Grand River, SD climate
Grand River has cold, snowy winters and warm summers, with very little rain. A typical July afternoon reaches 85°, a January night drops to 6°, and about 42 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Grand River feels like
Winter
Spring
Summer
Fall
Grand River weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 28° | 6° | 0.3" | 4.5" | 4 | 22 | 8° – 29° |
| February | 31° | 10° | 0.4" | 7.6" | 4 | 18 | 0° – 32° |
| March | 43° | 19° | 0.7" | 7.5" | 5 | 12 | 19° – 45° |
| April | 56° | 29° | 1.4" | 4.8" | 7 | 3 | 36° – 49° |
| May | 66° | 40° | 2.6" | 0.7" | 9 | 0 | 48° – 59° |
| June | 77° | 50° | 2.9" | 0 | 10 | 0 | 59° – 69° |
| July | 85° | 56° | 2.2" | 0 | 9 | 0 | 62° – 77° |
| August | 84° | 53° | 1.6" | 0 | 7 | 0 | 63° – 74° |
| September | 74° | 44° | 1.3" | 0 | 6 | 0 | 52° – 65° |
| October | 58° | 31° | 1.3" | 3.1" | 6 | 2 | 36° – 49° |
| November | 42° | 19° | 0.5" | 5.2" | 4 | 8 | 18° – 41° |
| December | 31° | 9° | 0.3" | 8.9" | 4 | 16 | 8° – 28° |
| Year | 56° | 31° | 15.3" | 42.3" | 73 | 80 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Grand River
Grand River gets 15 inches of rain and melted snow a year. June is the wettest month and January the driest. Rain or snow falls on about 73 days a year. Snow covers the ground about 80 days of the year.
About 115 frost-free days a year
In half of years the last 32° night comes by May 24 and the first one by September 18. That leaves about 115 frost-free days for gardens, shorter than 98% of U.S. towns.
Heating and cooling a home in Grand River
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Grand River, 96% of that work is heating and 4% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Grand River and its neighbors
Grand River borders 2 towns with climate data. January nights across them vary by 1.0°. Hettinger has the coldest January nights (7°) and Lodgepole the hottest July afternoons (85°). Grand River’s January low is 6° and its July high 85°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Grand River compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Grand River averaged 1.5° warmer than the 1900s. The biggest change is in January (+4.4°). The shift is larger than in 72% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Grand River’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 0° to 32°. June is the most reliable, staying within 10°.
Common questions about Grand River’s climate
What is the coldest month in Grand River?
January, with a typical high of 28° and a low of 6°.
What is the hottest month in Grand River?
July, with a typical high of 85° and a low of 56°. About 24 days a year reach 90°.
How much snow does Grand River get?
About 42 inches in a normal winter, most of it in December.
When is the first frost in Grand River?
In half of years the first 32° night comes by September 18, and the last spring frost by May 24.
What is the rainiest month in Grand River?
June, with 2.9 inches of rain and melted snow. The year totals 15 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Grand River itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Lemmon, SD (23 mi, snow) and Hettinger Municipal Airport, ND (9 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.