Portsmouth weather in May

In May, Portsmouth sees average daytime highs of 57°F and overnight lows near 51°F, with 3.9 in of rain across 10.9 wet days and about 14.3 hours of daylight. It is the 6th-warmest and 8th-wettest month of the year here.

Highs climb over the month, from about 54°F in the first days to 61°F by the end. The sky is clear or mostly clear about 27% of the time in May, and the air most often feels dry.

Daylight stretches from about 13 h 48 min at the start of May to 14 h 48 min by month's end. Set against the rest of the year, May is Portsmouth's 12th-clearest and 8th-windiest month. For the whole year in context, see Portsmouth's year-round climate.

Daytime high
57°
6th warmest
Overnight low
51°
7th coldest
Rainfall
3.9 in
10.9 wet days
Daylight
14 h 18 min
4:31 AM – 6:51 PM
Cloud cover
63%
12th clearest
Wind
11 mph
8th windiest
Solar energy
5.67 kWh/m²
Travel score
4.0
out of 10

Portsmouth is town in Newport County, Rhode Island, USA.

Founded
1638

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 54°F in the first days to 61°F by the end.

A typical May day in Portsmouth reaches about 57°F in the afternoon and slips back to 51°F overnight — a 6°F spread between the day's warmth and the night's chill. On most days the high lands between 52°F and 63°F. Set against its neighbours, May runs about 8°F warmer than April and about 9°F cooler than June.

40°50°60°70°151015202531
Avg high (°F)Avg low (°F)
15347
25347
35447
45448
55448
65548
75549
85549
95549
105549
115650
125650
135650
145650
155751
165751
175751
185851
195852
205852
215952
225953
235953
246053
256054
266054
276054
286155
296155
306155
316256

How May really feels in Portsmouth

Once humidity and wind are folded in, May averages 0 days that feel above 90°F and 0 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
0
wind chill below the day's low

May sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Portsmouth weather by month

How May compares with the rest of the year at a glance. May is the 6th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan38° / 28°4.410.64.59.30.0
Feb38° / 29°3.89.63.910.30.0
Mar42° / 34°5.110.93.611.70.3
Apr49° / 42°4.611.40.613.12.0
May57° / 51°3.910.9014.34.0
Jun66° / 60°3.79.30156.1
Jul73° / 67°3.08.9014.77.0
Aug73° / 68°3.68.8013.77.1
Sep68° / 62°4.18.8012.36.6
Oct60° / 53°5.1100.110.95.0
Nov51° / 43°4.59.70.49.72.7
Dec44° / 35°5.211.52.990.6

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 27% of the time in May, the cloudiest month of the year.

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

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14357
24357
34357
44357
54159
64159
74258
84258
94159
104159
114159
124159
134159
144159
154159
164159
174159
184258
194258
204258
214357
224357
234456
244555
254555
264555
274654
284555
294555
304654
314654

Chance of precipitation in May

Any precipitation

Portsmouth gets around 3.9 in of rain over 10.9 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 35% and peaks near 38% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%40%50%151015202531
Rain chance (%)
138
237
337
437
537
637
737
837
938
1038
1138
1238
1338
1438
1538
1638
1738
1837
1937
2036
2135
2234
2333
2432
2532
2631
2731
2830
2930
3030
3130

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the dry band about 87% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)
19910
29910
39910
49910
59820
69820
79820
89820
99730
109730
119730
129640
139550
149550
159460
169370
179280
189091
1988111
2086122
2184142
2282153
2379174
2476195
2574215
2672226
2769247
2867258
2964279
30622810
31602911

Wind in May

Winds average 11 mph in May.

