Cedarvale · Photo: National Park Service · Public domainDry weather: only 16 inches of rain and melted snow a year in Fort Smith, less than in 92% of U.S. towns
On a normal July day the thermometer tops out near 88°. The wettest month is May; the driest is December. Its January nights bite harder than in 87% of U.S. towns. The frost-free window for a garden runs roughly May 7 to October 5.
A year in Fort Smith at a glance
Each month’s typical high and low, and what it brings.
What stands out about Fort Smith’s climate
Compared with towns across the U.S., with Fort Smith’s place in Montana beside it.
What a year in Fort Smith feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 151 frost-free days a year
In half of years the last 32° night comes by May 7 and the first by October 5. Frost and day counts come from NOAA’s station at Yellowtail Dam, MT, 0.2 miles from the town’s center, at about the same height.
The 2023 USDA map puts Fort Smith’s center in zone 5b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −13°. 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 44 inches of snow a winter
Snow, measured at Yellowtail Dam, MT, falls mostly in January and March. Precipitation (rain plus melted snow) adds up to 16 inches a year; May is the wettest month and December the driest. Rain or snow falls on about 66 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Fort Smith
90% 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 Yellowtail Dam, MT.
Living with Fort Smith’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
151 frost-free days in zone 5b. The last frost comes by May 7 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Oct 5.
Months with highs of 62–84° and lows of 40° or more: May, June and September.
Parks & trails →Of the yearly building losses FEMA expects in Fort Smith from natural hazards, river flooding is the largest share (47%); heat waves, cold waves, winter storms and ice storms together are 19%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Fort Smith and similar climates
TownRatings has no climate map of the towns around Fort Smith yet.
Climates most like Fort Smith’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 |
|---|---|---|---|---|
| Fort Smith, MT | 14° | 88° | 16" | 44" |
| Alliance, NE | 13° | 88° | 17" | 45" |
| Hyde Park, UT | 14° | 89° | 16" | 44" |
| Spring Creek, NV | 15° | 89° | 14" | 41" |
| Belle Fourche, SD | 13° | 88° | 19" | 42" |
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 Fort Smith averaged 1.5° warmer than the 1900s. The biggest change is in January (+4.2°).
A bigger shift than in 56% 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 Fort Smith compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Fort Smith’s place among Montana’s.
Fort Smith weather by month
Highs, lows and precipitation from NOAA’s grid at Fort Smith’s center; snow, wet days and snow on the ground from Yellowtail Dam, MT. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 35° | 14° | 0.7" | 8.8" | 5 | 15° – 34° |
| February | 39° | 16° | 0.8" | 7.4" | 5 | 9° – 38° |
| March | 50° | 25° | 1.2" | 8.4" | 6 | 27° – 46° |
| April | 58° | 32° | 2.0" | 3.0" | 8 | 39° – 50° |
| May | 68° | 42° | 2.7" | 0.2" | 8 | 50° – 60° |
| June | 78° | 51° | 2.1" | 0.0" | 7 | 57° – 70° |
| July | 88° | 57° | 1.1" | 0.0" | 5 | 62° – 78° |
| August | 86° | 54° | 0.8" | 0.0" | 4 | 65° – 76° |
| September | 75° | 45° | 1.5" | 0.0" | 5 | 55° – 66° |
| October | 60° | 33° | 1.9" | 3.0" | 6 | 39° – 53° |
| November | 46° | 23° | 0.8" | 5.8" | 4 | 23° – 45° |
| December | 36° | 15° | 0.6" | 7.3" | 5 | 15° – 33° |
| Year | 60° | 34° | 16.1" | 43.9" | 66 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 9° to 38°. May is the most reliable, staying within 10°.
Where Fort Smith’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 Fort Smith’s center.
- Snow: Yellowtail Dam, MT (NOAA station in town).
- Frost, freezing nights, 90° and 100° days, heating and cooling: Yellowtail Dam, MT, 0.2 miles from the town’s center, at about the same height; 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 Fort Smith’s climate
What is the weather like in Fort Smith?
A typical July afternoon reaches 88°, a January night drops to 14°, and about 44 inches of snow falls in a normal winter. Colder January nights than 87% of U.S. towns; hotter July afternoons than 68% of U.S. towns.
How cold does it get in Fort Smith in winter?
January nights average 14°. About 126 nights a year reach 32° or below and 11 reach 0° or below. In the coldest January of the last 30 years the month averaged 15°.
How much snow does Fort Smith get?
About 44 inches in a normal winter at Yellowtail Dam, MT, most of it in January and March.
How hot does it get in Fort Smith?
July, with a typical high of 88° and a low of 57°. About 45 days a year reach 90° and 6 reach 100° (Yellowtail Dam, MT).
When is the first and last frost in Fort Smith?
In half of years the last spring frost (32°) comes by May 7 and the first fall frost by October 5, about 151 frost-free days, at Yellowtail Dam, MT.
What growing zone is Fort Smith in?
Zone 5b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −13°.
What is the best time of year to visit Fort Smith?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Fort Smith getting warmer?
Yes: 1991–2020 averaged 1.5° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 56% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Fort Smith.
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.