The best times to visit Great Falls for ideal weather are

June 11th to September 30th

based on average temperature and humidity from NOAA (the National Oceanic and Atmospheric Administration). Read below for more weather and travel details.

 

 


Other Great Falls Travel Info

Weather in Great Falls

Temperature

Average temperatures in Great Falls vary drastically. Considering humidity, temperatures feel cold for about half of the year and otherwise nice with a low chance of precipitation most of the year. The area is less temperate than some — in the 39th percentile for pleasant weather — compared to tourist destinations worldwide. Weeks with ideal weather are listed above. If you’re looking for the very warmest time to visit Great Falls, the hottest months are July, August, and then June. See average monthly temperatures below. The warmest time of year is generally mid July where highs are regularly around 89.7°F (32.1°C) with temperatures rarely dropping below 53.5°F (11.9°C) at night.

Great Falls Temperatures (Fahrenheit)

Key
High
Average
Low

Great Falls Temperatures (Celsius)

Key
High
Average
Low

“Feels-Like” Temperatures

The way we experience weather isn’t all about temperature. Higher temperatures affect us much more at higher humidity, and colder temperatures feel piercing with high winds. Our perceived temperatures factor in humidity and wind chill to better represent how hot or cold the day feels to a person.

Great Falls Perceived Temperature (F)

Key
High
Average
Low

Great Falls Perceived Temperature (C)

Key
High
Average
Low

 

Average Great Falls Temperatures by Month

Daily highs (averaged for the month) usually give the best indication of the weather. A significantly lower mean and low generally just means it gets colder at night.

Show Fahrenheit

Month Avg. High (°F) Avg. Mean (°F) Avg. Low (°F)
Jan 38 27.2 17.7
Feb 37.7 26.4 16.9
Mar 50.4 36.6 25.8
Apr 56.6 42.1 30.1
May 65.5 51.4 38.4
Jun 75.2 60.3 45.8
Jul 87.8 70.2 52.9
Aug 86.1 68.3 51.5
Sep 76.6 59 44.2
Oct 60.5 46.6 35.6
Nov 46 34.7 24.9
Dec 34.5 24.8 15.1

Show Celsius

Month Avg. High (°C) Avg. Mean (°C) Avg. Low (°C)
Jan 3.3 -2.7 -7.9
Feb 3.2 -3.1 -8.4
Mar 10.2 2.6 -3.4
Apr 13.7 5.6 -1.1
May 18.6 10.8 3.6
Jun 24 15.7 7.7
Jul 31 21.2 11.6
Aug 30.1 20.2 10.8
Sep 24.8 15 6.8
Oct 15.8 8.1 2
Nov 7.8 1.5 -3.9
Dec 1.4 -4 -9.4

 


 

Precipitation (Rain or Snow)

If dry weather is what you’re after, the months with the lowest chance of significant precipitation in Great Falls are March, January, and then August. Note that we define “significant precipitation” as .1 inches or more in this section. The lowest chance of rain or snow occurs around late June. For example, on the week of June 25th there are no days of precipitation on average. By contrast, it’s most likely to rain or snow in late May with an average of 3 days of significant precipitation the week of May 21st.

When can you find snow in Great Falls? Weather stations report very large amounts of snow likely to be deepest around May, especially close to early May. The best time to ski (if at all) in Great Falls is often around around June 11th when fresh powder is deepest. Please note that a value of 0 for snow in the graph below may either mean there was no snow, or that snow is unreported.

Chance of Precipitation

The graph below shows the % chance of rainy and snowy days in Great Falls.

Key
Days with precipitation

Snow on the Ground

The graph below shows the average snow on the ground in Great Falls (in).

Key
Snow depth

Average Rain and Snow by Month

Show Inches

Month Daily Chance of Rain Average Snow Depth (in) Total Precipitation (in)
Jan 8% 4.6 0.8
Feb 11% 3.4 0.8
Mar 5% 2.6 0.6
Apr 19% 2.9 2.2
May 26% 6.2 2.7
Jun 18% 5.9 2.2
Jul 10% 0 1.3
Aug 8% 0 1.2
Sep 11% 0 1.3
Oct 11% 2.3 1.2
Nov 10% 3.8 0.9
Dec 10% 3.6 0.9

Show Centimeters

Month Daily Chance of Rain Average Snow Depth (cm) Total Precipitation (cm)
Jan 8 11.7 2
Feb 11 8.6 2
Mar 5 6.6 1.5
Apr 19 7.4 5.6
May 26 15.7 6.9
Jun 18 15 5.6
Jul 10 0 3.3
Aug 8 0 3
Sep 11 0 3.3
Oct 11 5.8 3
Nov 10 9.7 2.3
Dec 10 9.1 2.3

 

Humidity and Wind

Great Falls has some comfortably humid months, and slightly dry months in the opposite season. The least humid month is August (30.9% relative humidity), and the most humid month is February (55.8%).

