South Bristol, ME climate
South Bristol has chilly, snowy winters and cool summers, with plenty of rain. A typical July afternoon reaches 75°, a January night drops to 15°, and about 79 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in South Bristol feels like
Winter
Spring
Summer
Fall
South Bristol weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 31° | 15° | 3.7" | 19.6" | 12 | 25 | 14° – 30° |
| February | 33° | 17° | 3.4" | 20.3" | 11 | 25 | 11° – 31° |
| March | 40° | 25° | 4.2" | 14.1" | 11 | 18 | 26° – 39° |
| April | 51° | 34° | 4.2" | 4.4" | 12 | 2 | 39° – 47° |
| May | 61° | 44° | 3.7" | 0 | 14 | 0 | 47° – 56° |
| June | 70° | 53° | 4.2" | 0 | 13 | 0 | 59° – 65° |
| July | 75° | 59° | 3.3" | 0 | 12 | 0 | 63° – 70° |
| August | 75° | 59° | 3.2" | 0 | 10 | 0 | 64° – 70° |
| September | 68° | 52° | 4.1" | 0 | 10 | 0 | 57° – 65° |
| October | 57° | 42° | 5.0" | 0.3" | 12 | 0 | 46° – 56° |
| November | 46° | 32° | 4.5" | 3.5" | 12 | 2 | 34° – 44° |
| December | 37° | 22° | 4.6" | 16.5" | 13 | 15 | 23° – 37° |
| Year | 54° | 38° | 48.0" | 78.7" | 142 | 88 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in South Bristol
South Bristol gets 48 inches of rain and melted snow a year. October is the wettest month and August the driest. Rain or snow falls on about 142 days a year. Snow covers the ground about 88 days of the year.
About 175 frost-free days a year
In half of years the last 32° night comes by April 28 and the first one by October 21. That leaves about 175 frost-free days for gardens, shorter than 54% of U.S. towns.
Heating and cooling a home in South Bristol
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In South Bristol, 96% of that work is heating and 4% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
South Bristol and its neighbors
South Bristol borders 4 towns with climate data. January nights across them vary by 3.0°. Newcastle has both the coldest January nights (12°) and the hottest July afternoons (78°). South Bristol’s January low is 15° and its July high 75°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How South Bristol compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in South Bristol averaged 1.7° warmer than the 1900s. The biggest change is in December (+3.6°). The shift is larger than in 84% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at South Bristol’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 11° to 31°. August is the most reliable, staying within 6°.
Common questions about South Bristol’s climate
What is the coldest month in South Bristol?
January, with a typical high of 31° and a low of 15°.
What is the hottest month in South Bristol?
July, with a typical high of 75° and a low of 59°.
How much snow does South Bristol get?
About 79 inches in a normal winter, most of it in February.
When is the first frost in South Bristol?
In half of years the first 32° night comes by October 21, and the last spring frost by April 28.
What is the rainiest month in South Bristol?
October, with 5.0 inches of rain and melted snow. The year totals 48 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for South Bristol itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Newcastle, ME (11 mi, snow) and Westport Island, ME (8 mi, frost, heat and degree days). Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.