Dumbarton weather
The Dumbarton weather guide shows monthly weather averages (including daytime and night-time temperatures, rainfall and hours of sunshine) for holidays in Dumbarton, West Dunbartonshire, Scotland in 2026/2027.
Dumbarton weather averages
Check the Dumbarton weather averages for each month of the year including maximum daytime and minimum night-time temperatures, monthly rainfall, number of days with rain and average daily hours of sunshine for Dumbarton, West Dunbartonshire, Scotland.
Dumbarton weather by month
Check the weather for Dumbarton, West Dunbartonshire, Scotland for a particular month by selecting from the list below. This gives the best indication of what to expect from the weather months in advance.
Dumbarton weather in January
The average maximum daytime temperature in Dumbarton in January is a cold 6°C (43°F), while the average minimum night-time temperature is a cold 2°C (36°F). You can expect on average 1 hours of sunshine a day in Dumbarton during January.
- 6°C max day temperature
6 - 1 hour of sunshine per day
1 - 22 days with some rainfall
22 - 2°C min night temperature
2 - 171 mm of monthly rainfall
171
On average 171 mm (6.7 inches) of rain normally falls in Dumbarton during January with rain falling on 22 days of the month.
Dumbarton weather in February
The average maximum daytime temperature in Dumbarton in February is a cold 6°C (43°F), while the average minimum night-time temperature is a cold 2°C (36°F). You can expect on average 2 hours of sunshine a day in Dumbarton during February.
- 6°C max day temperature6
- 2 hours of sunshine per day
2 - 19 days with some rainfall
19 - 2°C min night temperature2
- 118 mm of monthly rainfall
118
On average 118 mm (4.6 inches) of rain normally falls in Dumbarton during February with rain falling on 19 days of the month.
Dumbarton weather in March
The average maximum daytime temperature in Dumbarton in March is a cool 8°C (46°F), while the average minimum night-time temperature is a cold 2°C (36°F). You can expect on average 3 hours of sunshine a day in Dumbarton during March.
- 8°C max day temperature
8 - 3 hours of sunshine per day
3 - 20 days with some rainfall20
- 2°C min night temperature2
- 131 mm of monthly rainfall
131
On average 131 mm (5.2 inches) of rain normally falls in Dumbarton during March with rain falling on 20 days of the month.
Dumbarton weather in April
The average maximum daytime temperature in Dumbarton in April is a cool 11°C (52°F), while the average minimum night-time temperature is a cold 4°C (39°F). You can expect on average 5 hours of sunshine a day in Dumbarton during April.
- 11°C max day temperature11
- 5 hours of sunshine per day
5 - 16 days with some rainfall
16 - 4°C min night temperature4
- 84 mm of monthly rainfall
84
On average 84 mm (3.3 inches) of rain normally falls in Dumbarton during April with rain falling on 16 days of the month.
Dumbarton weather in May
The average maximum daytime temperature in Dumbarton in May is a comfortable 14°C (57°F), while the average minimum night-time temperature is a cold 6°C (43°F). You can expect on average 6 hours of sunshine a day in Dumbarton during May.
- 14°C max day temperature
14 - 6 hours of sunshine per day
6 - 16 days with some rainfall16
- 6°C min night temperature6
- 75 mm of monthly rainfall
75
On average 75 mm (3 inches) of rain normally falls in Dumbarton during May with rain falling on 16 days of the month.
Dumbarton weather in June
The average maximum daytime temperature in Dumbarton in June is a comfortable 16°C (61°F), while the average minimum night-time temperature is a cool 9°C (48°F). You can expect on average 6 hours of sunshine a day in Dumbarton during June.
- 16°C max day temperature
16 - 6 hours of sunshine per day6
- 16 days with some rainfall16
- 9°C min night temperature9
- 79 mm of monthly rainfall79
On average 79 mm (3.1 inches) of rain normally falls in Dumbarton during June with rain falling on 16 days of the month.
Dumbarton weather in July
The average maximum daytime temperature in Dumbarton in July is a comfortable 18°C (64°F), while the average minimum night-time temperature is a cool 11°C (52°F). You can expect on average 5 hours of sunshine a day in Dumbarton during July.
- 18°C max day temperature
18 - 5 hours of sunshine per day5
- 17 days with some rainfall17
- 11°C min night temperature11
- 95 mm of monthly rainfall95
On average 95 mm (3.7 inches) of rain normally falls in Dumbarton during July with rain falling on 17 days of the month.
Dumbarton weather in August
The average maximum daytime temperature in Dumbarton in August is a comfortable 17°C (63°F), while the average minimum night-time temperature is a cool 11°C (52°F). You can expect on average 5 hours of sunshine a day in Dumbarton during August.
- 17°C max day temperature17
- 5 hours of sunshine per day5
- 18 days with some rainfall18
- 11°C min night temperature11
- 124 mm of monthly rainfall124
On average 124 mm (4.9 inches) of rain normally falls in Dumbarton during August with rain falling on 18 days of the month.
Dumbarton weather in September
The average maximum daytime temperature in Dumbarton in September is a comfortable 15°C (59°F), while the average minimum night-time temperature is a cool 9°C (48°F). You can expect on average 4 hours of sunshine a day in Dumbarton during September.
- 15°C max day temperature15
- 4 hours of sunshine per day
4 - 20 days with some rainfall20
- 9°C min night temperature9
- 154 mm of monthly rainfall
154
On average 154 mm (6.1 inches) of rain normally falls in Dumbarton during September with rain falling on 20 days of the month.
Dumbarton weather in October
The average maximum daytime temperature in Dumbarton in October is a cool 12°C (54°F), while the average minimum night-time temperature is a cold 7°C (45°F). You can expect on average 2 hours of sunshine a day in Dumbarton during October.
- 12°C max day temperature12
- 2 hours of sunshine per day2
- 22 days with some rainfall22
- 7°C min night temperature7
- 160 mm of monthly rainfall160
On average 160 mm (6.3 inches) of rain normally falls in Dumbarton during October with rain falling on 22 days of the month.
Dumbarton weather in November
The average maximum daytime temperature in Dumbarton in November is a cool 9°C (48°F), while the average minimum night-time temperature is a cold 4°C (39°F). You can expect on average 2 hours of sunshine a day in Dumbarton during November.
- 9°C max day temperature9
- 2 hours of sunshine per day2
- 22 days with some rainfall22
- 4°C min night temperature4
- 165 mm of monthly rainfall165
On average 165 mm (6.5 inches) of rain normally falls in Dumbarton during November with rain falling on 22 days of the month.
Dumbarton weather in December
The average maximum daytime temperature in Dumbarton in December is a cold 7°C (45°F), while the average minimum night-time temperature is a cold 3°C (37°F). You can expect on average 1 hours of sunshine a day in Dumbarton during December.
- 7°C max day temperature7
- 1 hour of sunshine per day1
- 23 days with some rainfall23
- 3°C min night temperature3
- 165 mm of monthly rainfall165
On average 165 mm (6.5 inches) of rain normally falls in Dumbarton during December with rain falling on 23 days of the month.