Boulder Canyon, SD climate
Boulder Canyon has cold, snowy winters and pleasant summers. A typical July afternoon reaches 84°, a January night drops to 15°, and about 48 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Boulder Canyon feels like
Winter
Spring
Summer
Fall
Boulder Canyon 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 | 37° | 15° | 0.8" | 5.3" | 6 | 11 | 17° – 36° |
| February | 38° | 15° | 1.1" | 8.3" | 7 | 12 | 9° – 36° |
| March | 47° | 23° | 1.5" | 8.4" | 7 | 7 | 23° – 46° |
| April | 55° | 31° | 2.8" | 7.9" | 9 | 3 | 36° – 49° |
| May | 65° | 41° | 4.6" | 1.4" | 12 | 0 | 45° – 58° |
| June | 76° | 50° | 3.5" | 0 | 12 | 0 | 57° – 70° |
| July | 84° | 57° | 2.6" | 0 | 9 | 0 | 62° – 76° |
| August | 82° | 54° | 2.0" | 0 | 7 | 0 | 63° – 73° |
| September | 73° | 45° | 1.6" | 0 | 6 | 0 | 52° – 65° |
| October | 59° | 33° | 2.2" | 2.8" | 8 | 2 | 37° – 52° |
| November | 46° | 23° | 1.1" | 5.3" | 6 | 4 | 25° – 44° |
| December | 38° | 16° | 0.9" | 8.2" | 5 | 12 | 18° – 34° |
| Year | 58° | 34° | 24.8" | 47.6" | 94 | 51 |
“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 Boulder Canyon
Boulder Canyon gets 25 inches of rain and melted snow a year. May is the wettest month and January the driest. Rain or snow falls on about 94 days a year. Snow covers the ground about 51 days of the year.
About 125 frost-free days a year
In half of years the last 32° night comes by May 24 and the first one by September 25. That leaves about 125 frost-free days for gardens, shorter than 96% of U.S. towns.
Heating and cooling a home in Boulder Canyon
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Boulder Canyon, 95% of that work is heating and 5% 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.
How Boulder Canyon 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 Boulder Canyon averaged 1.2° warmer than the 1900s. The biggest change is in March (+3.5°). The shift is larger than in 51% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Boulder Canyon’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 9° to 36°. August is the most reliable, staying within 11°.
Common questions about Boulder Canyon’s climate
What is the coldest month in Boulder Canyon?
January, with a typical high of 37° and a low of 15°.
What is the hottest month in Boulder Canyon?
July, with a typical high of 84° and a low of 57°. About 15 days a year reach 90°.
How much snow does Boulder Canyon get?
About 48 inches in a normal winter, most of it in March.
When is the first frost in Boulder Canyon?
In half of years the first 32° night comes by September 25, and the last spring frost by May 24.
What is the rainiest month in Boulder Canyon?
May, with 4.6 inches of rain and melted snow. The year totals 25 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Boulder Canyon itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Ft Meade, SD (6 mi, snow) and Deadwood, SD (6 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.