Portsmouth weather in March

In March, Portsmouth sees average daytime highs of 41°F and overnight lows near 30°F, with 4.5 in of precipitation across 11.2 wet days and about 11.6 hours of daylight. It is the 9th-warmest and 2nd-wettest month of the year here.

Highs climb over the month, from about 38°F in the first days to 45°F by the end. The sky is clear or mostly clear about 28% of the time in March, and the air most often feels dry.

Daylight stretches from about 10 h 54 min at the start of March to 12 h 24 min by month's end. Set against the rest of the year, March is Portsmouth's 9th-clearest and 4th-windiest month. For the whole year in context, see Portsmouth's year-round climate.

Daytime high
41°
9th warmest
Overnight low
30°
4th coldest
Precipitation
4.5 in
11.2 wet days
Daylight
11 h 36 min
6:04 AM – 5:42 PM
Cloud cover
62%
9th clearest
Wind
11 mph
4th windiest
Solar energy
3.96 kWh/m²
Travel score
0.2
out of 10

Portsmouth is city in Rockingham County, New Hampshire, United States.

Density
494/km²
people per km²
Founded
1630

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in March

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 38°F in the first days to 45°F by the end.

A typical March day in Portsmouth reaches about 41°F in the afternoon and slips back to 30°F overnight — a 11°F spread between the day's warmth and the night's chill. On most days the high lands between 32°F and 51°F. Set against its neighbours, March runs about 6°F warmer than February and about 10°F cooler than April.

20°40°60°151015202531
Avg high (°F)Avg low (°F)
13826
23826
33826
43826
53827
63827
73927
83927
93928
103928
114028
124028
134029
144029
154029
164029
174130
184130
194130
204231
214231
224231
234332
244332
254333
264433
274433
284434
294534
304535
314635

How March really feels in Portsmouth

Once humidity and wind are folded in, March averages 0 days that feel above 90°F and 31 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
31
wind chill below the day's low

The story in March is cold — wind chill drags the overnight "feels like" below the raw low.

Portsmouth weather by month

How March compares with the rest of the year at a glance. March is the 9th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan34° / 22°3.69.96.79.20.0
Feb35° / 23°3.49.1610.20.0
Mar41° / 30°4.511.25.211.60.2
Apr51° / 40°4.210.61.313.12.4
May60° / 49°3.310.5014.44.7
Jun69° / 58°3.610.6015.16.3
Jul75° / 65°3.110.6014.96.9
Aug74° / 64°3.28.8013.87.2
Sep68° / 57°3.48.5012.36.6
Oct58° / 47°4.49.90.210.84.5
Nov48° / 37°3.89.71.29.51.8
Dec39° / 28°4.610.84.98.90.1

Cloud cover in March

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 28% of the time in March.

Beyond those clear spells, partly cloudy skies cover about 15% of March, with mostly cloudy or overcast conditions the remaining 57%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14258
24258
34159
44159
54159
64060
74060
84060
94159
104159
114258
124258
134357
144357
154456
164456
174456
184555
194555
204456
214456
224456
234555
244555
254456
264456
274357
284258
294258
304258
314159

Chance of precipitation in March

Any precipitationSnow

Portsmouth gets around 4.5 in of rain and snow over 11.2 wet days in March. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 36% and peaks near 38% on the wettest days, and about 5 days bring snow.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
13520
23520
33620
43620
53620
63720
73719
83719
93719
103719
113718
123718
133718
143618
153617
163617
173617
183517
193516
203516
213515
223515
233614
243614
253613
263713
273713
283712
293811
303811
313810

Humidity in March

DryComfortableHumidMuggyOppressiveMiserable

Most of March feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, March lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100
31100

Wind in March

Winds average 11 mph in March.

Across March, daily wind ranges from about 10 mph on the calmest days to 11 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
111light breeze
211light breeze
311light breeze
411light breeze
511light breeze
611light breeze
711light breeze
811light breeze
911light breeze
1011light breeze
1111light breeze
1211light breeze
1311light breeze
1411light breeze
1511light breeze
1611light breeze
1711light breeze
1811light breeze
1911light breeze
2011light breeze
2111light breeze
2211light breeze
2310light breeze
2410light breeze
2510light breeze
2610light breeze
2710light breeze
2810light breeze
2910light breeze
3010light breeze
3110light breeze

