Portsmouth climate guide

Temperature in Portsmouth (°C)

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Max temperature (daytime)
1°C maximum daytime temperature in January in Portsmouth1
2°C maximum daytime temperature in February in Portsmouth2
7°C maximum daytime temperature in March in Portsmouth7
13°C maximum daytime temperature in April in Portsmouth13
19°C maximum daytime temperature in May in Portsmouth19
25°C maximum daytime temperature in June in Portsmouth25
28°C maximum daytime temperature in July in Portsmouth28
27°C maximum daytime temperature in August in Portsmouth27
23°C maximum daytime temperature in September in Portsmouth23
17°C maximum daytime temperature in October in Portsmouth17
10°C maximum daytime temperature in November in Portsmouth10
3°C maximum daytime temperature in December in Portsmouth3
Min temperature (night-time)
-11°C minimum night-time temperature in January in Portsmouth-11
-9°C minimum night-time temperature in February in Portsmouth-9
-4°C minimum night-time temperature in March in Portsmouth-4
1°C minimum night-time temperature in April in Portsmouth1
6°C minimum night-time temperature in May in Portsmouth6
11°C minimum night-time temperature in June in Portsmouth11
15°C minimum night-time temperature in July in Portsmouth15
14°C minimum night-time temperature in August in Portsmouth14
10°C minimum night-time temperature in September in Portsmouth10
4°C minimum night-time temperature in October in Portsmouth4
-1°C minimum night-time temperature in November in Portsmouth-1
-7°C minimum night-time temperature in December in Portsmouth-7
Sea temperature
5°C sea temperature in January in Portsmouth5
4°C sea temperature in February in Portsmouth4
3°C sea temperature in March in Portsmouth3
5°C sea temperature in April in Portsmouth5
9°C sea temperature in May in Portsmouth9
13°C sea temperature in June in Portsmouth13
17°C sea temperature in July in Portsmouth17
18°C sea temperature in August in Portsmouth18
16°C sea temperature in September in Portsmouth16
12°C sea temperature in October in Portsmouth12
9°C sea temperature in November in Portsmouth9
7°C sea temperature in December in Portsmouth7

Sunshine & Daylight in Portsmouth

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Daily hours of sunshine
Daily hours of daylight
9 hours of daylight per day in January in Portsmouth9
11 hours of daylight per day in February in Portsmouth11
12 hours of daylight per day in March in Portsmouth12
13 hours of daylight per day in April in Portsmouth13
15 hours of daylight per day in May in Portsmouth15
15 hours of daylight per day in June in Portsmouth15
15 hours of daylight per day in July in Portsmouth15
14 hours of daylight per day in August in Portsmouth14
12 hours of daylight per day in September in Portsmouth12
11 hours of daylight per day in October in Portsmouth11
10 hours of daylight per day in November in Portsmouth10
9 hours of daylight per day in December in Portsmouth9

Rainfall in Portsmouth

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Number of days with some rain
11 days with some rainfall in January in Portsmouth11
9 days with some rainfall in February in Portsmouth9
11 days with some rainfall in March in Portsmouth11
11 days with some rainfall in April in Portsmouth11
12 days with some rainfall in May in Portsmouth12
11 days with some rainfall in June in Portsmouth11
10 days with some rainfall in July in Portsmouth10
10 days with some rainfall in August in Portsmouth10
8 days with some rainfall in September in Portsmouth8
9 days with some rainfall in October in Portsmouth9
11 days with some rainfall in November in Portsmouth11
12 days with some rainfall in December in Portsmouth12
Average monthly rainfall (mm)
87 mm monthly rainfall in January in Portsmouth87
88 mm monthly rainfall in February in Portsmouth88
87 mm monthly rainfall in March in Portsmouth87
92 mm monthly rainfall in April in Portsmouth92
86 mm monthly rainfall in May in Portsmouth86
78 mm monthly rainfall in June in Portsmouth78
77 mm monthly rainfall in July in Portsmouth77
70 mm monthly rainfall in August in Portsmouth70
87 mm monthly rainfall in September in Portsmouth87
94 mm monthly rainfall in October in Portsmouth94
125 mm monthly rainfall in November in Portsmouth125
107 mm monthly rainfall in December in Portsmouth107

More climate for Portsmouth

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
UV Index (Maximum)
UV (maximum) index 1 (Low) in January in Portsmouth1
UV (maximum) index 2 (Low) in February in Portsmouth2
UV (maximum) index 3 (Moderate) in March in Portsmouth3
UV (maximum) index 5 (Moderate) in April in Portsmouth5
UV (maximum) index 7 (High) in May in Portsmouth7
UV (maximum) index 8 (Very High) in June in Portsmouth8
UV (maximum) index 8 (Very High) in July in Portsmouth8
UV (maximum) index 7 (High) in August in Portsmouth7
UV (maximum) index 6 (High) in September in Portsmouth6
UV (maximum) index 3 (Moderate) in October in Portsmouth3
UV (maximum) index 2 (Low) in November in Portsmouth2
UV (maximum) index 1 (Low) in December in Portsmouth1
Heat & Humidity
No heat & humidity in January in Portsmouth0
No heat & humidity in February in Portsmouth0
No heat & humidity in March in Portsmouth0
No heat & humidity in April in Portsmouth0
No heat & humidity in May in Portsmouth0
No heat & humidity in June in Portsmouth0
Low heat & humidity in July in PortsmouthL
Low heat & humidity in August in PortsmouthL
No heat & humidity in September in Portsmouth0
No heat & humidity in October in Portsmouth0
No heat & humidity in November in Portsmouth0
No heat & humidity in December in Portsmouth0

Note: 0 = None, L = Low, M = Moderate, H = High, VH = Very high, E = Extreme

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Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

The climate guide for Portsmouth, New Hampshire shows long term monthly weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

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Metric (°C / mm)  |  Imperial (°F / inches)

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