Annual mean 9°C · wettest around February · prevailing wind SW
Warmest
18.4 °C
Coldest
4.8 °C
Wettest
46%
Windiest
6.4 m/s
Prevailing
SW
5.1 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
never good
never good
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 Dumbarton over the whole year is 9°C. July is the hottest month, with highs of about 17°C; January is the coldest, with lows of about 4°C. Dumbarton has no sharply defined rainy season: the chance of rain on a given day runs from 21% in April, the driest month, to 39% in February, the wettest. Winds in Dumbarton are highest in February, averaging 5.4 m/s (19 km/h), and lightest in July, at 3.8 m/s (14 km/h). The prevailing wind is from the SW. The clearest skies in Dumbarton come in April, when the sky is typically 58% covered; December is the cloudiest month, at 72%.
Month by month Dumbarton 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
5°C
4°C
0°C
33%
69%
4.6 m/s
0
0
8
February
6°C
4°C
1°C
39%
69%
5.4 m/s
0
0
10
March
8°C
4°C
3°C
29%
67%
4.5 m/s
1
0
21
April
11°C
5°C
6°C
21%
58%
4.2 m/s
3
0
42
May
14°C
9°C
10°C
23%
60%
3.9 m/s
19
0
71
June
16°C
12°C
13°C
23%
65%
4.1 m/s
36
2
77
July
17°C
13°C
15°C
23%
68%
3.8 m/s
50
2
81
August
17°C
13°C
14°C
30%
66%
3.9 m/s
44
1
79
September
15°C
11°C
12°C
27%
64%
4.0 m/s
26
1
76
October
12°C
9°C
8°C
35%
68%
4.5 m/s
2
0
56
November
8°C
5°C
4°C
32%
66%
4.1 m/s
0
0
27
December
6°C
5°C
1°C
37%
72%
4.6 m/s
0
0
12
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 Dumbarton weather by season
Year round, Dumbarton has days of about 5°C at their warmest in January, its coolest month, and 17°C in July, its warmest; the coolest hours of the day run from 4°C to 13°C through the year, and the average temperature over the year is 9°C around the clock. Rain is most likely around February and least likely around April. 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.
Dumbarton weather in winterDecember to February
High 6°CLow 4°CRain 37%
Winter in Dumbarton has typical daily highs of about 6°C and lows of about 4°C, with a 37% chance of rain on a given day.
Dumbarton weather in springMarch to May
High 11°CLow 6°CRain 24%
Spring in Dumbarton has typical daily highs of about 11°C and lows of about 6°C, with a 24% chance of rain on a given day.
Dumbarton weather in summerJune to August
High 17°CLow 12°CRain 25%
Summer in Dumbarton has typical daily highs of about 17°C and lows of about 12°C, with a 25% chance of rain on a given day.
Dumbarton weather in autumnSeptember to November
High 12°CLow 8°CRain 31%
Autumn in Dumbarton has typical daily highs of about 12°C and lows of about 8°C, with a 31% chance of rain on a given day.
When is the rainy season in Dumbarton?
Dumbarton has no sharply defined rainy season: the chance of rain on a given day runs from 21% in April, the driest month, to 39% in February, the wettest.
What time of year is Dumbarton windiest?
Winds in Dumbarton are highest in February, averaging 5.4 m/s (19 km/h), and lightest in July, at 3.8 m/s (14 km/h). The prevailing wind is from the SW.
What is the average temperature in Dumbarton year round?
The average temperature in Dumbarton over the whole year is 9°C. July is the hottest month, with highs of about 17°C; January is the coldest, with lows of about 4°C.