Annual mean 10°C · wettest around May · prevailing wind W
Warmest
25.6 °C
Coldest
-2.2 °C
Wettest
21%
Windiest
4.8 m/s
Prevailing
W
4.0 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. Marys over the whole year is 10°C. July is the hottest month, with highs of about 25°C; January is the coldest, with lows of about -4°C. St. Marys has no sharply defined rainy season: the chance of rain on a given day runs from 17% in September, the driest month, to 23% in May, the wettest. Winds in St. Marys are highest in March, averaging 3.8 m/s (14 km/h), and lightest in July, at 2.2 m/s (8 km/h). The prevailing wind is from the W. The clearest skies in St. Marys come in July, when the sky is typically 44% covered; January is the cloudiest month, at 75%.
Month by month St. Marys 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
-4°C
-8°C
18%
75%
3.7 m/s
0
0
3
February
1°C
-3°C
-5°C
21%
65%
3.7 m/s
1
0
8
March
6°C
-0°C
0°C
19%
59%
3.8 m/s
4
0
23
April
11°C
5°C
7°C
23%
58%
3.5 m/s
19
1
48
May
18°C
10°C
15°C
23%
55%
2.9 m/s
52
9
68
June
23°C
15°C
21°C
21%
47%
2.7 m/s
72
27
59
July
25°C
17°C
25°C
18%
44%
2.2 m/s
70
53
31
August
24°C
16°C
24°C
18%
50%
2.2 m/s
76
43
41
September
21°C
13°C
19°C
17%
48%
2.2 m/s
70
21
66
October
15°C
8°C
11°C
18%
55%
2.8 m/s
35
3
64
November
6°C
2°C
2°C
17%
59%
3.3 m/s
5
0
24
December
1°C
-1°C
-4°C
21%
73%
3.5 m/s
0
0
6
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. Marys weather by season
Year round, St. Marys has days of about -2°C at their warmest in January, its coolest month, and 25°C in July, its warmest; the coolest hours of the day run from -4°C to 17°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 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. Marys weather in winterDecember to February
High 0°CLow -3°CRain 20%
Winter in St. Marys has typical daily highs of about 0°C and lows of about -3°C, with a 20% chance of rain on a given day.
St. Marys weather in springMarch to May
High 12°CLow 5°CRain 22%
Spring in St. Marys has typical daily highs of about 12°C and lows of about 5°C, with a 22% chance of rain on a given day.
St. Marys weather in summerJune to August
High 24°CLow 16°CRain 19%
Summer in St. Marys has typical daily highs of about 24°C and lows of about 16°C, with a 19% chance of rain on a given day.
St. Marys weather in autumnSeptember to November
High 14°CLow 8°CRain 17%
Autumn in St. Marys has typical daily highs of about 14°C and lows of about 8°C, with a 17% chance of rain on a given day.
When is the rainy season in St. Marys?
St. Marys has no sharply defined rainy season: the chance of rain on a given day runs from 17% in September, the driest month, to 23% in May, the wettest.
What time of year is St. Marys windiest?
Winds in St. Marys are highest in March, averaging 3.8 m/s (14 km/h), and lightest in July, at 2.2 m/s (8 km/h). The prevailing wind is from the W.
What is the average temperature in St. Marys year round?
The average temperature in St. Marys over the whole year is 10°C. July is the hottest month, with highs of about 25°C; January is the coldest, with lows of about -4°C.