Dry weather: only 14 inches of rain and melted snow a year in Jefferson City, less than in 94% of U.S. towns
Expect July afternoons of about 82°. Only 70° separates winter nights from summer afternoons. Its January nights bite harder than in 90% of U.S. towns. Garden planting can start around June 18; autumn frost returns near September 5.
A year in Jefferson City at a glance
Each month’s typical high and low, and what it brings.
What stands out about Jefferson City’s climate
Compared with towns across the U.S., with Jefferson City’s place in Montana beside it.
What a year in Jefferson City feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 81 frost-free days a year
In half of years the last 32° night comes by June 18 and the first by September 5. Frost and day counts come from NOAA’s station at Tizer Gardens, MT, 0.5 miles from the town’s center, 410 ft lower.
The 2023 USDA map puts Jefferson City’s center in zone 4b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −22°. 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 37 inches of snow a winter
Snow, measured at Helena Rgnl Airport, falls mostly in December. Precipitation (rain plus melted snow) adds up to 14 inches a year; June is the wettest month and January the driest. Rain or snow falls on about 91 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Jefferson City
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 Tizer Gardens, MT.
Living with Jefferson City’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
81 frost-free days in zone 4b. The last frost comes by Jun 18 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 5.
Months with highs of 62–84° and lows of 40° or more: June, July and August. 24 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Jefferson City from natural hazards, river flooding is the largest share (47%); heat waves, cold waves, winter storms and ice storms together are 20%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Jefferson City and similar climates
TownRatings has no climate map of the towns around Jefferson City yet.
Climates most like Jefferson City’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 |
|---|---|---|---|---|
| Jefferson City, MT | 13° | 82° | 14" | 37" |
| Taos, NM | 11° | 84° | 13" | 28" |
| Cody, WY | 14° | 85° | 11" | 45" |
| Dickinson, ND | 5° | 83° | 16" | 35" |
| Gleneagle, CO | 14° | 84° | 21" | 55" |
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 Jefferson City averaged 1.4° warmer than the 1900s. The biggest change is in January (+4.4°).
A bigger shift than in 51% 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 Jefferson City compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Jefferson City’s place among Montana’s.
Jefferson City weather by month
Highs, lows and precipitation from NOAA’s grid at Jefferson City’s center; snow, wet days and snow on the ground from Helena Rgnl Airport. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 34° | 13° | 0.5" | 6.6" | 7 | 18 | 14° – 29° |
| February | 36° | 14° | 0.5" | 6.6" | 7 | 11 | 11° – 34° |
| March | 46° | 21° | 0.8" | 4.6" | 7 | 5 | 24° – 41° |
| April | 54° | 28° | 1.5" | 2.9" | 9 | 1 | 35° – 46° |
| May | 63° | 36° | 2.2" | 0.1" | 11 | 0 | 44° – 54° |
| June | 71° | 43° | 2.6" | 0.0" | 12 | 0 | 51° – 64° |
| July | 82° | 48° | 1.3" | 0.0" | 8 | 0 | 55° – 72° |
| August | 81° | 46° | 1.2" | 0.3" | 6 | 0 | 57° – 67° |
| September | 70° | 38° | 1.2" | 0.2" | 6 | 0 | 50° – 59° |
| October | 56° | 29° | 1.1" | 2.8" | 7 | 2 | 35° – 48° |
| November | 42° | 20° | 0.7" | 5.4" | 7 | 6 | 23° – 39° |
| December | 33° | 12° | 0.6" | 7.7" | 7 | 14 | 14° – 29° |
| Year | 56° | 29° | 14.3" | 37.2" | 91 | 57 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 11° to 34°. September is the most reliable, staying within 9°.
Where Jefferson City’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 Jefferson City’s center.
- Snow: Helena Rgnl Airport.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Tizer Gardens, MT, 0.5 miles from the town’s center, 410 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 Jefferson City’s climate
What is the weather like in Jefferson City?
A typical July afternoon reaches 82°, a January night drops to 13°, and about 37 inches of snow falls in a normal winter. Colder January nights than 90% of U.S. towns; cooler July afternoons than 81% of U.S. towns.
How cold does it get in Jefferson City in winter?
December nights average 12°. About 223 nights a year reach 32° or below and 27 reach 0° or below. In the coldest December of the last 30 years the month averaged 14°.
How much snow does Jefferson City get?
About 37 inches in a normal winter at Helena Rgnl Airport, most of it in December, with snow on the ground about 57 days a year.
How hot does it get in Jefferson City?
July, with a typical high of 82° and a low of 48°. About 11 days a year reach 90° (Tizer Gardens, MT).
When is the first and last frost in Jefferson City?
In half of years the last spring frost (32°) comes by June 18 and the first fall frost by September 5, about 81 frost-free days, at Tizer Gardens, MT.
What growing zone is Jefferson City in?
Zone 4b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −22°.
What is the best time of year to visit Jefferson City?
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 Jefferson City getting warmer?
Yes: 1991–2020 averaged 1.4° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 51% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Jefferson City.
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.