Photo: John Phelan · CC BY-SA 4.0Midwinter lows in South Windham sink below those of 91% of U.S. towns
The warmest part of a July day comes in at 81° on average. Seasons differ by 69°, from the coldest nights to the warmest afternoons. By July afternoons alone, it runs cooler than 88% of U.S. towns. Garden planting can start around April 26; autumn frost returns near October 15.
A year in South Windham at a glance
Each month’s typical high and low, and what it brings.
What stands out about South Windham’s climate
Compared with towns across the U.S., with South Windham’s place in Maine beside it.
What a year in South Windham feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 170 frost-free days a year
In half of years the last 32° night comes by April 26 and the first by October 15. Frost and day counts come from NOAA’s station at Portland International Jetport, ME, 9 miles from the town’s center, at about the same height.
The 2023 USDA map puts South Windham’s center in zone 5b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −13°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 69 inches of snow a winter
Snow, measured at Portland International Jetport, ME, falls mostly in January. Precipitation (rain plus melted snow) adds up to 49 inches a year; October is the wettest month and January the driest. Rain or snow falls on about 131 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in South Windham
94% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through May.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Portland International Jetport, ME.
Living with South Windham’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
170 frost-free days in zone 5b. The last frost comes by Apr 26 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Oct 15.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September.
Parks & trails →Of the yearly building losses FEMA expects in South Windham from natural hazards, river flooding is the largest share (48%); heat waves, cold waves, winter storms and ice storms together are 16%. Normals are averages; the hazards page covers the extremes.
Natural hazards →South Windham and its neighbors
Every town next door is within a degree of South Windham in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like South Windham’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| South Windham, ME | 12° | 81° | 49" | 69" |
| Walton, NY | 13° | 80° | 47" | 71" |
| Dalton, MA | 13° | 80° | 48" | 77" |
| Torrington, CT | 15° | 81° | 51" | 59" |
| Bennington, VT | 13° | 81° | 44" | 75" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in South Windham averaged 1.8° warmer than the 1900s. The biggest change is in December (+3.5°).
A bigger shift than in 80% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How South Windham compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with South Windham’s place among Maine’s.
South Windham weather by month
Highs, lows and precipitation from NOAA’s grid at South Windham’s center; snow, wet days and snow on the ground from Portland International Jetport, ME. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 31° | 12° | 3.4" | 18.6" | 11 | 23 | 12° – 29° |
| February | 34° | 14° | 3.4" | 16.6" | 10 | 21 | 11° – 31° |
| March | 42° | 23° | 4.1" | 13.6" | 11 | 16 | 25° – 40° |
| April | 55° | 33° | 4.4" | 2.8" | 11 | 2 | 41° – 49° |
| May | 66° | 43° | 3.8" | 0.0" | 13 | 0 | 50° – 60° |
| June | 75° | 53° | 4.4" | 0.0" | 12 | 0 | 61° – 67° |
| July | 81° | 59° | 3.7" | 0.0" | 11 | 0 | 65° – 73° |
| August | 79° | 58° | 3.6" | 0.0" | 9 | 0 | 66° – 71° |
| September | 71° | 49° | 3.9" | 0.0" | 9 | 0 | 56° – 65° |
| October | 59° | 39° | 5.2" | 0.2" | 11 | 0 | 45° – 56° |
| November | 47° | 29° | 4.4" | 2.3" | 11 | 2 | 33° – 43° |
| December | 36° | 19° | 4.5" | 14.6" | 12 | 11 | 21° – 36° |
| Year | 57° | 36° | 49.0" | 68.7" | 131 | 74 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 11° to 31°. August is the most reliable, staying within 5°.
Where South Windham’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at South Windham’s center.
- Snow: Portland International Jetport, ME.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Portland International Jetport, ME, 9 miles from the town’s center, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about South Windham’s climate
What is the weather like in South Windham?
A typical July afternoon reaches 81°, a January night drops to 12°, and about 69 inches of snow falls in a normal winter. Colder January nights than 91% of U.S. towns; cooler July afternoons than 88% of U.S. towns.
How cold does it get in South Windham in winter?
January nights average 12°. About 144 nights a year reach 32° or below and 7 reach 0° or below. In the coldest January of the last 30 years the month averaged 12°.
How much snow does South Windham get?
About 69 inches in a normal winter at Portland International Jetport, ME, most of it in January, with snow on the ground about 74 days a year.
How hot does it get in South Windham?
July, with a typical high of 81° and a low of 59°. About 5 days a year reach 90° (Portland International Jetport, ME).
When is the first and last frost in South Windham?
In half of years the last spring frost (32°) comes by April 26 and the first fall frost by October 15, about 170 frost-free days, at Portland International Jetport, ME.
What growing zone is South Windham in?
Zone 5b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −13°.
What is the best time of year to visit South Windham?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is South Windham getting warmer?
Yes: 1991–2020 averaged 1.8° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 80% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in South Windham.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.