Sunnybrook Colony sits near the bottom of U.S. towns for precipitation, with 12 inches a year
July afternoons average 84°. Its January nights bite harder than in 95% of U.S. towns. Warming shows here too: 1.6° more than in 1901–2000, led by January. Keep the boiler serviced for the months from October to April, which average under 50°.
A year in Sunnybrook Colony at a glance
Each month’s typical high and low, and what it brings.
What stands out about Sunnybrook Colony’s climate
Compared with towns across the U.S., with Sunnybrook Colony’s place in Montana beside it.
What a year in Sunnybrook Colony feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 129 frost-free days a year
In half of years the last 32° night comes by May 16 and the first by September 23. Day counts come from NOAA’s station at Rudyard 19s, MT, 10 miles from the town’s center, 190 ft lower; frost dates and degree days from Tiber Dam, MT, 20 miles away.
The 2023 USDA map puts Sunnybrook 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 36 inches of snow a winter
Snow, measured at Loma, MT, falls mostly in January. Precipitation (rain plus melted snow) adds up to 12 inches a year; June is the wettest month and February the driest. Rain or snow falls on about 76 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Sunnybrook Colony
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 Tiber Dam, MT.
Living with Sunnybrook Colony’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
129 frost-free days in zone 4a. The last frost comes by May 16 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 23.
Months with highs of 62–84° and lows of 40° or more: June, August and September.
Parks & trails →Of the yearly building losses FEMA expects in Sunnybrook Colony from natural hazards, river flooding is the largest share (63%); heat waves, cold waves, winter storms and ice storms together are 24%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Sunnybrook Colony and similar climates
TownRatings has no climate map of the towns around Sunnybrook Colony yet.
Climates most like Sunnybrook Colony’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 |
|---|---|---|---|---|
| Sunnybrook Colony, MT | 9° | 84° | 12" | 36" |
| Taos, NM | 11° | 84° | 13" | 28" |
| Salida, CO | 10° | 85° | 8" | 37" |
| Cody, WY | 14° | 85° | 11" | 45" |
| Dickinson, ND | 5° | 83° | 16" | 35" |
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 Sunnybrook Colony averaged 1.6° warmer than the 1900s. The biggest change is in January (+4.8°).
A bigger shift than in 63% 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 Sunnybrook Colony compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Sunnybrook Colony’s place among Montana’s.
Sunnybrook Colony weather by month
Highs, lows and precipitation from NOAA’s grid at Sunnybrook Colony’s center; snow, wet days and snow on the ground from Loma, MT. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 31° | 9° | 0.4" | 8.4" | 5 | 18 | 7° – 35° |
| February | 35° | 12° | 0.4" | 5.4" | 5 | 13 | −4° – 37° |
| March | 46° | 20° | 0.4" | 5.0" | 5 | 9 | 16° – 41° |
| April | 56° | 30° | 1.1" | 1.9" | 8 | 2 | 38° – 47° |
| May | 67° | 39° | 1.9" | 0.8" | 10 | 0 | 48° – 59° |
| June | 75° | 47° | 2.6" | 0.0" | 10 | 0 | 57° – 66° |
| July | 84° | 52° | 1.2" | 0.0" | 6 | 0 | 59° – 76° |
| August | 83° | 51° | 1.1" | 0.0" | 5 | 0 | 62° – 72° |
| September | 72° | 42° | 1.0" | 0.0" | 5 | 0 | 53° – 63° |
| October | 58° | 31° | 0.8" | 1.6" | 6 | 1 | 35° – 50° |
| November | 43° | 20° | 0.5" | 6.1" | 5 | 6 | 19° – 40° |
| December | 33° | 12° | 0.4" | 7.1" | 5 | 13 | 9° – 34° |
| Year | 57° | 30° | 11.8" | 36.3" | 76 | 61 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from -4° to 37°. June is the most reliable, staying within 8°.
Where Sunnybrook 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 Sunnybrook Colony’s center.
- Snow: Loma, MT.
- Frost dates, heating and cooling: Tiber Dam, MT, 20 miles away.
- Freezing nights, 90° and 100° days: Rudyard 19s, MT, 10 miles from the town’s center, 190 ft lower; 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 Sunnybrook Colony’s climate
What is the weather like in Sunnybrook Colony?
A typical July afternoon reaches 84°, a January night drops to 9°, and about 36 inches of snow falls in a normal winter. Colder January nights than 95% of U.S. towns; cooler July afternoons than 57% of U.S. towns.
How cold does it get in Sunnybrook Colony in winter?
January nights average 9°. About 196 nights a year reach 32° or below and 34 reach 0° or below. In the coldest January of the last 30 years the month averaged 7°.
How much snow does Sunnybrook Colony get?
About 36 inches in a normal winter at Loma, MT, most of it in January, with snow on the ground about 61 days a year.
How hot does it get in Sunnybrook Colony?
July, with a typical high of 84° and a low of 52°. About 23 days a year reach 90° and 1 reach 100° (Tiber Dam, MT).
When is the first and last frost in Sunnybrook Colony?
In half of years the last spring frost (32°) comes by May 16 and the first fall frost by September 23, about 129 frost-free days, at Tiber Dam, MT.
What growing zone is Sunnybrook 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 Sunnybrook Colony?
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 Sunnybrook Colony getting warmer?
Yes: 1991–2020 averaged 1.6° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 63% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Sunnybrook 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.