Weather in Portsmouth

14-day forecast · updated today, Thursday, October 29, at 12:01 am (EDT)

Now · clear 46 °F

Feels like: 40 °F
Low / high: 45 / 64 °F
Rain: 1%
Wind: 6 mph SSW

↘ 30.34 inHg · falling

Today in Portsmouth: clear sky, 45 °F to 64 °F, with a 1% chance of rain and a light breeze from the south-southwest (6 mph). Tomorrow, partly cloudy, 49 °F to 67 °F and a 8% chance of rain. The warmest day of the week is Friday 30, at 67 °F. Next likely rain: Thursday 5 (32%).

Measured now at the airport

N Kingston/Quonset (KOQU), 8.3 mi away · 26 min ago

Visibility—

WeatherNothing to note

Temperature48 °F

Wind3 mph from the southwest

It's what the airport's weather station measured, not a forecast: on the coast, wind and fog can be different. Airports report every 30 or 60 minutes.

Airport METAR report, via NOAA's Aviation Weather Center (aviationweather.gov). Sources and licenses

Temperatures for the next 14 days

64° 45°
Today
67° 49°
Fri 30
55° 42°
Sat 31
58° 40°
Sun 1
63° 47°
Mon 2
61° 49°
Tue 3
62° 51°
Wed 4
63° 53°
Thu 5
62° 53°
Fri 6
58° 48°
Sat 7
57° 42°
Sun 8
54° 37°
Mon 9
55° 40°
Tue 10
57° 46°
Wed 11

Day by day

Day	Sky	Low / high	Rain	Max wind	Max wave	High tides	Model
Today · 29	Clear sky	45 / 64 °F	1%	13 mph SW	1.4 ft	10:57 am · 11:31 pm	HRRR + NBM
Fri 30	Partly cloudy	49 / 67 °F	8%	12 mph W	1.4 ft	11:56 am	NBM
Sat 31	Partly cloudy	42 / 55 °F	0%	10 mph NNW	1.0 ft	12:34 am · 12:59 pm	NBM
Sun 1	Partly cloudy	40 / 58 °F	1%	7 mph WSW	0.7 ft	1:38 am · 1:01 pm	NBM
Mon 2	Overcast	47 / 63 °F	5%	9 mph WSW	0.7 ft	1:39 am · 2:01 pm	NBM
Tue 3	Overcast	49 / 61 °F	8%	10 mph ENE	1.0 ft	2:39 am · 3:01 pm	NBM
Wed 4	Overcast	51 / 62 °F	20%	11 mph SE	1.4 ft	3:43 am · 4:06 pm	NBM
Thu 5	Overcast	53 / 63 °F	32% · 0.40 in	12 mph ESE	1.6 ft	4:44 am · 5:05 pm	NBM
Fri 6	Heavy drizzle	53 / 62 °F	40% · 0.54 in	11 mph ESE	1.5 ft	5:34 am · 5:52 pm	NBM
Sat 7	Rain	48 / 58 °F	34% · 0.27 in	11 mph NNW	—	6:14 am · 6:31 pm	NBM
Sun 8	Light drizzle	42 / 57 °F	17% · 0.12 in	10 mph NNW	—	6:50 am · 7:08 pm	NBM + ECMWF
Mon 9	Clear sky	37 / 54 °F	18%	5 mph NW	—	7:24 am · 7:44 pm	ECMWF
Tue 10	Overcast	40 / 55 °F	15%	7 mph NE	—	8:00 am · 8:23 pm	ECMWF
Wed 11	Overcast	46 / 57 °F	16%	7 mph SE	—	8:40 am · 9:06 pm	ECMWF

Each hour comes from the best model for this spot: HRRR until Thursday 29 7:00 pm; then NBM until Sunday 8 8:00 pm; then ECMWF until Thursday 12 10:00 am; then GFS.

