Sioux Falls, SD Climate & Monthly Averages

South Dakota, United States 🇺🇸 · humid continental climate
Annual avg
48°
Hottest month
July
Coldest month
January
Rainy days / yr
91
Sunshine
9.2 h/day
Right now: 89° and sunny - see live conditions

The climate of Sioux Falls

Located in South Dakota, United States, Sioux Falls experiences a humid continental climate with warm summers and cold, often snowy winters. Afternoon temperatures peak near 83°F (28°C) in July and dip to about 27°F (-3°C) in January, with around 30.0 inches (761 mm) of precipitation falling across the year.

Climate quick facts

  • Hottest month: July - highs near 83°F (28°C)
  • Coldest month: January - highs near 27°F (-3°C)
  • Record high: 102°F (39°C) · Record low: -24°F (-31°C) (2015–2024)
  • Wettest month: May (12 rainy days) · Sunniest: July (13.2 h sun/day)
  • Climate type: humid continental - warm summers and cold, often snowy winters
  • Snow: about 19 days a year

Temperatures through the year

The warmest stretch of the year centers on July. Highs average 83°F (28°C) and overnight lows stay near 65°F (18°C). The coolest month is January, with typical highs of 27°F (-3°C) and lows around 11°F (-11°C). Based on 2015–2024 weather data, temperatures have reached as high as 102°F (39°C) and dropped as low as -24°F (-31°C).

Rain, sun and snow

May is usually the wettest month. It brings about 4.3 inches (110 mm) of rain over 12 days, while February is the driest. July brings the most sunshine, averaging 13.2 hours of sun a day. Snow falls on about 19 days in a typical year, mostly from October through April.

Monthly climate table

Monthly averages for Sioux Falls based on 2015–2024 weather data.
MonthHighLow Rain daysPrecipitation SunshineHumidity
January 27° 11° 5 1.0 in 6.1 h/day 75%
February 31° 13° 5 0.9 in 7.9 h/day 66%
March 45° 26° 6 2.2 in 8.3 h/day 66%
April 56° 36° 10 3.6 in 9.2 h/day 62%
May 69° 49° 12 4.3 in 10.3 h/day 65%
June 81° 62° 10 4.0 in 12.8 h/day 64%
July 83° 65° 7 2.6 in 13.2 h/day 70%
August 81° 63° 9 3.2 in 11.4 h/day 72%
September 76° 58° 8 2.7 in 10.1 h/day 67%
October 59° 42° 7 2.5 in 8.0 h/day 64%
November 45° 29° 5 1.5 in 6.9 h/day 68%
December 33° 18° 6 1.5 in 5.9 h/day 73%

Sioux Falls month by month

Sioux Falls weather in January

January brings highs around 27°F (-3°C), lows near 11°F (-11°C), about 5 wet days and roughly 4 snowy days - typically the coldest month of the year in Sioux Falls.

Sioux Falls weather in February

February brings highs around 31°F (0°C), lows near 13°F (-11°C), about 5 wet days and roughly 4 snowy days - typically the driest month of the year in Sioux Falls.

Sioux Falls weather in March

March brings highs around 45°F (7°C), lows near 26°F (-4°C), about 6 wet days and roughly 3 snowy days.

Sioux Falls weather in April

April brings highs around 56°F (13°C), lows near 36°F (2°C), about 10 wet days and roughly 2 snowy days.

Sioux Falls weather in May

May brings highs around 69°F (20°C), lows near 49°F (10°C), about 12 wet days - typically the wettest month of the year in Sioux Falls.

Sioux Falls weather in June

June brings highs around 81°F (27°C), lows near 62°F (17°C), about 10 wet days.

Sioux Falls weather in July

July brings highs around 83°F (28°C), lows near 65°F (18°C), about 7 wet days - typically the hottest month and the sunniest month of the year in Sioux Falls.

Sioux Falls weather in August

August brings highs around 81°F (27°C), lows near 63°F (17°C), about 9 wet days.

Sioux Falls weather in September

September brings highs around 76°F (24°C), lows near 58°F (14°C), about 8 wet days.

Sioux Falls weather in October

October brings highs around 59°F (15°C), lows near 42°F (6°C), about 7 wet days.

Sioux Falls weather in November

November brings highs around 45°F (7°C), lows near 29°F (-2°C), about 5 wet days and roughly 2 snowy days.

Sioux Falls weather in December

December brings highs around 33°F (0°C), lows near 18°F (-8°C), about 6 wet days and roughly 4 snowy days.

Seasons in Sioux Falls

Spring (March through May)

Spring in Sioux Falls is crisp but comfortable, 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 around 5 snowy days.

Summer (June through August)

Summer in Sioux Falls brings hot afternoons, with daytime highs averaging 82°F (28°C) and nights around 63°F (17°C); expect showers on roughly 26 days across the season.

Fall (September through November)

Fall in Sioux Falls is crisp but comfortable, with daytime highs averaging 60°F (16°C) and nights around 43°F (6°C); expect showers on roughly 20 days across the season, plus around 2 snowy days.

Winter (December through February)

Winter in Sioux Falls is frigid, with daytime highs averaging 30°F (-1°C) and nights around 14°F (-10°C); rain falls on about 16 days over the three months, plus around 11 snowy days. Wind makes those temperatures feel harsher than they sound - pair the forecast winds with the wind speed converter to judge conditions on exposed skin.

Climate questions, answered

What is the average temperature in Sioux Falls?
Sioux Falls averages 48°F (9°C) across the year, with typical daytime highs of 57°F (14°C) and nighttime lows around 39°F (4°C).
Is Sioux Falls hot in summer?
It gets properly warm: plan on 83°F (28°C) through July, with the occasional hotter spike.
Is Sioux Falls cold in winter?
Winter here means deep cold - 11°F (-11°C) is just an average January night, and it has dropped to -24°F (-31°C).
How many rainy days does Sioux Falls get in a year?
About 91 days bring measurable precipitation, with May the wettest month and February the driest.

Best time to visit Sioux Falls

The best time to visit Sioux Falls is generally June to October, when this window offers the warmest, brightest days of the year. Daytime temperatures in that window typically sit near 76°F (24°C).

Pack for Sioux Falls with a heavy insulated coat, hat and gloves for winter; a compact umbrella or rain shell - showers are a regular feature. Evenings can feel noticeably cooler than afternoons - July nights average 65°F (18°C).

Sioux Falls temperature records (2015-2024)

Highest recorded
102°
in August
Lowest recorded
-24°
in January
Annual precipitation
30.0"
Snowy days / yr
19

Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.