Wind in Great Falls is usually moderate. The windiest month is January, followed by November and December. January’s average wind speed of around 12.4 knots (14.3 MPH or 23 KPH) is considered “a moderate breeze.” Maximum sustained winds (the highest speed for the day lasting more than a few moments) are at their highest in early to mid March where average top sustained speeds reach 21.8 knots, which is considered a fresh breeze.

Relative Humidity (%)

The graph below shows the average % humidity by month in Great Falls.

Key
Avg. Relative Humidity

Wind

The graph below shows wind speed (max and average) in knots.

Key
Max Sustained Wind
Average Daily Wind

Average Wind Speeds

Show Wind Speeds

All wind speeds are in knots. 1 knot = 1.15 MPH or 1.85 KPH.

Month Avg. Wind Avg. Wind Feel Sustained High Wind High Wind Feel
Jan 12.4 Significant breeze 20.3 Strong breeze
Feb 9.8 Gentle breeze 17.1 Strong breeze
Mar 10.9 Gentle breeze 19.6 Strong breeze
Apr 9.8 Gentle breeze 18.4 Strong breeze
May 8.5 Gentle breeze 16.8 Strong breeze
Jun 8 Gentle breeze 16.2 Significant breeze
Jul 7.5 Gentle breeze 15.9 Strong breeze
Aug 7.6 Gentle breeze 16.7 Significant breeze
Sep 8.1 Gentle breeze 15.9 Strong breeze
Oct 9.8 Gentle breeze 17.4 Strong breeze
Nov 11.6 Significant breeze 19.7 Strong breeze
Dec 11.5 Significant breeze 19.4 Strong breeze

Show Relative Humidity by Month

Month Avg. Relative Humidity
Jan 49.2%
Feb 55.8%
Mar 43.8%
Apr 43.4%
May 46.7%
Jun 44.2%
Jul 32.3%
Aug 30.9%
Sep 37.2%
Oct 45.7%
Nov 46.8%
Dec 54.4%

 

Is it Safe to Travel to Great Falls?

Our best data indicates this area is generally safe. As of Dec 04, 2023 there are no travel advisories or warnings for the United States; exercise normal security precautions. Check this page for any recent changes or regions to avoid: Travel Advice and Advisories. This advisory was last updated on Dec 04, 2023.


 

The Busiest and Least Crowded Months

The busiest month for tourism in Great Falls, MT, US is July, followed by June and August. Prices for hotels and flights will be most expensive during these months, though you can save if you purchase well in advance. Tourists are unlikely to visit Great Falls in December. Those willing to visit at these times will likely find it the least expensive month.

Estimated Tourism by Month

 

Most Popular Months to Visit

Key
Tourists Seeking Accommodations

Tourism graph is based on Google searches for services used by tourists relative to the rest of the year. Tourism data for this area is somewhat extrapolated based on nearby areas. Displayed data is calculated relative to the peak, so a score of 46.8 in December means 46.8% of the tourists vs. July.

 

 

Overall Great Falls Travel Experience by Season

Spring (March through May)

Humidity and temperatures combine to make this season feel moderately cold. Highs range from 69.9°F (21.1°C) and 39.2°F (4°C) with warmer temperatures in the later months. Rain is somewhat common with 2 to 8 days of significant precipitation per month. Spring is the second busiest for tourism, which makes it a good time for those looking for things to do.

Summer (June through August)

The middle-year months have very comfortable weather with high temperatures that are quite warm. These months see moderate precipitation with 3 to 5 days of precipitation per month. June – August is the busiest season for tourism in Great Falls, so lodging and other accommodations may cost more than usual.

Fall (September through November)

Fall daily highs range from 77.4°F (25.2°C) and 40°F (4.4°C), which will feel chilly given the humidity and wind. It rains or snows a normal amount: approximately 3 days per month. Tourism is fairly slow during these months due to the weather, so hotels may be lower priced.

Winter (December through February)

Weather is far too cold this time of year in Great Falls to be enjoyable for warm weather travelers. The average high during this season is between 42°F (5.6°C) and 32.8°F (0.4°C). On average, it rains or snows a smalll amount: 2 to 3 times per month. These times of year are the slowest with tourists.

 

Best Times to Travel› the United States › Great Falls, MT, US