Photo: Ross Griff · CC BY 2.0De Smet’s winters are colder and snowier than most of the U.S.
A typical July afternoon reaches 83°, a January night drops to 5°, and about 41 inches of snow falls in a normal winter.
A year in De Smet at a glance
Each month’s typical high and low, and what it brings.
What stands out about De Smet’s climate
Compared with towns across the U.S., with De Smet’s place in South Dakota beside it.
What a year in De Smet 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 5 and the first by October 4. Frost and day counts come from NOAA’s station at De Smet, SD, 0.2 miles from the town’s center, at about the same height.
The 2023 USDA map puts De Smet’s center in zone 4b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −21°. 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 41 inches of snow a winter
Snow, measured at De Smet, SD, falls mostly in February. Precipitation (rain plus melted snow) adds up to 25 inches a year; June is the wettest month and January the driest. Rain or snow falls on about 74 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in De Smet
94% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at De Smet, SD.
Living with De Smet’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
151 frost-free days in zone 4b. The last frost comes by May 5 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 4.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 0.0 miles of trails are waiting.
Parks & trails →Cold waves are 28% of the yearly building losses FEMA expects in De Smet from natural hazards, the largest share. Normals are averages; the hazards page covers the extremes.
Natural hazards →De Smet and similar climates
TownRatings has no climate map of the towns around De Smet yet.
Climates most like De Smet’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 |
|---|---|---|---|---|
| De Smet, SD | 5° | 83° | 25" | 41" |
| Litchfield, MN | 4° | 82° | 28" | 41" |
| Estherville, IA | 7° | 82° | 31" | 38" |
| West Fargo, ND | 0° | 82° | 24" | 51" |
| Hudson, WI | 6° | 82° | 33" | 50" |
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 De Smet averaged 1.2° warmer than the 1900s. The biggest change is in January (+3.3°).
A smaller 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 De Smet compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with De Smet’s place among South Dakota’s.
De Smet weather by month
Highs, lows and precipitation from NOAA’s grid at De Smet’s center; snow, wet days and snow on the ground from De Smet, SD. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 24° | 5° | 0.6" | 6.2" | 4 | 27 | 2° – 28° |
| February | 29° | 9° | 0.7" | 9.2" | 4 | 21 | 5° – 31° |
| March | 41° | 21° | 1.2" | 6.9" | 5 | 13 | 21° – 47° |
| April | 56° | 33° | 2.4" | 4.8" | 7 | 3 | 35° – 51° |
| May | 68° | 45° | 3.3" | 0.0" | 10 | 0 | 52° – 64° |
| June | 78° | 56° | 4.0" | 0.0" | 10 | 0 | 61° – 71° |
| July | 83° | 61° | 3.3" | 0.0" | 8 | 0 | 63° – 79° |
| August | 80° | 58° | 3.2" | 0.0" | 7 | 0 | 64° – 73° |
| September | 73° | 49° | 2.6" | 0.0" | 6 | 0 | 54° – 67° |
| October | 58° | 36° | 2.1" | 1.6" | 6 | 1 | 38° – 52° |
| November | 42° | 22° | 0.9" | 5.4" | 4 | 6 | 21° – 42° |
| December | 28° | 10° | 0.7" | 7.3" | 4 | 20 | 5° – 26° |
| Year | 55° | 34° | 25.1" | 41.4" | 74 | 91 |
How much a month can swing
A normal is an average. March swings the most: from 1991 to 2020 its average ranged from 21° to 47°. August is the most reliable, staying within 9°.
Where De Smet’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 De Smet’s center.
- Snow: De Smet, SD (NOAA station in town).
- Frost, freezing nights, 90° and 100° days, heating and cooling: De Smet, SD, 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 De Smet’s climate
What is the weather like in De Smet?
A typical July afternoon reaches 83°, a January night drops to 5°, and about 41 inches of snow falls in a normal winter. Colder January nights than 98% of U.S. towns; cooler July afternoons than 72% of U.S. towns.
How cold does it get in De Smet in winter?
January nights average 5°. About 165 nights a year reach 32° or below and 27 reach 0° or below. In the coldest January of the last 30 years the month averaged 2°.
How much snow does De Smet get?
About 41 inches in a normal winter at De Smet, SD, most of it in February, with snow on the ground about 91 days a year.
How hot does it get in De Smet?
July, with a typical high of 83° and a low of 61°. About 10 days a year reach 90° (De Smet, SD).
When is the first and last frost in De Smet?
In half of years the last spring frost (32°) comes by May 5 and the first fall frost by October 4, about 151 frost-free days, at De Smet, SD.
What growing zone is De Smet in?
Zone 4b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −21°.
What is the best time of year to visit De Smet?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is De Smet getting warmer?
Yes: 1991–2020 averaged 1.2° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 63% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in De Smet.
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.