Lewis and Clark Caverns Historic District · Photo: Montanabw · CC BY-SA 3.0Cardwell’s winters are colder than most of the U.S.; July afternoons average 86°
A typical July afternoon reaches 86°, a January night drops to 13°.
A year in Cardwell at a glance
Each month’s typical high and low, and what it brings.
What stands out about Cardwell’s climate
Compared with towns across the U.S., with Cardwell’s place in Montana beside it.
What a year in Cardwell feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 139 frost-free days a year
In half of years the last 32° night comes by May 9 and the first by September 27. Frost and day counts come from NOAA’s station at Trident, MT, 24 miles from the town’s center, 250 ft lower.
The 2023 USDA map puts Cardwell’s center in zone 5a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −18°. 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 13 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 Cardwell
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 Trident, MT.
Living with Cardwell’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
139 frost-free days in zone 5a. The last frost comes by May 9 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 27.
Months with highs of 62–84° and lows of 40° or more: June.
Parks & trails →Of the yearly building losses FEMA expects in Cardwell from natural hazards, river flooding is the largest share (54%); heat waves, cold waves, winter storms and ice storms together are 20%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Cardwell and similar climates
TownRatings has no climate map of the towns around Cardwell 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 Cardwell averaged 1.4° warmer than the 1900s. The biggest change is in January (+4.1°).
A bigger shift than in 54% 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 Cardwell compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Cardwell’s place among Montana’s.
Cardwell weather by month
Highs, lows and precipitation from NOAA’s grid at Cardwell’s center. 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 37° | 13° | 0.3" | 17° – 31° |
| February | 40° | 15° | 0.3" | 16° – 36° |
| March | 50° | 23° | 0.9" | 29° – 42° |
| April | 57° | 29° | 1.6" | 37° – 48° |
| May | 67° | 37° | 2.1" | 48° – 57° |
| June | 76° | 44° | 2.5" | 54° – 67° |
| July | 86° | 49° | 1.1" | 57° – 75° |
| August | 85° | 47° | 1.0" | 59° – 70° |
| September | 74° | 39° | 1.3" | 52° – 61° |
| October | 60° | 30° | 1.0" | 36° – 51° |
| November | 45° | 20° | 0.5" | 25° – 41° |
| December | 35° | 12° | 0.5" | 16° – 29° |
| Year | 59° | 30° | 12.9" |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 16° to 36°. September is the most reliable, staying within 9°.
Where Cardwell’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 Cardwell’s center.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Trident, MT, 24 miles from the town’s center, 250 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 Cardwell’s climate
What is the weather like in Cardwell?
A typical July afternoon reaches 86°, a January night drops to 13°. Colder January nights than 89% of U.S. towns; hotter July afternoons than 58% of U.S. towns.
How cold does it get in Cardwell in winter?
December nights average 12°. About 174 nights a year reach 32° or below and 15 reach 0° or below. In the coldest December of the last 30 years the month averaged 16°.
How hot does it get in Cardwell?
July, with a typical high of 86° and a low of 49°. About 25 days a year reach 90° and 1 reach 100° (Trident, MT).
When is the first and last frost in Cardwell?
In half of years the last spring frost (32°) comes by May 9 and the first fall frost by September 27, about 139 frost-free days, at Trident, MT.
What growing zone is Cardwell in?
Zone 5a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −18°.
What is the best time of year to visit Cardwell?
By one simple rule (highs of 62–84° and lows of 40° or more), June. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Cardwell getting warmer?
Yes: 1991–2020 averaged 1.4° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 54% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Cardwell.
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.