Photo: Jared Winkler · CC BY-SA 4.0Afternoon heat in Custer trails that of 94% of U.S. towns
The depth of winter brings overnight lows near 13°. Temperatures cover 66° across the year, low to high. Winter nights are cold: in January they are colder than in 89% of U.S. towns. Central heating does most of its work from October to May, in months below 50° on average.
A year in Custer at a glance
Each month’s typical high and low, and what it brings.
What stands out about Custer’s climate
Compared with towns across the U.S., with Custer’s place in South Dakota beside it.
What a year in Custer 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 18 and the first by September 28. Frost and day counts come from NOAA’s station at Custer, SD, 0.8 miles from the town’s center, at about the same height.
The 2023 USDA map puts Custer’s center in zone 5a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −16°. 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 58 inches of snow a winter
Snow, measured at Custer, SD, is heaviest from February through April, about 11 inches a month. Precipitation (rain plus melted snow) adds up to 21 inches a year; May is the wettest month and January the driest. Rain or snow falls on about 94 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Custer
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 Custer, SD.
Living with Custer’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
129 frost-free days in zone 5a. The last frost comes by May 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 28.
Months with highs of 62–84° and lows of 40° or more: June, July, August and September. 4.6 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Custer from natural hazards, wildfire is the largest share (40%); heat waves, cold waves, winter storms and ice storms together are 7%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Custer and similar climates
TownRatings has no climate map of the towns around Custer yet.
Climates most like Custer’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 |
|---|---|---|---|---|
| Custer, SD | 13° | 80° | 21" | 58" |
| Columbia Falls, MT | 18° | 82° | 20" | 54" |
| Gleneagle, CO | 14° | 84° | 21" | 55" |
| Jackson, WY | 6° | 80° | 19" | 78" |
| Alpena, MI | 14° | 78° | 31" | 59" |
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 Custer averaged 1.3° warmer than the 1900s. The biggest change is in January (+4.0°).
A smaller 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 Custer compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Custer’s place among South Dakota’s.
Custer weather by month
Highs, lows and precipitation from NOAA’s grid at Custer’s center; snow, wet days and snow on the ground from Custer, SD. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 36° | 13° | 0.4" | 6.6" | 4 | 18 | 17° – 32° |
| February | 37° | 13° | 0.7" | 10.7" | 6 | 13 | 13° – 34° |
| March | 45° | 21° | 1.0" | 10.7" | 6 | 11 | 22° – 43° |
| April | 51° | 28° | 2.2" | 11.0" | 10 | 6 | 33° – 45° |
| May | 61° | 37° | 3.6" | 2.1" | 14 | 1 | 43° – 54° |
| June | 72° | 46° | 3.4" | 0.0" | 13 | 0 | 52° – 66° |
| July | 80° | 53° | 3.4" | 0.0" | 11 | 0 | 59° – 71° |
| August | 78° | 51° | 2.4" | 0.0" | 9 | 0 | 60° – 68° |
| September | 70° | 42° | 1.6" | 0.8" | 7 | 0 | 50° – 61° |
| October | 55° | 30° | 1.5" | 3.9" | 6 | 2 | 34° – 49° |
| November | 44° | 21° | 0.6" | 6.7" | 4 | 4 | 23° – 42° |
| December | 36° | 14° | 0.5" | 5.4" | 4 | 10 | 16° – 30° |
| Year | 55° | 31° | 21.2" | 57.9" | 94 | 64 |
How much a month can swing
A normal is an average. March swings the most: from 1991 to 2020 its average ranged from 22° to 43°. August is the most reliable, staying within 9°.
Where Custer’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 Custer’s center.
- Snow: Custer, SD (NOAA station in town).
- Frost, freezing nights, 90° and 100° days, heating and cooling: Custer, SD, 0.8 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 Custer’s climate
What is the weather like in Custer?
A typical July afternoon reaches 80°, a January night drops to 13°, and about 58 inches of snow falls in a normal winter. Colder January nights than 89% of U.S. towns; cooler July afternoons than 94% of U.S. towns.
How cold does it get in Custer in winter?
January nights average 13°. About 181 nights a year reach 32° or below and 13 reach 0° or below. In the coldest January of the last 30 years the month averaged 17°.
How much snow does Custer get?
About 58 inches in a normal winter at Custer, SD, heaviest from February through April, about 11 inches a month, with snow on the ground about 64 days a year.
How hot does it get in Custer?
July, with a typical high of 80° and a low of 53°. About 4 days a year reach 90° (Custer, SD).
When is the first and last frost in Custer?
In half of years the last spring frost (32°) comes by May 18 and the first fall frost by September 28, about 129 frost-free days, at Custer, SD.
What growing zone is Custer in?
Zone 5a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −16°.
What is the best time of year to visit Custer?
By one simple rule (highs of 62–84° and lows of 40° or more), June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Custer getting warmer?
Yes: 1991–2020 averaged 1.3° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 51% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Custer.
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.