Annual mean 10°C · wettest around May · prevailing wind W
Warmest
27.8 °C
Coldest
-5.4 °C
Wettest
47%
Windiest
7.0 m/s
Prevailing
W
5.5 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Every reading
bars actual · line feels-like, °Cchance of rain, %wind speed, m/ssky covered, %
The average temperature in Sioux City over the whole year is 10°C. July is the hottest month, with highs of about 28°C; January is the coldest, with lows of about -8°C. Sioux City has no sharply defined rainy season: the chance of rain on a given day runs from 32% in February, the driest month, to 48% in May, the wettest. Winds in Sioux City are highest in April, averaging 5.5 m/s (20 km/h), and lightest in July, at 3.2 m/s (12 km/h). The prevailing wind is from the W. The clearest skies in Sioux City come in July, when the sky is typically 22% covered; January is the cloudiest month, at 48%.
Month by month Sioux City climate by month: average temperatures year round · click a month to read it
Month
High
Low
Feels like
Chance of rain
Cloud
Wind
Being outside
Sun
Walking
January
-4°C
-8°C
-11°C
36%
48%
4.5 m/s
0
0
1
February
-2°C
-8°C
-9°C
32%
41%
4.5 m/s
0
0
7
March
7°C
-1°C
0°C
43%
45%
5.1 m/s
4
0
21
April
13°C
4°C
7°C
43%
43%
5.5 m/s
17
1
45
May
20°C
12°C
16°C
48%
41%
4.3 m/s
52
13
61
June
27°C
19°C
26°C
45%
24%
4.1 m/s
52
55
25
July
28°C
20°C
28°C
44%
22%
3.2 m/s
40
66
13
August
26°C
18°C
26°C
43%
28%
3.2 m/s
55
54
25
September
24°C
14°C
22°C
38%
27%
3.7 m/s
67
34
49
October
15°C
6°C
10°C
39%
34%
4.1 m/s
29
2
58
November
7°C
-1°C
1°C
38%
36%
4.4 m/s
5
0
24
December
-0°C
-5°C
-7°C
38%
40%
4.5 m/s
0
0
4
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short Sioux City weather by season
Year round, Sioux City has days of about -4°C at their warmest in January, its coolest month, and 28°C in July, its warmest; the coolest hours of the day run from -8°C to 20°C through the year, and the average temperature over the year is 10°C around the clock. Rain is most likely around May and least likely around February. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
Sioux City weather in winterDecember to February
High -2°CLow -7°CRain 35%
Winter in Sioux City has typical daily highs of about -2°C and lows of about -7°C, with a 35% chance of rain on a given day.
Sioux City weather in springMarch to May
High 13°CLow 5°CRain 45%
Spring in Sioux City has typical daily highs of about 13°C and lows of about 5°C, with a 45% chance of rain on a given day.
Sioux City weather in summerJune to August
High 27°CLow 19°CRain 44%
Summer in Sioux City has typical daily highs of about 27°C and lows of about 19°C, with a 44% chance of rain on a given day.
Sioux City weather in autumnSeptember to November
High 15°CLow 6°CRain 38%
Autumn in Sioux City has typical daily highs of about 15°C and lows of about 6°C, with a 38% chance of rain on a given day.
When is the rainy season in Sioux City?
Sioux City has no sharply defined rainy season: the chance of rain on a given day runs from 32% in February, the driest month, to 48% in May, the wettest.
What time of year is Sioux City windiest?
Winds in Sioux City are highest in April, averaging 5.5 m/s (20 km/h), and lightest in July, at 3.2 m/s (12 km/h). The prevailing wind is from the W.
What is the average temperature in Sioux City year round?
The average temperature in Sioux City over the whole year is 10°C. July is the hottest month, with highs of about 28°C; January is the coldest, with lows of about -8°C.