Grand Junction weather at a glance
Grand Junction sits in a high desert valley at about 4,858 ft. Summers are hot and dry, winters are cold with little snow on the valley floor, and rain is light in every month. The numbers below are 1991 to 2020 normals from the NOAA station at Grand Junction Walker Field, so they describe the valley, not the Grand Mesa or the rim of the canyons.
If you plan to hike in the canyons, the season matters more than anything else on this page. The trails in Colorado National Monument have no water. A guided drive or a morning outing can be easier than a midday walk, and the Colorado National Monument tours page shows what is on offer.
Weather by month
Monthly means of the daily high and low, and total precipitation. NOAA station Grand Junction Walker Field, normals 1991 to 2020.
| Month | Average high | Average low | Precipitation |
|---|---|---|---|
| January | 3.4 °C | -8.2 °C | 15.5 mm |
| February | 8.0 °C | -4.4 °C | 13.5 mm |
| March | 14.6 °C | -0.2 °C | 20.3 mm |
| April | 18.8 °C | 3.4 °C | 24.9 mm |
| May | 24.9 °C | 8.4 °C | 21.1 mm |
| June | 31.8 °C | 13.8 °C | 10.4 mm |
| July | 34.7 °C | 17.7 °C | 15.0 mm |
| August | 32.7 °C | 16.4 °C | 23.4 mm |
| September | 27.6 °C | 11.4 °C | 30.2 mm |
| October | 19.4 °C | 4.2 °C | 25.1 mm |
| November | 11.0 °C | -2.5 °C | 15.5 mm |
| December | 3.8 °C | -7.8 °C | 15.2 mm |
Values are converted from the NOAA tables in °F and inches and rounded to one decimal. Precipitation includes the water content of snow. For most trips, spring and fall are the milder choice. These are the months with highs between roughly 15 and 28 °C. Treat that as a guide, not a guarantee.
Our pick: night sky ride
Clear, dry nights suit this stargazing drive, so check the forecast before you book.
Hand-picked tours, booked through GetYourGuide. Prices are indicative starting prices in US dollars (as of October 2026). Tap a tour for live availability and the current price in your currency.
Tours around Grand Junction
Canyon drives, wine country and Grand Mesa trips, with live prices and availability.
Summer heat in the Colorado National Monument
July is the hottest month, with an average high of 34.7 °C. On some summer days temperatures in the monument can climb above 100 °F (37.8 °C). There is no water on the trails. NPS recommends at least 1 US gallon per person and day, which is about 3.8 liters. Start early, carry extra water and turn around before the heat builds.
Storms need a plan too. Flash floods are most likely from July to September but can happen in any month. If water rises or a storm builds, move to higher ground at once. Stay at least 2 meters from drop-offs, and do not step into the seasonal pools in the canyons, which are drinking places for wildlife.
Best time to visit by activity
A reading of the monthly numbers.
Canyon hikes
April, May, September and October have lower highs than summer. Winter highs are the lowest of the year. See the Colorado National Monument guide for the drive.
Wine and fruit
Late spring and early fall are comfortable for tasting rooms and orchard roads. Peach season runs from late June to early October, with the main weeks from mid-July to August. See Palisade.
Grand Mesa
The Grand Mesa is far higher than the valley, around 11,000 ft, so valley numbers do not apply. Summer and winter there are very different trips. Read the Grand Mesa guide before you go.
Winter driving
On I-70, traction and chain rules can be active from 1 September to 31 May, and severe weather can close the road. Check current signs and your rental contract. More on routes in the Colorado road trip page.
Plan the rest of your trip
Where the weather fits in.
Grand Junction weather: frequently asked questions
What is the hottest month in Grand Junction?
July. The normal high is 34.7 °C (94.5 °F), and the valley has 7.8 days a year with 100 °F or more.
Does it snow in Grand Junction?
Yes, but not much. The normal yearly snowfall is about 45 cm (17.7 in), added up over the winter. That is total snowfall, not a snow cover that stays on the ground.
When is it rainiest?
September has the highest monthly normal at 30.2 mm, followed by October at 25.1 mm and April at 24.9 mm. June is the driest month at 10.4 mm.
What is the best time to visit Grand Junction?
That depends on the plan. Spring and fall are easier for hiking in the canyons than midsummer. Summer suits the Grand Mesa and peach season. Winter suits cross-country skiing on the Grand Mesa.
Do the airport numbers apply to the Grand Mesa?
No. The Grand Mesa lies much higher than the valley station, so its snow, lake and trail conditions differ a lot from the table above.