When to Portsmouth
Climate guide & best times to travel
Best Time to Visit
Month-by-Month Guide
January
January brings the coolest temperatures of the year with highs of 46°F and lows of 37°F. Rainfall is moderate at 3.3 inches, making it one of the wetter winter months. This is a quiet time for tourism with crisp, cool conditions requiring warm clothing.
February
February remains quite cool with temperatures reaching 47°F during the day and dropping to 36°F at night - the coldest nighttime temperatures of the year. Rainfall decreases to 2.3 inches, offering some drier days. Tourist activity remains low during this chilly month.
March
March marks the beginning of spring with slightly warmer temperatures reaching 51°F and nighttime lows of 39°F. Rainfall drops to 2.0 inches, making it one of the drier months. The weather begins to become more pleasant for outdoor activities.
April
April continues the spring warming trend with highs of 56°F and lows of 42°F, offering much more comfortable conditions. Rainfall remains low at 2.0 inches, matching March's dry conditions. This marks the start of more favorable weather for visitors.
May
May brings pleasant late spring weather with temperatures reaching 62°F and nighttime lows of 47°F. Rainfall hits its lowest point of the year at just 1.7 inches, creating excellent conditions for outdoor exploration. Tourist numbers begin to increase with the improving weather.
June
June offers warm and comfortable conditions with highs of 67°F and pleasant nighttime temperatures of 52°F. Rainfall increases slightly to 1.9 inches but remains quite manageable. This is an excellent month for all types of activities with ideal weather conditions.
July
July reaches the warmest temperatures of the year with highs of 71°F and comfortable lows of 56°F. Rainfall remains low at 1.8 inches, making it one of the driest summer months. This represents peak weather conditions with high tourist activity.
August
August maintains the peak summer temperatures with highs of 71°F and lows of 56°F, matching July's warmth. Rainfall increases to 2.3 inches, marking the beginning of the transition toward wetter months. Despite increased precipitation, conditions remain favorable for tourism.
September
September sees temperatures beginning to cool with highs of 66°F and lows of 52°F, still quite pleasant for most activities. Rainfall increases slightly to 2.4 inches as the wet season approaches. This shoulder season month offers good weather with fewer crowds.
October
October brings further cooling with temperatures reaching 60°F and nighttime lows of 48°F. Rainfall increases significantly to 3.4 inches, marking the start of the wetter season. The weather remains suitable for activities but rain gear becomes advisable.
November
November continues the cooling trend with highs of 53°F and lows of 42°F as autumn progresses. Rainfall reaches 3.6 inches, making it one of the wettest months of the year. Tourist numbers decline as weather becomes less favorable.
December
December brings winter conditions with temperatures dropping to 48°F highs and 37°F lows. Rainfall peaks at 3.6 inches, matching November as the wettest month. Cold temperatures and frequent precipitation make this the least favorable time for most outdoor activities.