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Sioux City, Iowa climate
Dfa Hot-summer humid continental
Sioux City has a strongly seasonal cool-temperate climate (Hot-summer humid continental, Köppen Dfa). The hottest month is July with an average daily high near 31°C, while the coldest is January averaging around −12°C at night. Precipitation totals about 773 mm a year and is strongly seasonal — June alone averages 117 mm while January barely receives 16 mm.
Temperature & precipitation
Daily high–low temperature range with the monthly average, plus monthly precipitation · 1991–2020 normals · hover a month for the exact figuresHours of sunshine per day
Estimated sunny hours each month — daylight length × clear-sky fraction · 1991–2020 monthly cloud cover (NASA POWER)Sioux City climate normals (1991–2020)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 0 | 3 | 11 | 18 | 24 | 29 | 31 | 29 | 27 | 19 | 10 | 3 |
| Avg temp (°C) | −6 | −3 | 4 | 10 | 17 | 22 | 24 | 23 | 19 | 11 | 3 | −4 |
| Avg low (°C) | −12 | −10 | −4 | 2 | 9 | 15 | 17 | 16 | 11 | 3 | −4 | −10 |
| Precipitation (mm) | 16 | 19 | 40 | 79 | 105 | 117 | 97 | 105 | 75 | 59 | 33 | 26 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Avg high (°C) | 0 | 3 | 11 | 18 | 24 | 29 |
| Avg temp (°C) | −6 | −3 | 4 | 10 | 17 | 22 |
| Avg low (°C) | −12 | −10 | −4 | 2 | 9 | 15 |
| Precipitation (mm) | 16 | 19 | 40 | 79 | 105 | 117 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Avg high (°C) | 31 | 29 | 27 | 19 | 10 | 3 |
| Avg temp (°C) | 24 | 23 | 19 | 11 | 3 | −4 |
| Avg low (°C) | 17 | 16 | 11 | 3 | −4 | −10 |
| Precipitation (mm) | 97 | 105 | 75 | 59 | 33 | 26 |
Sky & atmosphere
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cloud cover (%) | 65 | 65 | 66 | 64 | 65 | 57 | 49 | 50 | 47 | 56 | 58 | 63 |
| Relative humidity (%) | 83 | 79 | 72 | 68 | 68 | 70 | 66 | 65 | 64 | 68 | 75 | 83 |
| Wind speed (m/s) | 3.8 | 3.8 | 4.0 | 4.2 | 3.7 | 3.1 | 2.7 | 2.6 | 3.2 | 3.4 | 3.5 | 3.6 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 65 | 65 | 66 | 64 | 65 | 57 |
| Relative humidity (%) | 83 | 79 | 72 | 68 | 68 | 70 |
| Wind speed (m/s) | 3.8 | 3.8 | 4.0 | 4.2 | 3.7 | 3.1 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 49 | 50 | 47 | 56 | 58 | 63 |
| Relative humidity (%) | 66 | 65 | 64 | 68 | 75 | 83 |
| Wind speed (m/s) | 2.7 | 2.6 | 3.2 | 3.4 | 3.5 | 3.6 |
Methodology & sources
Temperature & precipitation — 1991–2020 normals computed from 30 years of daily observations at Sioux Gateway/col Bud Day Field AP, a weather station, about 12 km from the city centre. The underlying daily records come from NOAA's global station network.
Cloud, humidity, wind & sunshine — modelled estimates from NASA POWER, NASA's satellite-and-reanalysis climatology. This is the standard global source for atmospheric variables, which are not measured at most weather stations.