Annual mean 14°C · wettest around April · prevailing wind SW
Warmest
30.0 °C
Coldest
0.7 °C
Wettest
25%
Windiest
5.6 m/s
Prevailing
SW
4.3 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 St. Charles over the whole year is 14°C. July is the hottest month, with highs of about 30°C; January is the coldest, with lows of about -2°C. St. Charles has no sharply defined rainy season: the chance of rain on a given day runs from 17% in September, the driest month, to 26% in April, the wettest. Winds in St. Charles are highest in March, averaging 4.1 m/s (15 km/h), and lightest in July, at 2.2 m/s (8 km/h). The prevailing wind is from the SW. The clearest skies in St. Charles come in June, when the sky is typically 28% covered; January is the cloudiest month, at 54%.
Month by month St. Charles 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
2°C
-2°C
-4°C
19%
54%
3.7 m/s
1
0
10
February
5°C
-0°C
0°C
19%
46%
3.7 m/s
7
0
26
March
12°C
5°C
7°C
25%
49%
4.1 m/s
15
0
45
April
17°C
9°C
13°C
26%
43%
4.1 m/s
41
5
63
May
23°C
16°C
21°C
25%
42%
3.3 m/s
63
31
53
June
29°C
21°C
29°C
21%
28%
2.7 m/s
40
58
15
July
30°C
22°C
32°C
22%
30%
2.2 m/s
17
55
4
August
29°C
20°C
30°C
20%
32%
2.2 m/s
33
57
11
September
27°C
16°C
26°C
17%
29%
2.3 m/s
55
54
30
October
19°C
10°C
16°C
20%
39%
3.0 m/s
52
15
63
November
11°C
4°C
7°C
21%
39%
3.2 m/s
19
1
49
December
6°C
1°C
1°C
21%
46%
3.4 m/s
3
0
24
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 St. Charles weather by season
Year round, St. Charles has days of about 2°C at their warmest in January, its coolest month, and 30°C in July, its warmest; the coolest hours of the day run from -2°C to 22°C through the year, and the average temperature over the year is 14°C around the clock. Rain is most likely around April and least likely around September. 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.
St. Charles weather in winterDecember to February
High 4°CLow -1°CRain 20%
Winter in St. Charles has typical daily highs of about 4°C and lows of about -1°C, with a 20% chance of rain on a given day.
St. Charles weather in springMarch to May
High 17°CLow 10°CRain 25%
Spring in St. Charles has typical daily highs of about 17°C and lows of about 10°C, with a 25% chance of rain on a given day.
St. Charles weather in summerJune to August
High 29°CLow 21°CRain 21%
Summer in St. Charles has typical daily highs of about 29°C and lows of about 21°C, with a 21% chance of rain on a given day.
St. Charles weather in autumnSeptember to November
High 19°CLow 10°CRain 19%
Autumn in St. Charles has typical daily highs of about 19°C and lows of about 10°C, with a 19% chance of rain on a given day.
When is the rainy season in St. Charles?
St. Charles has no sharply defined rainy season: the chance of rain on a given day runs from 17% in September, the driest month, to 26% in April, the wettest.
What time of year is St. Charles windiest?
Winds in St. Charles are highest in March, averaging 4.1 m/s (15 km/h), and lightest in July, at 2.2 m/s (8 km/h). The prevailing wind is from the SW.
What is the average temperature in St. Charles year round?
The average temperature in St. Charles over the whole year is 14°C. July is the hottest month, with highs of about 30°C; January is the coldest, with lows of about -2°C.