Each day comes from the best model covering this spot: regional ones first (HRRR and NBM in the U.S., AROME, ICON-EU), then ECMWF; day 16, NOAA GFS. Waves: Météo-France up to day 10, then ECMWF WAM, coarser and further offshore. High tides: our own tide calculation.

Today, every 3 hours

Time	12:00 am	3:00 am	6:00 am	9:00 am	12:00 pm	3:00 pm	6:00 pm	9:00 pm
Sky	Clear	Clear	Clear	Clear sky	Clear sky	Clear sky	Clear	Clear
Temperature	46°	46°	45°	53°	63°	63°	57°	57°
Chance of rain	0%	0%	0%	0%	0%	1%	0%	0%
Rain	0.00 in	0.00 in	0.00 in	0.00 in	0.00 in	0.00 in	0.00 in	0.00 in
Wind (mph)	7 SSW	6 SSW	6 SW	5 SW	11 SW	12 SW	9 SW	8 SW
Humidity	77%	75%	77%	87%	65%	66%	85%	86%
UV	0	0	0	1	3	1	0	0
Model	HRRR	HRRR	HRRR	HRRR	HRRR	HRRR	HRRR	NBM

Do the models agree?

High confidence

The models agree for the next few days: the forecast is fairly solid.

What 6 forecast models say for the next few days. The closer they are, the more reliable the forecast.

HighRainWind

Do the models agree? · High
High (°F)	Today	Fri 30	Sat 31	Sun 1	Mon 2	Tue 3	Wed 4
ECMWF	63°	65°	52°	53°	63°	63°	66°
AIFS	65°	68°	54°	56°	66°	69°	70°
GFS	62°	69°	54°	57°	63°	58°	56°
ICON	64°	69°	53°	59°	67°	57°	58°
HRRR	64°	64°	—	—	—	—	—
NBM	64°	67°	55°	58°	63°	61°	62°
Confidence	high	high	high	high	high	medium	low

Do the models agree? · Rain
Rain	Today	Fri 30	Sat 31	Sun 1	Mon 2	Tue 3	Wed 4
ECMWF	0	0	0	0	0	0	0
AIFS	0	0	0	0	0	0	0
GFS	0	0.01 in	0	0	0	0	0.02 in
ICON	0	0	0	0	0	0	0
HRRR	0	0	—	—	—	—	—
NBM	0	0	0	0	0	0	0
Confidence	high	high	high	high	high	high	high

Do the models agree? · Wind
Wind (mph)	Today	Fri 30	Sat 31	Sun 1	Mon 2	Tue 3	Wed 4
ECMWF	1223	1324	1225	522	1219	1321	1324
AIFS	11	12	10	6	9	11	11
GFS	1430	1831	1427	917	1427	1024	915
ICON	1125	1127	1024	921	1024	1229	617
HRRR	1326	1629	—	—	—	—	—
NBM	1218	1218	1016	711	913	1015	1115
Confidence	high	high	high	high	high	high	high

Chance of rain from the ensemble models

Model	Today	Fri 30	Sat 31	Sun 1	Mon 2	Tue 3	Wed 4
ECMWF (51 scenarios)	0%	8%	0%	0%	4%	12%	18%
GFS (GEFS, 31 scenarios)	0%	10%	0%	0%	16%	26%	40%
NBM (NOAA)	1%	8%	0%	1%	5%	8%	20%
Thunderstorm (NBM)	0%	2%	0%	0%	0%	1%	1%

Each model's day runs midnight to midnight local time; models that reach fewer days are left blank. Rain: daily total. Wind: the day's highest average wind and, in small type, the strongest gust. Highlighted: values that stand out from the rest. The chance of rain comes from many runs of the same model with slightly different starting data.

Outlook

How the coming weeks and months compare with what is normal for the time of year. It is a trend, not a day-by-day forecast.

Next few weeks, compared with normal: a bit warmer, normal rain and a slightly warmer sea.

