South Portland in Fall
In fall (September, October and November), South Portland sees average daytime highs around 56°F and overnight lows near 47°F, with 13.6 in of precipitation over about 30 wet days across the season. It is the 2nd-warmest season and the wettest season of the year.
Over the season highs ease from about 68°F in early September to 42°F by late November. The sky is clear or mostly clear about 37% of the time across fall, and the air most often feels dry.
Fall is South Portland's 2nd-best season to visit on our travel score. For the whole year in context, see South Portland's year-round climate.
- Avg daytime high
- 56°F
- 2nd-warmest season
- Avg overnight low
- 47°F
- Precipitation
- 13.6 in
- 30 wet days
- Avg wind
- 10 mph
- Travel score
- 3.8
- 2nd-best season
- Months
- Sep · Oct · Nov
Temperature in South Portland in Fall
Over the season highs ease from about 68°F in early September to 42°F by late November.
A typical fall day in South Portland reaches about 56°F and drops to 47°F overnight. The warmest of the three months is September, the coolest November.
How fall really feels in South Portland
Once humidity and wind are folded in, fall brings about 0 days that feel above 90°F and 21 that feel at or below 32°F.
The story in fall is cold — wind chill drags the overnight "feels like" below the raw low.
South Portland weather by month
How the three fall months (September, October and November) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 32° / 20° | 3.9 | 9.9 | 6.9 | 9.1 | 0.0 |
| Feb | 33° / 21° | 3.6 | 8.9 | 6.5 | 10.2 | 0.0 |
| Mar | 38° / 28° | 4.6 | 10.9 | 5.6 | 11.6 | 0.0 |
| Apr | 47° / 38° | 4.7 | 10.7 | 1.9 | 13.2 | 1.6 |
| May | 56° / 47° | 3.9 | 11 | 0.1 | 14.5 | 3.7 |
| Jun | 65° / 56° | 4.0 | 10.3 | 0 | 15.2 | 5.7 |
| Jul | 71° / 63° | 3.1 | 9.2 | 0 | 14.9 | 6.7 |
| Aug | 71° / 63° | 3.2 | 8.4 | 0 | 13.8 | 6.9 |
| Sep | 65° / 57° | 3.7 | 8.7 | 0 | 12.3 | 6.2 |
| Oct | 56° / 47° | 5.4 | 10.6 | 0.2 | 10.8 | 3.8 |
| Nov | 46° / 37° | 4.5 | 10.4 | 1.4 | 9.5 | 1.3 |
| Dec | 37° / 28° | 4.9 | 11 | 5.8 | 8.8 | 0.0 |
Cloud cover in Fall
The sky is clear or mostly clear about 37% of the time across fall.
Chance of precipitation in Fall
South Portland gets around 13.6 in of rain and snow over 30 wet days across fall. The line is the day-by-day chance of measurable precipitation.
Humidity in Fall
Most of fall feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Fall
Winds average 10 mph across fall.
Sunrise & sunset in Fall
Daylight runs from about 13 h 06 min in early September to 9 hours by late November. The lit band spans sunrise to sunset each day.
Solar energy in Fall
Average shortwave solar energy reaching the ground each day across fall, about 3.0 kWh/m².
Hazard calendar for South Portland
In fall, South Portland overlaps its atlantic hurricane season. The full year is below, with each hazard's peak months called out.
South Portland sits in the Atlantic hurricane belt; the season peaks August–October.
Is fall a good time to visit South Portland?
Our two travel scores rate fall for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
fall is a weaker month for outdoor sightseeing in South Portland.
What to pack for South Portland in Fall
From fall's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In fall, South Portland sees daytime highs around 56°F and nights near 47°F. Pack a warm layer. Worth having: a heavy coat and rain gear. About 30 days see rain.
Sea temperature near South Portland in Fall
The nearest coast averages about 54°F across fall — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea offshore is warmest in August at about 63°F and coldest in March near 38°F.
The water stays below 68°F all year — cool enough that most swimmers want a wetsuit.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°F) | 42 | 39 | 38 | 42 | 48 | 55 | 62 | 63 | 60 | 54 | 49 | 45 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Bracing | Bracing | Cool | Cool | Cool | Bracing | Bracing | Bracing |
| Sea temperature (°F) | Comfort | |
|---|---|---|
| Jan | 42 | Bracing |
| Feb | 39 | Bracing |
| Mar | 38 | Bracing |
| Apr | 42 | Bracing |
| May | 48 | Bracing |
| Jun | 55 | Bracing |
| Jul | 62 | Cool |
| Aug | 63 | Cool |
| Sep | 60 | Cool |
| Oct | 54 | Bracing |
| Nov | 49 | Bracing |
| Dec | 45 | Bracing |
UV index in South Portland in Fall
Clear-sky midday UV across fall averages around 3 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in South Portland peaks around July 12 at about 7 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 23 at about 1 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 1 | 2 | 4 | 5 | 7 | 7 | 7 | 4 | 6 | 3 | 2 | 1 |
| Level | Low | Moderate | Moderate | Moderate | High | High | Very high | Moderate | High | Moderate | Low | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 1 | Low |
| Feb | 2 | Moderate |
| Mar | 4 | Moderate |
| Apr | 5 | Moderate |
| May | 7 | High |
| Jun | 7 | High |
| Jul | 7 | Very high |
| Aug | 4 | Moderate |
| Sep | 6 | High |
| Oct | 3 | Moderate |
| Nov | 2 | Low |
| Dec | 1 | Low |
Where is South Portland?
South Portland sits at 43.6°N, 70.2°W, 23 ft above sea level, in United States. The nearest listed city is Portland, 1.2 mi away.
Topography around South Portland
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of South Portland.
Within 2 miles, the terrain around South Portland has only modest variations in elevation — a maximum elevation change of 207 ft around an average of 46 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 548 ft; within 50 miles, large variations in elevation — a maximum elevation change of 2,182 ft.
The land around South Portland is covered by water (36%), trees (32%) and artificial surfaces (22%) within 2 miles, water (48%) and trees (37%) within 10 miles, and trees (60%) and water (34%) within 50 miles.
United States travel facts
- Power plugs
- Type A / B
- 120 V · 60 Hz
- Prices
- ≈ 100% of US
- price level, 2025
- GDP per capita
- $90,027
- 2025
- Happiness
- 6.8 / 10
- World Happiness, 2025
- Safe drinking water
- 98%
- of population, 2024
- Homicide rate
- 5.8
- per 100k, 2023
- Road deaths
- 12.7
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for South Portland (43.6415°, -70.2409°, elevation 23 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.