Click on a day for an hourly weather forecast
The temperatures in Sioux City in May are comfortable with low of 11°C and and high up to 21°C.
You can expect rain for roughly half of the month of May in Sioux City. We’re expecting roughly 8 to 15 days of rain, so your rubber boots and umbrella are going to see plenty of use this month if you’re keen on staying dry.
Our weather forecast can give you a great sense of what weather to expect in Sioux City in May 2025.
If you’re planning to visit Sioux City in the near future, we highly recommend that you review the 14 day weather forecast for Sioux City before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -2° / -10° | 6 | 22 | 3 | 23 mm | Awful | Sioux City in January |
| February | 0° / -9° | 6 | 19 | 3 | 26 mm | Awful | Sioux City in February |
| March | 9° / -1° | 6 | 23 | 2 | 52 mm | Bad | Sioux City in March |
| April | 15° / 5° | 7 | 22 | 1 | 97 mm | Ok | Sioux City in April |
| May | 21° / 11° | 9 | 22 | 0 | 133 mm | Ok | Sioux City in May |
| June | 27° / 17° | 8 | 22 | 0 | 143 mm | Good | Sioux City in June |
| July | 30° / 19° | 6 | 25 | 0 | 80 mm | Good | Sioux City in July |
| August | 29° / 17° | 7 | 24 | 0 | 123 mm | Ok | Sioux City in August |
| September | 25° / 14° | 5 | 25 | 0 | 77 mm | Perfect | Sioux City in September |
| October | 17° / 7° | 5 | 25 | 0 | 64 mm | Good | Sioux City in October |
| November | 9° / 0° | 4 | 25 | 1 | 33 mm | Ok | Sioux City in November |
| December | 1° / -7° | 6 | 22 | 3 | 41 mm | Awful | Sioux City in December |