Next 6 weeks

When	TemperatureTemp.	Rain	Sea	Typical high / low
Nov 2 – Nov 8Nov 2–Nov 8	Above +4.7 °F	A bit above +22%	A bit above +0.7 °F	—
Nov 9 – Nov 15Nov 9–Nov 15	A bit above +1.3 °F	Normal	A bit above +1.3 °F	—
Nov 16 – Nov 22Nov 16–Nov 22	A bit above +2.0 °F	Normal	A bit above +1.3 °F	51° / 45°
Nov 23 – Nov 29Nov 23–Nov 29	A bit above +2.2 °F	A bit above +33%	A bit above +1.3 °F	49° / 44°
Nov 30 – Dec 6Nov 30–Dec 6	A bit above +1.6 °F	A bit above +21%	A bit above +0.9 °F	47° / 41°

Coming months

When	TemperatureTemp.	Rain	Sea
November	A bit above +1.3 °F	A bit above +23%	A bit above +0.7 °F
December	Above +2.7 °F	A bit above +24%	A bit above +1.6 °F
January	Above +3.8 °F	A bit above +36%	Above +2.3 °F
February	Above +3.2 °F	A bit above +26%	Above +2.9 °F
March	Above +2.9 °F	A bit above +20%	Above +2.3 °F

Weeks: ECMWF 46-day (average of its scenarios), against the normal of the last 20 years for those dates. Months: ECMWF SEAS5. Rain: total against normal. The further ahead, the closer it gets to normal and the less detail it can give.

Portsmouth climate by monthClimate by month

Normal weather for each month (1991–2020 averages)

The best time to visit Portsmouth is from June to September: highs of 73 °F to 81 °F, about 8 rainy days a month and 7 hours of sunshine a day.

Hurricane season: from July to September, peaking in July. In the last 30 years (1996–2025), 7 tropical cyclones passed within 93 mi of Portsmouth, about 2 every 10 years. The most recent: Henri, in August 2021.

38° 22°

JanJ
39° 23°

FebF
46° 29°

MarM
55° 38°

AprA
66° 47°

MayM
74° 56°

JunJ
81° 64°

JulJ
80° 63°

AugA
73° 56°

SepS
64° 46°

OctO
53° 37°

NovN
44° 28°

DecD

Highs and lows
Monthly rainfall
Best time

Month	High	Low	Rain	Rainy daysDays	Sun (h/day)	Water	Waves	Cyclones
JanuaryJan	38°	22°	3.97 in	8	3.6	43°	2.8 ft	–
FebruaryFeb	39°	23°	3.51 in	7	5.0	39°	2.8 ft	–
MarchMar	46°	29°	4.96 in	9	5.4	40°	2.6 ft	–
AprilApr	55°	38°	4.28 in	9	6.2	44°	2.9 ft	–
MayMay	66°	47°	3.37 in	9	6.5	51°	2.4 ft	–
JuneJun	74°	56°	4.00 in	9	7.3	60°	2.2 ft	–
JulyJul	81°	64°	3.34 in	8	7.9	67°	2.3 ft	3
AugustAug	80°	63°	3.97 in	9	7.3	69°	2.2 ft	2
SeptemberSep	73°	56°	3.93 in	8	6.0	67°	2.5 ft	2
OctoberOct	64°	46°	4.57 in	8	4.7	61°	2.7 ft	–
NovemberNov	53°	37°	4.46 in	8	3.7	55°	2.7 ft	–
DecemberDec	44°	28°	4.72 in	9	3.2	49°	2.8 ft	–

Month	Water	Waves	Cyclones
Jan	43°	2.8 ft	–
Feb	39°	2.8 ft	–
Mar	40°	2.6 ft	–
Apr	44°	2.9 ft	–
May	51°	2.4 ft	–
Jun	60°	2.2 ft	–
Jul	67°	2.3 ft	3
Aug	69°	2.2 ft	2
Sep	67°	2.5 ft	2
Oct	61°	2.7 ft	–
Nov	55°	2.7 ft	–
Dec	49°	2.8 ft	–

Days: rainy days in the month. Sun: hours a day.

