Portland, ME Weather
Portland hourly forecast: next 24 hours
Today's high of 66°F (19°C) is about 5°F (3°C) below the typical September high of 71°F (22°C).
Current conditions in detail
Portland weather tomorrow (Thursday, September 17)
Tomorrow in Portland looks overcast, with a high of 63° and an overnight low of 61°. There is a 86% chance of rain - plan accordingly. Winds top out near 11 mph, and the UV index reaches 6 (moderate).
Portland 14-day forecast
About the weather in Portland
Seasons are the whole story in Portland. The gap between an average July and an average January is 25°C - warm summers and cold, often snowy winters - which in practice means 78°F (26°C) afternoons at one end of the calendar and 33°F (1°C) at the other.
Portland weather: quick facts
- Hottest month: July - highs near 78°F (26°C)
- Coldest month: January - highs near 33°F (1°C)
- Decade extremes (2015-2024): 97°F (36°C) high · -19°F (-28°C) low
- Wettest month: December (11 rainy days) · Sunniest: July (11.3 h sun/day)
- Climate type: humid continental
- Annual swing: 25°C between the average warmest and coolest month · day to night: 8°C
- Snow: about 24 days a year
- Months with freezing average lows: 4
- Average humidity: 73%
Temperatures through the year
Between the average July and the average January lie 25°C, a wider spread than roughly 83% of the cities we track. Warmth peaks in July: highs of 78°F (26°C), lows of 64°F (18°C). January is the coolest month, with highs of 33°F (1°C) and lows near 19°F (-7°C). Sunshine averages 8.4 hours a day over the year, peaking in July at 11.3 hours.
Rain, sun and snow
Overnight lows average at or below freezing for 4 months, December through March. Snow falls on roughly 24 days a year, mostly November through April. Across the gridded 2015-2024 daily record, the highest daily maximum for this location was 97°F (36°C) and the lowest daily minimum -19°F (-28°C).
Season by season
Spring (March through May)
Spring stays firmly cold here - highs near 52°F (11°C), nights near 37°F (3°C), and rain falls on around 31 of the 90 days, plus about 6 snowy days.
Summer (June through August)
Through summer, Portland is mild and warm: 76°F (24°C) by day, 61°F (16°C) after dark, and rain falls on around 32 of the 90 days. Daylight is generous - around 11.1 hours of sun a day.
Fall (September through November)
Through fall, Portland is mild: 59°F (15°C) by day, 46°F (8°C) after dark, and expect showers on roughly 27 days across the season.
Winter (December through February)
Winter brings deep cold here - highs near 36°F (2°C), nights near 21°F (-6°C), and expect showers on roughly 30 days across the season, plus about 16 snowy days. Wind sharpens cold like this considerably; pair the forecast winds with the wind speed converter to judge exposed conditions.
Average temperatures in Portland by month
| 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% |