Big Sky Colony has some of the coolest summers among U.S. towns
In January the night’s low is typically 12°. Precipitation is light here, less than falls on 93% of U.S. towns. Since 1901–2000, the year has warmed by 1.8°, most of all in January. The heating season runs October to May: each of those months averages under 50°.
A year in Big Sky Colony at a glance
Each month’s typical high and low, and what it brings.
What stands out about Big Sky Colony’s climate
Compared with towns across the U.S., with Big Sky Colony’s place in Montana beside it.
What a year in Big Sky Colony feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 110 frost-free days a year
In half of years the last 32° night comes by May 28 and the first by September 16. Frost and day counts come from NOAA’s station at Del Bonita, MT, 11 miles from the town’s center, 100 ft higher.
The 2023 USDA map puts Big Sky Colony’s center in zone 4a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −27°. 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 15 inches of rain a year
June is the wettest month and January the driest.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Big Sky Colony
99% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from September 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 Del Bonita, MT.
Living with Big Sky Colony’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
110 frost-free days in zone 4a. The last frost comes by May 28 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 16.
Months with highs of 62–84° and lows of 40° or more: June, July and August.
Parks & trails →Cold waves are 41% of the yearly building losses FEMA expects in Big Sky Colony from natural hazards, the largest share. Normals are averages; the hazards page covers the extremes.
Natural hazards →Big Sky Colony and similar climates
TownRatings has no climate map of the towns around Big Sky Colony yet.
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 Big Sky Colony averaged 1.8° warmer than the 1900s. The biggest change is in January (+5.4°).
A bigger shift than in 77% 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 Big Sky Colony compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Big Sky Colony’s place among Montana’s.
Big Sky Colony weather by month
Highs, lows and precipitation from NOAA’s grid at Big Sky Colony’s center. 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 32° | 12° | 0.6" | 8° – 33° |
| February | 33° | 12° | 0.6" | −2° – 35° |
| March | 40° | 19° | 0.8" | 12° – 38° |
| April | 50° | 27° | 1.2" | 33° – 45° |
| May | 60° | 36° | 2.0" | 42° – 54° |
| June | 67° | 43° | 3.2" | 52° – 60° |
| July | 77° | 48° | 1.3" | 53° – 70° |
| August | 76° | 46° | 1.3" | 55° – 65° |
| September | 66° | 39° | 1.3" | 49° – 58° |
| October | 53° | 30° | 1.0" | 34° – 49° |
| November | 39° | 20° | 0.8" | 17° – 39° |
| December | 32° | 13° | 0.6" | 10° – 32° |
| Year | 52° | 29° | 14.5" |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from -2° to 35°. June is the most reliable, staying within 8°.
Where Big Sky Colony’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 Big Sky Colony’s center.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Del Bonita, MT, 11 miles from the town’s center, 100 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 Big Sky Colony’s climate
What is the weather like in Big Sky Colony?
A typical July afternoon reaches 77°, a January night drops to 12°. Colder January nights than 91% of U.S. towns; cooler July afternoons than 97% of U.S. towns.
How cold does it get in Big Sky Colony in winter?
January nights average 12°. About 198 nights a year reach 32° or below and 26 reach 0° or below. In the coldest January of the last 30 years the month averaged 8°.
How hot does it get in Big Sky Colony?
July, with a typical high of 77° and a low of 48°. About 6 days a year reach 90° (Del Bonita, MT).
When is the first and last frost in Big Sky Colony?
In half of years the last spring frost (32°) comes by May 28 and the first fall frost by September 16, about 110 frost-free days, at Del Bonita, MT.
What growing zone is Big Sky Colony in?
Zone 4a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −27°.
What is the best time of year to visit Big Sky Colony?
By one simple rule (highs of 62–84° and lows of 40° or more), June, July and August. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Big Sky Colony getting warmer?
Yes: 1991–2020 averaged 1.8° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 77% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Big Sky Colony.
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.