Few U.S. towns get less rain and snow than Sun Prairie: 12 inches a year
In July the day’s top temperature is typically 85°. By January nights alone, it runs colder than 89% of U.S. towns. Decade by decade the climate has edged up, 1.3° above 1901–2000. Radiators earn their keep from October to April, the months that average under 50°.
A year in Sun Prairie at a glance
Each month’s typical high and low, and what it brings.
What stands out about Sun Prairie’s climate
Compared with towns across the U.S., with Sun Prairie’s place in Montana beside it.
What a year in Sun Prairie feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 126 frost-free days a year
In half of years the last 32° night comes by May 19 and the first by September 24. Frost and day counts come from NOAA’s station at Great Falls International Airport, 7 miles from the town’s center, 310 ft higher.
The 2023 USDA map puts Sun Prairie’s center in zone 4b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −25°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 49 inches of snow a winter
Snow, measured at Power 6 Se, MT, falls mostly in April. Precipitation (rain plus melted snow) adds up to 12 inches a year; June is the wettest month and December the driest. Rain or snow falls on about 93 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Sun Prairie
96% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through May.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Great Falls International Airport.
Living with Sun Prairie’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
126 frost-free days in zone 4b. The last frost comes by May 19 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Sep 24.
Months with highs of 62–84° and lows of 40° or more: June, August and September.
Parks & trails →Cold waves are 53% of the yearly building losses FEMA expects in Sun Prairie from natural hazards, the largest share. Normals are averages; the hazards page covers the extremes.
Natural hazards →Sun Prairie and similar climates
TownRatings has no climate map of the towns around Sun Prairie yet.
Climates most like Sun Prairie’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Sun Prairie, MT | 13° | 85° | 12" | 49" |
| Cody, WY | 14° | 85° | 11" | 45" |
| Rigby, ID | 12° | 85° | 12" | 66" |
| Gypsum, CO | 11° | 86° | 14" | 39" |
| Doney Park, AZ | 17° | 86° | 16" | 52" |
Temperatures and precipitation come from NOAA’s 5 km grid; snow and day counts from the stations named on this page.
Warmer than it used to be
The last 30 years in Sun Prairie averaged 1.3° warmer than the 1900s. The biggest change is in January (+5.0°).
A smaller shift than in 53% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Sun Prairie compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Sun Prairie’s place among Montana’s.
Sun Prairie weather by month
Highs, lows and precipitation from NOAA’s grid at Sun Prairie’s center; snow, wet days and snow on the ground from Power 6 Se, MT. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 36° | 13° | 0.4" | 6.1" | 7 | 21 | 12° – 36° |
| February | 38° | 14° | 0.4" | 5.2" | 7 | 17 | −1° – 38° |
| March | 47° | 22° | 0.5" | 7.9" | 8 | 12 | 18° – 44° |
| April | 56° | 30° | 1.4" | 9.4" | 10 | 6 | 37° – 48° |
| May | 66° | 39° | 2.1" | 3.1" | 11 | 2 | 48° – 57° |
| June | 74° | 46° | 2.5" | 1.2" | 11 | 0 | 56° – 66° |
| July | 85° | 51° | 1.1" | 0.0" | 7 | 0 | 58° – 76° |
| August | 84° | 50° | 1.0" | 0.4" | 7 | 0 | 60° – 71° |
| September | 73° | 42° | 1.1" | 0.6" | 7 | 0 | 52° – 63° |
| October | 58° | 32° | 0.8" | 4.0" | 7 | 3 | 36° – 52° |
| November | 44° | 22° | 0.5" | 6.0" | 6 | 10 | 21° – 43° |
| December | 36° | 15° | 0.4" | 5.1" | 7 | 17 | 14° – 35° |
| Year | 58° | 31° | 12.0" | 49.0" | 93 | 88 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from -1° to 38°. May is the most reliable, staying within 10°.
Where Sun Prairie’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Sun Prairie’s center.
- Snow: Power 6 Se, MT.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Great Falls International Airport, 7 miles from the town’s center, 310 ft higher; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Sun Prairie’s climate
What is the weather like in Sun Prairie?
A typical July afternoon reaches 85°, a January night drops to 13°, and about 49 inches of snow falls in a normal winter. Colder January nights than 89% of U.S. towns; cooler July afternoons than 55% of U.S. towns.
How cold does it get in Sun Prairie in winter?
January nights average 13°. About 168 nights a year reach 32° or below and 21 reach 0° or below. In the coldest January of the last 30 years the month averaged 12°.
How much snow does Sun Prairie get?
About 49 inches in a normal winter at Power 6 Se, MT, most of it in April, with snow on the ground about 88 days a year.
How hot does it get in Sun Prairie?
July, with a typical high of 85° and a low of 51°. About 22 days a year reach 90° (Great Falls International Airport).
When is the first and last frost in Sun Prairie?
In half of years the last spring frost (32°) comes by May 19 and the first fall frost by September 24, about 126 frost-free days, at Great Falls International Airport.
What growing zone is Sun Prairie in?
Zone 4b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −25°.
What is the best time of year to visit Sun Prairie?
By one simple rule (highs of 62–84° and lows of 40° or more), June, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Sun Prairie getting warmer?
Yes: 1991–2020 averaged 1.3° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 53% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Sun Prairie.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.