Grand Junction, Colorado Weather
Thunder retreats as the monsoon dies. Day 93 of summer. Read this microseason across nine climate regions →
Grand Junction weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 8:22 AM MDT · Open-Meteo
- TodaySep 21Overcast later——83°51°—
- TuesdaySep 22Clear45%—85°60°+2°
- WednesdaySep 23Overcast45%—76°57°-9°
- ThursdaySep 24Overcast——81°61°+5°
- FridaySep 25Drizzle22%0.02″76°64°-5°
- SaturdaySep 26Partly Cloudy13%—82°61°+6°
- SundaySep 27Partly Cloudy13%—86°65°+4°
Air quality now AQI 26 · Good
AQI 26 (Good), driven by PM2.5. AQI projected to climb to 54 over the next 6 hours. PM2.5 at 5.1 µg/m³ (AQI 28), ratio 0.69 with 10 mph wind — characteristic of long-range haze transport rather than a local source.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion during the projected peak around 8 PM.
What's driving it
PM × Wind × Precip
PM2.5 at 5.1 µg/m³ (AQI 28), ratio 0.69 with 10 mph wind — characteristic of long-range haze transport rather than a local source.
- PM2.5/PM10
- 0.69
- Wind
- breezy
- Recent rain
- 0h in last 6h
- Pattern
- transport
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).
September dries up ditches or breaks down bridges.
- Moonrise
- 4:46 PM
- Moonset
- 1:41 AM
- In sign
- ♑︎ Capricorn
Thunder retreats as the monsoon dies
Read this microseason across nine climate regions →
All 72 microseasons on the year wheel →
Grand Junction at a glance
- Today vs. normal: Today averages 67°F (high 83°F, low 51°F), 3°F above the 64°F normal for Sep 21
- Last frost: April 14 (1991–2020 median, NOAA station 5 km away)
- Microseason: Sep 21–25
- Planting calendar: September — plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, winter squash
16-Day Forecast — Grand Junction
- Mon83°51°2%
- Tue85°60°45%
- Wed76°57°45%
- Thu81°61°7%
- Fri76°64°22%
- Sat82°61°13%
- Sun86°65°13%
- Mon78°59°34%
- Tue78°60°17%
- Wed82°60°9%
- Thu84°62°11%
- Fri84°65°19%
- Sat77°63°29%
- Sun78°60°19%
- Mon79°57°13%
- Tue75°56°5%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Grand Junction
Interactive wind and temperature map centered on Grand Junction — it loads in your browser. Open the full weather map.
Right now in the garden
Fall planting + final harvests
As of September 21, the season's first frost (typically October 23) is approaching. Pick what frost-tender plants still carry before the next cold front. This city's planting calendar for September: plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, and winter squash.
SPC Convective Outlook
Storm Prediction Center — Grand Junction
SPC includes Grand Junction in the general thunderstorm area tomorrow — no severe risk, but storms are possible.
- TODAYNONENo severe risk
- 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.
Sun & seasons in Grand Junction
Grand Junction sits in Mesa County, where the year’s longest day runs 14h 55m of daylight and its shortest just 9h 25m — a swing of +5h 30m 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 202 miles to the ENE. The nearest town Grand Junction tracks is Pagosa Springs, roughly 151 miles to the SE.
Air quality in Grand Junction
Air quality in Grand Junction’s county has trended dirtier since 2020; its cleanest year on record was 2020 (median AQI 44). See the full air-quality history for Grand Junction.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| March | lettuce, peas, spinach, radishes | — |
| April | lettuce, peas, spinach, radishes | radishes |
| May | tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, spinach |
| July | tomatoes, peppers, beans, squash | tomatoes, peppers, beans, summer squash, garlic |
| August | beans, squash, fall brassicas, carrots | tomatoes, peppers, beans, summer squash, winter squash |
| September | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash |
| October | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash, fall brassicas, carrots |
| November | — | fall brassicas, carrots |
A year in weather
In Grand Junction, July runs warmest near 79°F and January coldest around 28°F, while September is the wettest month (1.2 inches) and June the driest (0.4 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 28° | 0.6″ | 6 |
| February | 35° | 0.5″ | 6 |
| March | 45° | 0.8″ | 7 |
| April | 52° | 1.0″ | 7 |
| May | 62° | 0.8″ | 6 |
| June | 73° | 0.4″ | 3 |
| July | 79° | 0.6″ | 5 |
| August | 76° | 0.9″ | 7 |
| September | 67° | 1.2″ | 7 |
| October | 53° | 1.0″ | 6 |
| November | 40° | 0.6″ | 5 |
| December | 28° | 0.6″ | 6 |
Regional context
Similar climates Orchard Mesa, CO, Fruitvale, CO, Redlands, CO
In Grand Junction, NOAA NCEI 1991-2020 normals put January near 28°F and July near 79°F — a 52°F seasonal arc — with about 9.1 inches of precipitation over 72 rainy or snowy days.
No season owns Grand Junction's rain: September reaches 1.2 inches across 6.5 days and June keeps 0.4 inches on 3.4, an even spread through Grand Junction's year. It is a balanced pattern Grand Junction shares with places like Orchard Mesa, CO, Fruitvale, CO and Redlands, CO.
Around April 14, Grand Junction sheds its freezing nights — kale, peas, spinach, and parsnips go into Grand Junction's beds. Heat-demanding starts go out a fortnight on in Grand Junction, after the soil warms and cold snaps clear. Frost returns to Grand Junction near October 23, ending the tender-crop season. Open lawns in Grand Junction whiten first when frost returns.
Similar climates: Orchard Mesa, CO, Fruitvale, CO, Redlands, CO, Clifton, CO, Fruita, CO.
Frequently asked
- When does it freeze in Grand Junction?
- Grand Junction's last spring frost lands near April 14, and in Grand Junction the first fall frost follows around October 23.
- What is the rainy season in Grand Junction?
- Grand Junction sees its heaviest rain in September (around 1.2 inches), part of roughly 9 inches a year.
- What is the warmest month in Grand Junction?
- July is Grand Junction's warmest month, averaging about 79°F.
- What is the coldest month in Grand Junction?
- Grand Junction bottoms out in January, with a mean near 28°F.
- When can I start a vegetable garden in Grand Junction?
- Grand Junction's last frost (April 14) cues hardy greens; in Grand Junction, hold heat-lovers two weeks past.
- How many rainy days does Grand Junction get?
- Grand Junction records around 72 days of measurable precipitation annually.
- What hardiness zone is Grand Junction?
- Grand Junction's hardiness zone tracks its winter low; with January near 28°F, check the USDA ZIP map for the exact zone.
- What is the 10-day forecast for Grand Junction?
- Grand Junction'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 Grand Junction?
- See this week's day-by-day rain chances for Grand Junction in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Grand Junction?
- Current conditions for Grand Junction and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Grand Junction forecast updated?
- The Grand Junction forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Grand Junction?
- Today's sunrise and sunset times for Grand Junction 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 Grand Junction?
- The next few days in Grand Junction's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Grand Junction sits at 39.1°N; its climate zone is hot desert (Köppen approximation).
ZIP codes in Grand Junction
- 81501
- 81502
- 81503
- 81504
- 81505
- 81506
- 81507