A normal year brings 49.10 in of rain on about 100 days and about 2,050 hours of sunshine.

Cyclones: how many tropical cyclones (tropical storms, hurricanes and typhoons) passed within 93 mi in each month from 1996 to 2025, according to IBTrACS (NOAA).

1991–2020 averages. Highs, lows and rainfall: TerraClimate; rainy days (0.04 in or more): NASA POWER (MERRA-2); sunshine hours: estimated from solar radiation; water: NOAA OISST; waves (average height): ERA5, 2011–2020. Normals are not a forecast: any given year can turn out very different. Sources and licenses

Temperature

Now46 °Ffeels like 40 °F

Tomorrow49 / 67 °F

It's 46 °F now (feels like 40 °F). Today, 45 °F to 64 °F; tomorrow, 49 °F to 67 °F.

Chance of rain

Today 1%
Fri 30 8%
Sat 31 0%
Sun 1 1%
Mon 2 5%
Tue 3 8%
Wed 4 20%

Today the chance of rain reaches 1%. The next day with likely rain is Thursday 5: 32% and 0.40 in.

No rain in the last 7 days.

Humidity and dew point

Humidity77%

Dew point39 °F

Humidity is 77% now and the dew point is 39 °F.

The dew point is the temperature at which the air becomes saturated: the higher it is, the heavier the air feels.

Visibility and fog

Now11 migood

Clouds0%

Visibility is good now (11 mi). No fog expected today.

UV index

Now0

Today's peak3moderate

Fri 30: 3 · Sat 31: 3 · Sun 1: 3

Index	Level	What to do
0–2	low	No special protection needed.
3–5	moderate	Hat, sunglasses and sunscreen around midday.
6–7	high	Sunscreen, hat and shade between 12 and 4 pm.
8–10	very high	Avoid the midday sun; reflection off the water adds to it.
11+	extreme	Avoid the sun between 11 am and 5 pm; protect yourself even if it is cloudy.

Reflection off water and sand adds radiation: protect yourself more on a boat or at the beach.

Barometric pressure

↗ Rising Anglers say fish bite less for a while
→ Steady Anglers expect normal activity
↘ Falling · now Anglers say fish feed more before the change

30.0030.2030.40 29.96

Falling now (−0.06 inHg in 3 hours). Over the next 48 hours: −0.15 inHg. Falling pressure: anglers say fish feed more before the change. Fast changes, either way, tend to affect fishing.

Air and pollen

Air qualityGood · 48

Saharan dustNo

Previous days

The weather over the last 30 days, as the models analyzed it. Tap a day to see it hour by hour.

Day	Sky	Low / high	Max wind
Wed 28	Overcast	36 / 55 °F	7 mph NW
Tue 27	Partly cloudy	46 / 57 °F	10 mph N
Mon 26	Mainly clear	44 / 65 °F	10 mph WSW
Sun 25	Partly cloudy	35 / 61 °F	7 mph SSW
Sat 24	Mainly clear	35 / 57 °F	5 mph NW
Fri 23	Clear sky	44 / 55 °F	13 mph N
Thu 22	Overcast	48 / 60 °F	16 mph N

