Portsmouth weather by month

Check out Portsmouth weather averages by month. Compare detailed monthly climate statistics including temperature, rainfall and sunshine figures.

Temperature in Portsmouth (°F)

  Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Max temperature (daytime)
34°F maximum daytime temperature in January in Portsmouth34
36°F maximum daytime temperature in February in Portsmouth36
45°F maximum daytime temperature in March in Portsmouth45
55°F maximum daytime temperature in April in Portsmouth55
66°F maximum daytime temperature in May in Portsmouth66
77°F maximum daytime temperature in June in Portsmouth77
82°F maximum daytime temperature in July in Portsmouth82
81°F maximum daytime temperature in August in Portsmouth81
73°F maximum daytime temperature in September in Portsmouth73
63°F maximum daytime temperature in October in Portsmouth63
50°F maximum daytime temperature in November in Portsmouth50
37°F maximum daytime temperature in December in Portsmouth37
Min temperature (night-time)
12°F minimum night-time temperature in January in Portsmouth12
16°F minimum night-time temperature in February in Portsmouth16
25°F minimum night-time temperature in March in Portsmouth25
34°F minimum night-time temperature in April in Portsmouth34
43°F minimum night-time temperature in May in Portsmouth43
52°F minimum night-time temperature in June in Portsmouth52
59°F minimum night-time temperature in July in Portsmouth59
57°F minimum night-time temperature in August in Portsmouth57
50°F minimum night-time temperature in September in Portsmouth50
39°F minimum night-time temperature in October in Portsmouth39
30°F minimum night-time temperature in November in Portsmouth30
19°F minimum night-time temperature in December in Portsmouth19
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
Sea temperature
41°F sea temperature in January in Portsmouth41
39°F sea temperature in February in Portsmouth39
37°F sea temperature in March in Portsmouth37
41°F sea temperature in April in Portsmouth41
48°F sea temperature in May in Portsmouth48
55°F sea temperature in June in Portsmouth55
63°F sea temperature in July in Portsmouth63
64°F sea temperature in August in Portsmouth64
61°F sea temperature in September in Portsmouth61
54°F sea temperature in October in Portsmouth54
48°F sea temperature in November in Portsmouth48
45°F sea temperature in December in Portsmouth45

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

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
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

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 (inches)
3.4 inches monthly rainfall in January in Portsmouth3.4
3.5 inches monthly rainfall in February in Portsmouth3.5
3.4 inches monthly rainfall in March in Portsmouth3.4
3.6 inches monthly rainfall in April in Portsmouth3.6
3.4 inches monthly rainfall in May in Portsmouth3.4
3.1 inches monthly rainfall in June in Portsmouth3.1
3.0 inches monthly rainfall in July in Portsmouth3.0
2.8 inches monthly rainfall in August in Portsmouth2.8
3.4 inches monthly rainfall in September in Portsmouth3.4
3.7 inches monthly rainfall in October in Portsmouth3.7
4.9 inches monthly rainfall in November in Portsmouth4.9
4.2 inches monthly rainfall in December in Portsmouth4.2

More about Portsmouth

Portsmouth by month

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

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The climate guide for New Hampshire (Portsmouth) 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.

What's the climate like in Portsmouth?

Portsmouth has a cold climate with warm summers and some rainfall in all months.

Metric (°C)  |  Imperial (°F)

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Tropical storm risk: Portsmouth, New Hampshire hurricane season

% of month affected by tropical storms
0
0
0
0
0
0
0
1.2%
1.8%
0
0
0
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

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More about the USA

Compare Portsmouth with the USA

Below the Portsmouth chart shows average maximum daytime temperature for Portsmouth, New Hampshire, USA and the USA (Washington).

Maximum daytime temperature (°F)

Portsmouth, New Hampshire, USA
USA (Washington)
34
41
36
45
45
55
55
66
66
75
77
84
82
88
81
86
73
79
63
68
50
57
37
46
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Metric (°C)  |  Imperial (°F)

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