Across May, daily wind ranges from about 11 mph on the calmest days to 12 mph at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (mph)Feels
112light breeze
212light breeze
312light breeze
412light 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
2311light breeze
2411light breeze
2511light breeze
2611light breeze
2711light breeze
2811light breeze
2911light breeze
3011light breeze
3111light breeze

Sunrise & sunset in May

DaylightNight

Daylight runs from about 13 h 48 min at the start of May to 14 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 60 minutes over May. Sunrise moves from 4:49 AM to 4:20 AM, and sunset from 6:35 PM to 7:05 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.84:496:35
213.84:486:36
313.94:466:37
413.94:456:39
513.94:446:40
614.04:436:41
714.04:416:42
814.04:406:43
914.14:396:44
1014.14:386:45
1114.24:376:46
1214.24:356:47
1314.24:346:48
1414.34:336:49
1514.34:326:50
1614.34:316:51
1714.44:306:52
1814.44:296:53
1914.44:286:54
2014.54:276:55
2114.54:276:56
2214.54:266:57
2314.64:256:58
2414.64:246:59
2514.64:237:00
2614.64:237:01
2714.74:227:02
2814.74:217:03
2914.74:217:04
3014.74:207:04
3114.84:207:05

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.67 kWh/m².

For context, solar energy here swings from a low near 1.64 kWh/m² to a high of 6.12 kWh/m² in July across the year — May's 5.67 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.4Bright
25.4Bright
35.4Bright
45.4Bright
55.4Bright
65.4Bright
75.4Bright
85.5Bright
95.5Bright
105.5Bright
115.5Bright
125.5Bright
135.6Bright
145.6Bright
155.6Bright
165.7Bright
175.7Bright
185.7Bright
195.7Bright
205.8Bright
215.8Bright
225.8Bright
235.8Bright
245.9Bright
255.9Bright
265.9Bright
275.9Bright
285.9Bright
295.9Bright
305.9Bright
316.0Bright
Planning a trip in May

Hazard calendar for Portsmouth

In seasonPeak

None of Portsmouth's seasonal hazards are active in May. 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 May a good time to visit Portsmouth?

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

4.0
Sightseeing
6th-best month of the year
0.2
Beach & pool
6th-best month of the year

May is a reasonable time to visit Portsmouth for sightseeing.

What to pack for Portsmouth in May

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

In May, Portsmouth sees daytime highs around 57°F and nights near 51°F. Worth packing: a warm layer, rain gear and sun protection. About 11 days see rain.

a warm layerrain gearsun protection

Sea temperature near Portsmouth in May

The nearest coast averages about 51°F in May — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 17 mi away) is warmest in August at about 69°F and coldest in February near 39°F.

It's comfortable for a long swim from Jul 26 to Aug 30 — about 1.2 months when the water holds above 68°F.

40°50°60°70°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarm
Sea temperature (°F)Comfort
Jan43Bracing
Feb39Bracing
Mar40Bracing
Apr44Bracing
May51Bracing
Jun60Cool
Jul67Cool
Aug69Refreshing
Sep67Cool
Oct61Cool
Nov55Bracing
Dec49Bracing

UV index in Portsmouth in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 7 — 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 June 23 at about 8 (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.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 23UV 8Dec 23UV 1
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr5High
May7Very high
Jun8Very high
Jul8Very high
Aug5High
Sep6High
Oct3Moderate
Nov2Moderate
Dec1Low
Location & terrain

Where is Portsmouth?

Portsmouth sits at 41.6°N, 71.3°W, 141 ft above sea level, in United States. The nearest listed city is Middletown, 4.3 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 292 ft around an average of 66 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 358 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,181 ft.

The land around Portsmouth is covered by water (44%), trees (27%) and grassland (20%) within 2 miles, water (44%) and trees (36%) within 10 miles, and trees (50%) and water (43%) within 50 miles.

2 miles
292 ft
10 miles
358 ft
50 miles
1,181 ft
treesgrasslandcroplandartificial surfaceswaterwetland
May weather nearby: Middletown 4.3 mi · Bristol 5.0 mi · Newport 8.7 mi · Fall River 8.7 mi · Barrington 9.9 mi · Swansea 11 mi · Warwick 11 mi · North Kingstown 12 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 (41.6023°, -71.2503°, elevation 141 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).