Red Iron Lake, SD climate
Red Iron Lake has cold, snowy winters and pleasant summers. A typical July afternoon reaches 80°, a January night drops to 3°, and about 48 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Red Iron Lake feels like
Winter
Spring
Summer
Fall
Red Iron Lake 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 | 19° | 3° | 0.7" | 6.6" | 5 | -3° – 24° |
| February | 23° | 6° | 0.7" | 9.2" | 5 | 0° – 26° |
| March | 36° | 19° | 1.2" | 7.0" | 5 | 17° – 41° |
| April | 52° | 31° | 2.2" | 7.2" | 7 | 31° – 50° |
| May | 65° | 44° | 3.2" | 0.2" | 11 | 50° – 61° |
| June | 75° | 55° | 4.1" | 0 | 11 | 59° – 69° |
| July | 80° | 59° | 3.9" | 0 | 9 | 61° – 75° |
| August | 78° | 57° | 2.5" | 0 | 8 | 62° – 71° |
| September | 70° | 48° | 2.6" | 0 | 8 | 53° – 64° |
| October | 54° | 35° | 2.4" | 2.5" | 7 | 37° – 50° |
| November | 38° | 21° | 0.9" | 4.3" | 4 | 17° – 40° |
| December | 24° | 9° | 0.8" | 11.1" | 6 | 2° – 25° |
| Year | 51° | 32° | 25.0" | 48.1" | 84 |
“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 Red Iron Lake
Red Iron Lake gets 25 inches of rain and melted snow a year. June is the wettest month and January the driest. Rain or snow falls on about 84 days a year.
About 160 frost-free days a year
In half of years the last 32° night comes by May 2 and the first one by October 9. That leaves about 160 frost-free days for gardens, shorter than 71% of U.S. towns.
Heating and cooling a home in Red Iron Lake
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Red Iron Lake, 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.
Red Iron Lake and its neighbors
Red Iron Lake borders 4 towns with climate data. January nights across them vary by 1.0°. Buffalo has the coldest January nights (3°) and Long Hollow the hottest July afternoons (81°). Red Iron Lake’s January low is 3° and its July high 80°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Red Iron Lake 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 Red Iron Lake averaged 1.0° warmer than the 1900s. The biggest change is in January (+2.9°). The shift is smaller than in 66% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Red Iron Lake’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. January swings the most: between 1991 and 2020 its average temperature ranged from -3° to 24°. August is the most reliable, staying within 9°.
Common questions about Red Iron Lake’s climate
What is the coldest month in Red Iron Lake?
January, with a typical high of 19° and a low of 3°.
What is the hottest month in Red Iron Lake?
July, with a typical high of 80° and a low of 59°. About 4 days a year reach 90°.
How much snow does Red Iron Lake get?
About 48 inches in a normal winter, most of it in December.
When is the first frost in Red Iron Lake?
In half of years the first 32° night comes by October 9, and the last spring frost by May 2.
What is the rainiest month in Red Iron Lake?
June, with 4.1 inches of rain and melted snow. The year totals 25 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Red Iron Lake itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Roy Lake, SD (7 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.