³ (AQI 57) with a 0.76 fine-to-coarse ratio and 5 mph wind — combustion smoke trapped in calm air, not road dust. AQI flat over the last 6 hours (within ±3 points).
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 31. Overcast through the UV peak window (cloud cover ~76%) — afternoon ozone should stay flat.
- Present
- AQI 31
- UV peak
- 2.0 at 1 PM
- Sky at peak
- overcast
- Projected peak
- AQI 4
PM × Wind × Precip
PM2.5 at 12.4 µg/m³ (AQI 57) with a 0.76 fine-to-coarse ratio and 5 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.76
- Wind
- light
- 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).
The higher the clouds, the finer the weather.
- Moonrise
- 4:55 AM
- Moonset
- 1:58 PM
- In sign
- ♑︎ Capricorn
Pikas hayfeeding in granite peaks
Nunn at a glance
- Today vs. normal: 15°F below the seasonal normal for this latitude
- Last frost: April 20 (climatological average for this latitude)
- Microseason: Jun 1–5
- Planting window: Harvest spring lettuce before it bolts. Sow heat-tolerant greens.
Right now in the garden
Warm-season window is open
As of June 4, the last spring frost has passed for most years. Transplant tomatoes, peppers, eggplants, basil, and cucurbits (cucumbers, squash, melons) now. Direct-sow beans and corn into warm soil.
SPC Convective Outlook
Storm Prediction Center — Nunn
SPC has placed Nunn in the General Thunderstorms category for severe thunderstorms today.
- TODAYTSTMGeneral Thunderstorms
- TOMORROWTSTMGeneral Thunderstorms
- DAY 3NONENo severe risk
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.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | — | — |
| April | lettuce, peas, spinach, radishes | — |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | tomatoes, peppers, beans, squash | tomatoes, beans, summer squash |
| August | — | tomatoes, beans, summer squash |
| September | fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| October | fall brassicas, garlic (overwinter), carrots | winter squash, tomatoes (last) |
| November | — | — |
| December | — | — |
A year in weather
Nunn's warmest month is July (~71°F mean) and its coldest is December (~27°F). Rainfall peaks in May (2.5 inches) and bottoms out in January (0.3 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 28° | 0.3″ | 1 |
| February | 30° | 0.4″ | 1 |
| March | 38° | 0.8″ | 3 |
| April | 45° | 1.6″ | 4 |
| May | 54° | 2.5″ | 6 |
| June | 64° | 1.9″ | 4 |
| July | 71° | 1.6″ | 4 |
| August | 69° | 1.3″ | 3 |
| September | 60° | 1.1″ | 2 |
| October | 47° | 1.0″ | 3 |
| November | 36° | 0.6″ | 1 |
| December | 27° | 0.3″ | 1 |
Regional context
Nunn's baseline climate, derived from NOAA NCEI 1991-2020 normals at the nearest reporting station, swings from a January mean of 28°F to a July mean of 71°F — a 43°F seasonal arc typical of the mid-latitude bands. Annual precipitation runs about 13.4 inches spread across roughly 34 days with measurable rain or snow each year.
Precipitation runs summer-dominant here: May averages 2.5 inches across 6.2 days with measurable rain, driven mostly by warm-season storms and thunderstorm activity, while January drops to just 0.3 inches across 0.8 rainy days under drier cool-season air. The warm-season-wet rhythm lines Nunn up with places like Pierce, CO, Ault, CO and Wellington, CO, where the May-September stretch delivers the bulk of the year's precipitation.
The frost-sensitive growing window opens around mid-April, when overnight lows reliably clear freezing for cool-season crops like kale, peas, spinach, and parsnips. Heat-loving transplants like tomatoes, peppers, and squash generally hold off for another 10-14 days to clear the last spring frost risk window. The window closes around mid-November, when overnight lows resume dipping below freezing and frost-tender plants need protection or harvest. These dates represent 30-year central tendencies; actual year-to-year variation can shift either bookend by 7-14 days, and local microclimate features within Nunn — cold-air drainage on calm clear nights, slope aspect, distance from any nearby lake or river — can push the practical frost window earlier or later than the regional average.
Similar climates: Pierce, CO, Ault, CO, Wellington, CO, Severance, CO, Eaton, CO.
Frequently asked
- When does it freeze in Nunn?
- Nunn's last spring frost typically falls around mid-April, and the first fall frost arrives around mid-November.
- What is the rainy season in Nunn?
- May is the wettest month with about 2.5 inches of rain on average; the city receives roughly 13 inches annually.
- What is the warmest month in Nunn?
- July is typically warmest, averaging about 71°F.
- What is the coldest month in Nunn?
- December is typically coldest, averaging about 27°F.
- When can I start a vegetable garden in Nunn?
- Cool-season crops (peas, lettuce) can be sown around the last spring frost (mid-April); warm-season crops (tomatoes, peppers) wait until 1–2 weeks after.
- How many rainy days does Nunn get?
- Nunn averages about 34 rainy days per year.
- What hardiness zone is Nunn?
- Nunn's USDA hardiness zone is determined by its lowest average winter temperature; check the USDA's online lookup with the city ZIP for the current zone designation.
Climate
Nunn, Colorado sits in a cold semi-arid climate zone. January means hover near 28°F while July averages 71°F — a 43°F seasonal swing.
Across the year, Nunn receives about 13 inches of precipitation spread over roughly 34 rainy days.
The rhythm of the year is set by latitude (40.7°N), proximity to large water bodies, and elevation — all of which shape what grows here, when frost is likely, and what the weather story looks like day to day.