Annual mean 14°C · wettest around May · prevailing wind SW
Warmest
30.0 °C
Coldest
0.7 °C
Wettest
36%
Windiest
6.4 m/s
Prevailing
SW
5.0 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 Ottawa 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 -3°C. Ottawa has no sharply defined rainy season: the chance of rain on a given day runs from 22% in October, the driest month, to 35% in May, the wettest. Winds in Ottawa are highest in April, averaging 5.0 m/s (18 km/h), and lightest in July, at 3.1 m/s (11 km/h). The prevailing wind is from the SW. The clearest skies in Ottawa come in September, when the sky is typically 19% covered; January is the cloudiest month, at 36%.
Month by month Ottawa 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
-3°C
-4°C
27%
36%
4.1 m/s
2
0
11
February
6°C
-1°C
-0°C
26%
30%
4.4 m/s
8
0
27
March
12°C
5°C
7°C
32%
35%
4.9 m/s
17
1
46
April
17°C
9°C
12°C
32%
32%
5.0 m/s
39
3
65
May
22°C
15°C
20°C
35%
35%
3.8 m/s
64
27
56
June
29°C
21°C
29°C
32%
19%
3.6 m/s
36
63
14
July
30°C
22°C
31°C
28%
19%
3.1 m/s
19
62
4
August
29°C
21°C
30°C
30%
22%
3.1 m/s
31
61
10
September
27°C
17°C
26°C
28%
19%
3.3 m/s
55
57
29
October
19°C
11°C
15°C
22%
25%
3.9 m/s
51
15
61
November
12°C
5°C
7°C
28%
26%
4.0 m/s
16
1
47
December
6°C
1°C
1°C
24%
31%
4.1 m/s
4
0
22
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 Ottawa weather by season
Year round, Ottawa 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 -3°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 May and least likely around October. 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.
Ottawa weather in winterDecember to February
High 5°CLow -1°CRain 25%
Winter in Ottawa has typical daily highs of about 5°C and lows of about -1°C, with a 25% chance of rain on a given day.
Ottawa weather in springMarch to May
High 17°CLow 10°CRain 33%
Spring in Ottawa has typical daily highs of about 17°C and lows of about 10°C, with a 33% chance of rain on a given day.
Ottawa weather in summerJune to August
High 29°CLow 21°CRain 30%
Summer in Ottawa has typical daily highs of about 29°C and lows of about 21°C, with a 30% chance of rain on a given day.
Ottawa weather in autumnSeptember to November
High 19°CLow 11°CRain 26%
Autumn in Ottawa has typical daily highs of about 19°C and lows of about 11°C, with a 26% chance of rain on a given day.
When is the rainy season in Ottawa?
Ottawa has no sharply defined rainy season: the chance of rain on a given day runs from 22% in October, the driest month, to 35% in May, the wettest.
What time of year is Ottawa windiest?
Winds in Ottawa are highest in April, averaging 5.0 m/s (18 km/h), and lightest in July, at 3.1 m/s (11 km/h). The prevailing wind is from the SW.
What is the average temperature in Ottawa year round?
The average temperature in Ottawa 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 -3°C.