Sioux Falls, SD Climate & Monthly Averages
The climate of Sioux Falls
The Sioux Falls year is defined by how long its winter lasts: 5 months average sub-freezing nights, bottoming out in January at 11°F (-11°C). Summer is the short exception, with July reaching 83°F (28°C).
Climate quick facts
- Hottest month: July - highs near 83°F (28°C)
- Coldest month: January - highs near 27°F (-3°C)
- Decade extremes (2015-2024): 102°F (39°C) high · -24°F (-31°C) low
- Wettest month: May (12 rainy days) · Sunniest: July (13.2 h sun/day)
- Climate type: humid continental
- Annual swing: 31°C between the average warmest and coolest month · day to night: 10°C
- Snow: about 19 days a year
- Months with freezing average lows: 5
- Average humidity: 68%
Temperatures through the year
January is the coolest month, with highs of 27°F (-3°C) and lows near 11°F (-11°C). Warmth peaks in July: highs of 83°F (28°C), lows of 65°F (18°C). The gridded 2015-2024 daily record for this location tops out at 102°F (39°C) and bottoms at -24°F (-31°C) - decade extremes, not all-time station records. July is the brightest month at 13.2 hours of sun a day, against an annual average of 9.2.
Rain, sun and snow
Overnight lows average at or below freezing for 5 months, November through March. Precipitation concentrates in May - 4.3 inches (110 mm) on 12 days - and thins out by February. Between the average July and the average January lie 31°C, a wider spread than 97% of the 3496 cities in our dataset.
How Sioux Falls compares
- Sioux Falls averages 48°F (9°C) across the year - cooler than all but 6% of the 3496 cities we track.
Ranked against every city in our dataset, each measured on the same ten-year window.
Monthly climate table
| Month | High | Low | Rain days | Precipitation | Sunshine | Daylight | Wet-day chance | Humidity |
|---|---|---|---|---|---|---|---|---|
| January | 27° | 11° | 5 | 1.0 in | 6.1 h/day | 9.3 h | 17% | 75% |
| February | 31° | 13° | 5 | 0.9 in | 7.9 h/day | 10.4 h | 18% | 66% |
| March | 45° | 26° | 6 | 2.2 in | 8.3 h/day | 11.8 h | 21% | 66% |
| April | 56° | 36° | 10 | 3.6 in | 9.2 h/day | 13.4 h | 32% | 62% |
| May | 69° | 49° | 12 | 4.3 in | 10.3 h/day | 14.7 h | 39% | 65% |
| June | 81° | 62° | 10 | 4.0 in | 12.8 h/day | 15.4 h | 32% | 64% |
| July | 83° | 65° | 7 | 2.6 in | 13.2 h/day | 15.1 h | 24% | 70% |
| August | 81° | 63° | 9 | 3.2 in | 11.4 h/day | 14.0 h | 30% | 72% |
| September | 76° | 58° | 8 | 2.7 in | 10.1 h/day | 12.4 h | 27% | 67% |
| October | 59° | 42° | 7 | 2.5 in | 8.0 h/day | 10.9 h | 23% | 64% |
| November | 45° | 29° | 5 | 1.5 in | 6.9 h/day | 9.6 h | 16% | 68% |
| December | 33° | 18° | 6 | 1.5 in | 5.9 h/day | 9.0 h | 18% | 73% |
Sioux Falls month by month
Average high and low for each month, with the bar showing where it sits in Sioux Falls's year (left is the coldest night, right is the warmest afternoon).
January
- Rain
- 5 days
- Sunshine
- 6.1 h
- Daylight
- 9.3 h
- Snow
- 4 days
February
- Rain
- 5 days
- Sunshine
- 7.9 h
- Daylight
- 10.4 h
- Snow
- 4 days
March
- Rain
- 6 days
- Sunshine
- 8.3 h
- Daylight
- 11.8 h
- Snow
- 3 days
April
- Rain
- 10 days
- Sunshine
- 9.2 h
- Daylight
- 13.4 h
- Snow
- 2 days
May
- Rain
- 12 days
- Sunshine
- 10.3 h
- Daylight
- 14.7 h
June
- Rain
- 10 days
- Sunshine
- 12.8 h
- Daylight
- 15.4 h
July
- Rain
- 7 days
- Sunshine
- 13.2 h
- Daylight
- 15.1 h
August
- Rain
- 9 days
- Sunshine
- 11.4 h
- Daylight
- 14.0 h
September
- Rain
- 8 days
- Sunshine
- 10.1 h
- Daylight
- 12.4 h
October
- Rain
- 7 days
- Sunshine
- 8.0 h
- Daylight
- 10.9 h
November
- Rain
- 5 days
- Sunshine
- 6.9 h
- Daylight
- 9.6 h
- Snow
- 2 days
December
- Rain
- 6 days
- Sunshine
- 5.9 h
- Daylight
- 9.0 h
- Snow
- 4 days
Warmer places to go, by month: January · February · March · April · May · June · July · August · September · October · November · December
Seasons in Sioux Falls
Spring (March through May)
Spring in Sioux Falls stays on the cool side of mild, with daytime highs averaging 57°F (14°C) and nights around 37°F (3°C); expect showers on roughly 28 days across the season, plus about 5 snowy days.
Summer (June through August)
Through summer, Sioux Falls sits firmly in the heat: 82°F (28°C) by day, 63°F (17°C) after dark, and expect showers on roughly 26 days across the season. Daylight is generous - around 12.5 hours of sun a day.
Fall (September through November)
Fall stays on the cool side of mild here - highs near 60°F (16°C), nights near 43°F (6°C), and expect showers on roughly 20 days across the season, plus about 2 snowy days.
Winter (December through February)
Through winter, Sioux Falls brings deep cold: 30°F (-1°C) by day, 14°F (-10°C) after dark, and rain comes on about 16 days over the three months, plus about 11 snowy days. Wind sharpens cold like this considerably; pair the forecast winds with the wind speed converter to judge exposed conditions.
Climate questions, answered
Is Sioux Falls hot in summer?
Is Sioux Falls humid?
How warm is Sioux Falls on average?
Is Sioux Falls warmer or cooler than most cities?
What should I wear in Sioux Falls?
Is Sioux Falls cold in winter?
Best time to visit Sioux Falls
The best time to visit Sioux Falls is generally June to October, when these are the warmest and brightest weeks of the year. Daytime temperatures in that window sit near 76°F (24°C), with rain on about 8 days a month. For the same question asked the other way round, see where else is warm in June.
Pack for Sioux Falls with light clothing for the warm months, a heavy insulated coat, hat and gloves for winter and a compact umbrella or rain shell. July nights average 65°F (18°C), so evenings rarely match the afternoons.
Sioux Falls temperature records (2015-2024)
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ. Need the precipitation in other units? The mm-to-inches rainfall converter handles it.