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Hourly Forecast
Daylight Hours
06:28
Sunrise
18:42
Sunset
Moon
Waxing Crescent
12:32
Moonrise
20:35
Moonset
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Weather in South Portland today, September 16, 2026
Expect reduced visibility in South Portland on September 16, 2026 where fog patches form. Allow more time for morning journeys if the air stays thick. Expect a grey start, with morning cloud around 100% by 08:00. Outdoor plans early on should not rely on bright skies.
The temperature range runs from about 11°C up to 21°C. The air stays humid, with relative humidity between 58% and 97% and the peak around 06:00. Winds stay light, near 6.5 km/h by 16:00, so the day feels still more than breezy.
Through the afternoon cloud remains the main feature, with cover near 100% around 21:00. Bright spells should stay limited even as the day wears on. Horizontal visibility sits around 15.5 km, briefly nearer 12.6 km. Daylight runs from 06:28 to 18:42, lasting 12 hours 13 minutes of sunlight today.
The practical takeaway for South Portland on September 16, 2026 is reduced clarity at times, so plan journeys with care near 21°C.
Frequently asked questions about weather in South Portland
How warm does it get in South Portland?
The warmest month in South Portland is July, with average high temperatures of 23°C. The average temperature during this period is around 20°C.
How cold does it get in South Portland?
The coldest month in South Portland is January, with average low temperatures of -5°C. The average temperature during this period is around -2°C.
What is the wettest time of year in South Portland?
The wettest month in South Portland is December, with an average of 147mm of precipitation.
What is the driest time of year in South Portland?
The driest month in South Portland is September, with an average of 76mm of precipitation.
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