Portland, ME Climate & Monthly Averages
The climate of Portland
Located in Maine, United States, Portland experiences a humid continental climate with warm summers and cold, often snowy winters. Afternoon temperatures peak near 78°F (26°C) in July and dip to about 33°F (1°C) in January, with around 46.3 inches (1175 mm) of precipitation falling across the year.
Climate quick facts
- Hottest month: July - highs near 78°F (26°C)
- Coldest month: January - highs near 33°F (1°C)
- Record high: 97°F (36°C) · Record low: -19°F (-28°C) (2015–2024)
- Wettest month: December (11 rainy days) · Sunniest: July (11.3 h sun/day)
- Climate type: humid continental - warm summers and cold, often snowy winters
- Snow: about 24 days a year
Temperatures through the year
The warmest stretch of the year centers on July. Highs average 78°F (26°C) and overnight lows stay near 64°F (18°C). The coolest month is January, with typical highs of 33°F (1°C) and lows around 19°F (-7°C). Based on 2015–2024 weather data, temperatures have reached as high as 97°F (36°C) and dropped as low as -19°F (-28°C).
Rain, sun and snow
December is usually the wettest month. It brings about 5.0 inches (128 mm) of rain over 11 days, while May is the driest. July brings the most sunshine, averaging 11.3 hours of sun a day. Snow falls on about 24 days in a typical year, mostly from November through April.
Monthly climate table
| Month | High | Low | Rain days | Precipitation | Sunshine | Humidity |
|---|---|---|---|---|---|---|
| January | 33° | 19° | 10 | 4.1 in | 5.9 h/day | 68% |
| February | 35° | 18° | 9 | 3.2 in | 6.9 h/day | 69% |
| March | 42° | 26° | 11 | 3.8 in | 8.0 h/day | 67% |
| April | 51° | 36° | 11 | 4.5 in | 8.2 h/day | 70% |
| May | 63° | 47° | 9 | 2.7 in | 10.1 h/day | 72% |
| June | 72° | 57° | 11 | 3.8 in | 11.1 h/day | 76% |
| July | 78° | 64° | 10 | 3.8 in | 11.3 h/day | 77% |
| August | 77° | 63° | 11 | 3.6 in | 10.8 h/day | 78% |
| September | 71° | 57° | 8 | 3.4 in | 9.4 h/day | 78% |
| October | 60° | 47° | 9 | 4.5 in | 7.1 h/day | 77% |
| November | 47° | 35° | 9 | 3.8 in | 6.5 h/day | 71% |
| December | 38° | 26° | 11 | 5.0 in | 5.7 h/day | 72% |
Portland month by month
Portland weather in January
January brings highs around 33°F (1°C), lows near 19°F (-7°C), about 10 wet days and roughly 6 snowy days - typically the coldest month of the year in Portland.
Portland weather in February
February brings highs around 35°F (2°C), lows near 18°F (-8°C), about 9 wet days and roughly 6 snowy days.
Portland weather in March
March brings highs around 42°F (5°C), lows near 26°F (-3°C), about 11 wet days and roughly 4 snowy days.
Portland weather in April
April brings highs around 51°F (11°C), lows near 36°F (2°C), about 11 wet days and roughly 2 snowy days.
Portland weather in May
May brings highs around 63°F (17°C), lows near 47°F (8°C), about 9 wet days - typically the driest month of the year in Portland.
Portland weather in June
June brings highs around 72°F (22°C), lows near 57°F (14°C), about 11 wet days.
Portland weather in July
July brings highs around 78°F (26°C), lows near 64°F (18°C), about 10 wet days - typically the hottest month and the sunniest month of the year in Portland.
Portland weather in August
August brings highs around 77°F (25°C), lows near 63°F (17°C), about 11 wet days.
Portland weather in September
September brings highs around 71°F (22°C), lows near 57°F (14°C), about 8 wet days.
Portland weather in October
October brings highs around 60°F (15°C), lows near 47°F (8°C), about 9 wet days.
Portland weather in November
November brings highs around 47°F (9°C), lows near 35°F (2°C), about 9 wet days and roughly 1 snowy days.
Portland weather in December
December brings highs around 38°F (3°C), lows near 26°F (-4°C), about 11 wet days and roughly 4 snowy days - typically the wettest month of the year in Portland.
Seasons in Portland
Spring (March through May)
Spring in Portland is brisk and cold, with daytime highs averaging 52°F (11°C) and nights around 37°F (3°C); expect showers on roughly 31 days across the season, plus around 6 snowy days.
Summer (June through August)
Summer in Portland brings comfortable warmth, with daytime highs averaging 76°F (24°C) and nights around 61°F (16°C); expect showers on roughly 32 days across the season.
Fall (September through November)
Fall in Portland is mild, with daytime highs averaging 59°F (15°C) and nights around 46°F (8°C); expect showers on roughly 27 days across the season.
Winter (December through February)
Winter in Portland brings deep cold, with daytime highs averaging 36°F (2°C) and nights around 21°F (-6°C); expect showers on roughly 30 days across the season, plus around 16 snowy days. Wind makes those temperatures feel harsher than they sound - pair the forecast winds with the wind speed converter to judge conditions on exposed skin.
Climate questions, answered
What is the average temperature in Portland?
Is Portland hot in summer?
Is Portland cold in winter?
How many rainy days does Portland get in a year?
Best time to visit Portland
The best time to visit Portland is generally May to October, when this window offers the warmest, brightest days of the year. Daytime temperatures in that window typically sit near 70°F (21°C).
Pack for Portland with a heavy insulated coat, hat and gloves for winter; a compact umbrella or rain shell - showers are a regular feature. Evenings can feel noticeably cooler than afternoons - July nights average 64°F (18°C).
Portland temperature records (2015-2024)
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.