Great Falls
Montana, USA
Long-term weather forecast
Long-term weather forecast

Monthly weather forecast and climate
Great Falls, MT

A far view from on top of the vast Missouri River of the City of Lights, Great Falls, Montana, a dusk sky, mirror images in the water
A far view from on top of the vast Missouri River of the City of Lights, Great Falls, Montana, a dusk sky, mirror images in the water
January, like December, in Great Falls, Montana, is a wintry winter month, with average temperature fluctuating between -9.5°C (14.9°F) and 1.9°C (35.4°F). In Great Falls, the average high-temperature is essentially the same as in December - a still cold 1.9°C (35.4°F). Weather in January »
The last month of the winter, February, is also a wintry month in Great Falls, Montana, with average temperature varying between -8.7°C (16.3°F) and 3.5°C (38.3°F). In Great Falls, the average high-temperature is practically the same as in January - a still wintry 3.5°C (38.3°F). Weather in February »

The first month of the spring, March, is a frosty month in Great Falls, Montana, with average temperature ranging between max 7.7°C (45.9°F) and min -5.2°C (22.6°F). In March, the average high-temperature marginally rises, from a wintry 3.5°C (38.3°F) in February, to a chilly 7.7°C (45.9°F). Weather in March »

April is a moderate spring month in Great Falls, Montana, with average temperature ranging between max 13.1°C (55.6°F) and min -0.8°C (30.6°F). In April, the average high-temperature increases, from a chilly 7.7°C (45.9°F) in March, to a mild 13.1°C (55.6°F). Weather in April »

May, the last month of the spring, in Great Falls, is a comfortable month, with temperature in the range of an average low of 3.7°C (38.7°F) and an average high of 18.2°C (64.8°F). In May, the average high-temperature rises, from a mild 13.1°C (55.6°F) in April, to a comfortable 18.2°C (64.8°F). Weather in May »

The first month of the summer, June, is a pleasant month in Great Falls, Montana, with temperature in the range of an average high of 22.9°C (73.2°F) and an average low of 7.8°C (46°F). In Great Falls, the average high-temperature slightly increases, from an enjoyable 18.2°C (64.8°F) in May, to an agreeable 22.9°C (73.2°F). Weather in June »

July in Great Falls, Montana, is a moderately hot summer month, with average temperature ranging between min 10.8°C (51.4°F) and max 28.6°C (83.5°F). July is the warmest month, with an average high-temperature of 28.6°C (83.5°F) and an average low-temperature of 10.8°C (51.4°F). Weather in July »

August, the last month of the summer, in Great Falls, is another warm month, with average temperature varying between 10.2°C (50.4°F) and 27.9°C (82.2°F). In Great Falls, the average high-temperature in August is practically the same as in July - a still warm 27.9°C (82.2°F). Weather in August »

September, the first month of the autumn, in Great Falls, is also an agreeable month, with temperature in the range of an average low of 5.6°C (42.1°F) and an average high of 21.3°C (70.3°F). In Great Falls, the average high-temperature decreases, from a moderately hot 27.9°C (82.2°F) in August, to a pleasant 21.3°C (70.3°F). Weather in September »

October, like September, is another mild autumn month in Great Falls, Montana, with temperature in the range of an average high of 14.3°C (57.7°F) and an average low of 0.4°C (32.7°F). In Great Falls, the average high-temperature in October decreases, from an agreeable 21.3°C (70.3°F) in September, to a moderate 14.3°C (57.7°F). Weather in October »

November, the last month of the autumn, in Great Falls, is another chilly month, with average temperature varying between 6.3°C (43.3°F) and -4.8°C (23.4°F). In November, the average high-temperature declines considerably, from a moderate 14.3°C (57.7°F) in October, to a frosty 6.3°C (43.3°F). Weather in November »

The first month of the winter, December, is still a cold month in Great Falls, Montana, with average temperature ranging between min -9.5°C (14.9°F) and max 1.4°C (34.5°F). The coldest month is December, with an average high-temperature of 1.4°C (34.5°F) and an average low-temperature of -9.5°C (14.9°F). Weather in December »

How many days does it rain in Great Falls?

Throughout the year, in Great Falls, Montana, there are 99.9 rainfall days, and 14.8" (374.8mm) of precipitation is accumulated.

When does it snow in Great Falls?

Months with snowfall in Great Falls are January through June, August through December.

How much does it snow in Great Falls?

Throughout the year, in Great Falls, Montana, there are 45.3 snowfall days, and 63.5" (1612.8mm) of snow is accumulated.

What are the months with the lowest UV index in Great Falls?

January, November and December, with an average maximum UV index of 1, are months with the lowest UV index.

What is the driest month in Great Falls?

February is the month with the least rainfall in Great Falls. Rain falls for 7 days and accumulates 0.5" (11.9mm) of precipitation.

What is the snowiest month in Great Falls?

The month with the most snowfall in Great Falls, Montana, is March when snow falls for 7.8 days and typically aggregates up to 11.9" (302.3mm) of snow.

What is the rainiest month in Great Falls?

The month with the most rainfall in Great Falls, Montana, is June when the rain falls for 11.7 days and typically aggregates up to 2.5" (64.3mm) of precipitation.

When are the longest days in Great Falls?

June has the longest days of the year, with an average of 15.9h of daylight.

What are the months with the highest UV index in Great Falls?

June and July, with an average maximum UV index of 8, are months with the highest UV index in Great Falls.

What is the warmest month in Great Falls?

The warmest month in Great Falls is July, with an average high-temperature of 83.5°F (28.6°C) and an average low-temperature of 51.4°F (10.8°C).

What month has the most sunshine in Great Falls?

With an average of 12.2h of sunshine, July has the most sunshine of the year in Great Falls, Montana.

What is the coldest month in Great Falls?

December is the coldest month, with an average high-temperature of 34.5°F (1.4°C) and an average low-temperature of 14.9°F (-9.5°C).

What is the month with the shortest days in Great Falls?

December has the shortest days of the year, with an average of 8.5h of daylight.

What is the month with the least sunshine in Great Falls?

December has the least sunshine of the year in Great Falls, with an average of 3.4h of sunshine.
Average temperature - Great Falls, MT
Average rainfall - Great Falls, MT
Average rainfall days - Great Falls, MT

Months with the highest number of rainy days are May and June (11.7 days).
The month with the lowest number of rainy days is October (6.6 days).

Average snowfall days - Great Falls, MT

The month with the highest number of snowfall days is March (7.8 days).
The month with the lowest number of snowfall days is July (0 days).

Average daylight / Average sunshine - Great Falls, MT