Three Rivers, SD climate
Three Rivers has cold, snowy winters and warm summers, with very little rain. A typical July afternoon reaches 85°, a January night drops to 4°, and about 43 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Three Rivers feels like
Winter
Spring
Summer
Fall
Three Rivers 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 | 30-yr range |
|---|---|---|---|---|---|---|
| January | 23° | 4° | 0.5" | 8.5" | 6 | 1° – 29° |
| February | 28° | 8° | 0.6" | 7.8" | 6 | 2° – 31° |
| March | 41° | 20° | 0.9" | 5.6" | 6 | 20° – 45° |
| April | 57° | 32° | 2.0" | 5.4" | 8 | 35° – 52° |
| May | 69° | 45° | 3.3" | 0 | 11 | 52° – 64° |
| June | 79° | 55° | 3.7" | 0 | 11 | 62° – 72° |
| July | 85° | 60° | 3.3" | 0 | 9 | 64° – 78° |
| August | 83° | 58° | 2.3" | 0 | 8 | 65° – 75° |
| September | 75° | 48° | 2.2" | 0 | 7 | 54° – 66° |
| October | 59° | 35° | 2.0" | 0.9" | 7 | 40° – 51° |
| November | 42° | 21° | 0.6" | 5.9" | 5 | 20° – 42° |
| December | 28° | 10° | 0.6" | 9.3" | 6 | 5° – 27° |
| Year | 56° | 33° | 21.8" | 43.4" | 88 |
“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 Three Rivers
Three Rivers gets 22 inches of rain and melted snow a year. June is the wettest month and January the driest. Rain or snow falls on about 88 days a year.
About 145 frost-free days a year
In half of years the last 32° night comes by May 8 and the first one by October 1. That leaves about 145 frost-free days for gardens, shorter than 85% of U.S. towns.
Heating and cooling a home in Three Rivers
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Three Rivers, 93% of that work is heating and 7% 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.
Three Rivers and its neighbors
Three Rivers borders 5 towns with climate data. January nights across them vary by 0.8°. Jefferson has the coldest January nights (4°) and Redfield the hottest July afternoons (85°). Three Rivers’s January low is 4° and its July high 85°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Three Rivers 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 Three Rivers averaged 0.7° warmer than the 1900s. The biggest change is in January (+2.7°). The shift is smaller than in 92% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Three Rivers’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 2° to 31°. June is the most reliable, staying within 10°.
Common questions about Three Rivers’s climate
What is the coldest month in Three Rivers?
January, with a typical high of 23° and a low of 4°.
What is the hottest month in Three Rivers?
July, with a typical high of 85° and a low of 60°. About 17 days a year reach 90°.
How much snow does Three Rivers get?
About 43 inches in a normal winter, most of it in December.
When is the first frost in Three Rivers?
In half of years the first 32° night comes by October 1, and the last spring frost by May 8.
What is the rainiest month in Three Rivers?
June, with 3.7 inches of rain and melted snow. The year totals 22 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Three Rivers itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Mellette 4 W, SD (15 mi, snow) and Redfield, SD (5 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.