Sunrise & sunset in March

DaylightNight

Daylight runs from about 10 h 54 min at the start of March to 12 h 24 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 90 minutes over March. Sunrise moves from 6:29 AM to 5:36 AM, and sunset from 5:23 PM to 6:00 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
110.96:295:23
210.96:285:24
311.06:265:26
411.06:245:27
511.16:235:28
611.16:215:29
711.26:195:31
811.26:185:32
911.36:165:33
1011.36:145:34
1111.46:125:36
1211.46:115:37
1311.56:095:38
1411.56:075:39
1511.66:055:41
1611.66:045:42
1711.76:025:43
1811.76:005:44
1911.85:585:45
2011.85:565:47
2111.95:555:48
2211.95:535:49
2312.05:515:50
2412.05:495:51
2512.15:475:53
2612.15:455:54
2712.25:445:55
2812.25:425:56
2912.35:405:57
3012.35:385:58
3112.45:366:00

Solar energy in March

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in March, about 3.96 kWh/m².

For context, solar energy here swings from a low near 1.54 kWh/m² to a high of 6.11 kWh/m² in July across the year — March's 3.96 kWh/m² falls in the middle.

012345151015202531
Solar energy (kWh/m²)Level
13.3Moderate
23.4Moderate
33.4Moderate
43.4Moderate
53.5Moderate
63.5Moderate
73.6Moderate
83.6Moderate
93.7Moderate
103.7Moderate
113.8Moderate
123.8Moderate
133.9Moderate
143.9Moderate
154.0Moderate
164.0Bright
174.1Bright
184.1Bright
194.2Bright
204.2Bright
214.2Bright
224.3Bright
234.3Bright
244.3Bright
254.3Bright
264.4Bright
274.4Bright
284.4Bright
294.4Bright
304.5Bright
314.5Bright
Planning a trip in March

Hazard calendar for Portsmouth

In seasonPeak

None of Portsmouth's seasonal hazards are active in March. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Portsmouth sits in the Atlantic hurricane belt; the season peaks August–October.

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

Is March a good time to visit Portsmouth?

Our two travel scores rate March for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

0.2
Sightseeing
9th-best month of the year
0.0
Beach & pool
8th-best month of the year

March is a weaker month for outdoor sightseeing in Portsmouth.

What to pack for Portsmouth in March

From March's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In March, Portsmouth sees daytime highs around 41°F and nights near 30°F. Pack a warm layer. Worth having: a heavy coat and rain gear. About 11 days see rain.

a warm layera heavy coatrain gear

Sea temperature near Portsmouth in March

The nearest coast averages about 38°F in March — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in August at about 65°F and coldest in March near 38°F.

The water stays below 68°F all year — cool enough that most swimmers want a wetsuit.

40°50°60°70°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshing
Sea temperature (°F)Comfort
Jan42Bracing
Feb39Bracing
Mar38Bracing
Apr42Bracing
May49Bracing
Jun57Bracing
Jul63Cool
Aug65Cool
Sep62Cool
Oct55Bracing
Nov49Bracing
Dec45Bracing

UV index in Portsmouth in March

LowModerateHighVery highExtreme

Clear-sky midday UV in March peaks around 4 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Portsmouth peaks around July 10 at about 7 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 23 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighHighModerateModerateLowJul 10UV 7Dec 23UV 1
UV index (midday)Level
Jan1Low
Feb2Moderate
Mar4Moderate
Apr5High
May7High
Jun7High
Jul7Very high
Aug4Moderate
Sep6High
Oct3Moderate
Nov2Moderate
Dec1Low
Location & terrain

Where is Portsmouth?

Portsmouth sits at 43.1°N, 70.8°W, 20 ft above sea level, in United States. The nearest listed city is Dover, 9.9 mi away.

Topography around Portsmouth

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Portsmouth.

Within 2 miles, the terrain around Portsmouth has only modest variations in elevation — a maximum elevation change of 161 ft around an average of 39 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 430 ft; within 50 miles, large variations in elevation — a maximum elevation change of 2,454 ft.

The land around Portsmouth is covered by trees (45%), water (22%) and artificial surfaces (21%) within 2 miles, trees (49%) and water (36%) within 10 miles, and trees (61%) and water (32%) within 50 miles.

2 miles
161 ft
10 miles
430 ft
50 miles
2,454 ft
treesgrasslandartificial surfaceswaterwetland
March weather nearby: Dover 9.9 mi · Amesbury 17 mi · Rochester 19 mi · Newburyport 19 mi · Sanford 25 mi · Haverhill 26 mi · Salem 30 mi · Derry Village 31 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Portsmouth (43.077°, -70.7577°, elevation 20 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).