Show all 30 days

Day	Sky	Low / high	Rain	Max wind
Wed 21	Overcast	49 / 55 °F	0	18 mph NNE
Tue 20	Overcast	44 / 61 °F	0	15 mph NNE
Mon 19	Partly cloudy	41 / 60 °F	0	9 mph NE
Sun 18	Clear sky	37 / 55 °F	0	8 mph NNE
Sat 17	Drizzle	42 / 62 °F	0.19 in	13 mph NNW
Fri 16	Rain	52 / 66 °F	0.80 in	15 mph S
Thu 15	Partly cloudy	53 / 63 °F	0	13 mph N
Wed 14	Overcast	62 / 77 °F	0	12 mph W
Tue 13	Light rain	56 / 62 °F	0.39 in	11 mph SE
Mon 12	Drizzle	53 / 68 °F	0.07 in	16 mph N
Sun 11	Rain	50 / 59 °F	1.03 in	13 mph E
Sat 10	Overcast	50 / 63 °F	0	9 mph NW
Fri 9	Overcast	53 / 67 °F	0	13 mph W
Thu 8	Light drizzle	58 / 71 °F	0.01 in	11 mph WSW
Wed 7	Mainly clear	45 / 62 °F	0	12 mph SSW
Tue 6	Clear sky	48 / 61 °F	0	12 mph WNW
Mon 5	Light drizzle	55 / 69 °F	0.01 in	15 mph WNW
Sun 4	Light drizzle	52 / 66 °F	0.04 in	9 mph NE
Sat 3	Overcast	55 / 69 °F	0	10 mph NNE
Fri 2	Light drizzle	66 / 75 °F	0.01 in	13 mph SW
Thu 1	Overcast	60 / 72 °F	0	12 mph SSW
Wed 30	Overcast	60 / 66 °F	0	7 mph SW
Tue 29	Overcast	57 / 66 °F	0	9 mph NW

These are the models at the start of each day (ECMWF and GFS; waves from Météo-France), not readings from a weather station: there can be differences at specific spots.

Questions about the weather in PortsmouthQuestions

What's the weather like today in Portsmouth?

Clear sky, from 45 °F to 64 °F, with a light breeze from the south-southwest (6 mph) and a 1% chance of rain.

Will it rain tomorrow in Portsmouth?

On Friday 30 the chance of rain is 8% (0.00 in): partly cloudy.

How warm will it be this week?

Between a low of 40 °F and a high of 67 °F; the warmest day, Friday 30.

What's the UV index today?

It reaches 3 (moderate). Hat, sunglasses and sunscreen around midday.

Is the pressure rising or falling?

It's 30.34 inHg and falling: −0.08 inHg over the last 24 hours.

When is the best time to visit Portsmouth?

The best time to visit Portsmouth is from June to September: highs of 73 °F to 81 °F, about 8 rainy days a month and 7 hours of sunshine a day.

What is the weather like in Portsmouth in October?

In October, Portsmouth normally sees highs of 64 °F and lows of 46 °F, with about 8 rainy days (4.57 in for the month) and 5 hours of sunshine a day. The sea is around 61 °F. These are 1991–2020 averages.

What are the warmest and wettest months in Portsmouth?

The warmest is July, with average highs of 81 °F, and the coldest January, with lows of 22 °F. The wettest is March (4.96 in) and the driest, July.

When is hurricane season in Portsmouth?

Hurricane season: from July to September, peaking in July. In the last 30 years (1996–2025), 7 tropical cyclones passed within 93 mi of Portsmouth, about 2 every 10 years. The most recent: Henri, in August 2021.

More about Portsmouth today

Weather near Portsmouth

Only places with a different forecast: spots a few miles apart share the same model cell and wouldn't add anything.

Learn more

Weather: Open-Meteo, CC BY 4.0, with the best model for each spot and lead time (NOAA HRRR and NBM in the U.S., Météo-France AROME, DWD ICON-EU, ECMWF IFS and NOAA GFS); ECMWF grid point 10 mi away. The comparison also uses ICON (DWD), AIFS (ECMWF) and ARPEGE (Météo-France). Outlook: ECMWF 46-day and SEAS5. Chance of rain from ensemble models (ECMWF, GEFS and NBM). UV, air quality and pollen: CAMS (Copernicus).

Forecast from Open-Meteo (CC BY 4.0) with models from ECMWF, NOAA, Météo-France, DWD, Copernicus Marine and CAMS. Updated at 12:01 am (local time).

Spotted a mistake? Tell us · Where the weather and sea data come from