Photo: Quintin Soloviev · CC BY 4.0Brunswick has some of the coolest summers among U.S. towns
Nights in January average 14°. In January, nights here are colder than in 88% of U.S. towns. Since 1901–2000, the year has warmed by 1.9°, most of all in December. Central heating does most of its work from October to April, in months below 50° on average.
A year in Brunswick at a glance
Each month’s typical high and low, and what it brings.
What stands out about Brunswick’s climate
Compared with towns across the U.S., with Brunswick’s place in Maine beside it.
What a year in Brunswick feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 160 frost-free days a year
In half of years the last 32° night comes by May 2 and the first by October 10. Frost and day counts come from NOAA’s station at Brunswick Nas, ME, 2.0 miles from the town’s center, at about the same height.
The 2023 USDA map puts Brunswick’s center in zone 5b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −11°. 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 67 inches of snow a winter
Snow, measured at Brunswick Nas, ME, falls mostly in January and March. Precipitation (rain plus melted snow) adds up to 48 inches a year; October is the wettest month and February the driest. Rain or snow falls on about 128 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Brunswick
95% 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 Brunswick Nas, ME.
Living with Brunswick’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
160 frost-free days in zone 5b. The last frost comes by May 2 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 10.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 77 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Brunswick from natural hazards, river flooding is the largest share (41%); heat waves, cold waves, winter storms and ice storms together are 19%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Brunswick and its neighbors
Durham has the coldest January nights next door (12°, 2° colder) and Durham the hottest July afternoons (80°, 2° warmer). Differences under a degree are within what the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Brunswick’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 |
|---|---|---|---|---|
| Brunswick, ME | 14° | 78° | 48" | 67" |
| Delhi, NY | 13° | 79° | 46" | 71" |
| Dalton, MA | 13° | 80° | 48" | 77" |
| Treasure Lake, PA | 17° | 80° | 45" | 53" |
| Brattleboro, VT | 13° | 81° | 51" | 60" |
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 Brunswick averaged 1.9° warmer than the 1900s. The biggest change is in December (+3.7°).
A bigger shift than in 83% 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 Brunswick compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Brunswick’s place among Maine’s.
Brunswick weather by month
Highs, lows and precipitation from NOAA’s grid at Brunswick’s center; snow, wet days and snow on the ground from Brunswick Nas, ME. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 31° | 14° | 3.5" | 19.3" | 11 | 19 | 13° – 30° |
| February | 33° | 16° | 3.3" | 13.6" | 10 | 19 | 11° – 31° |
| March | 41° | 24° | 4.1" | 18.7" | 12 | 15 | 25° – 40° |
| April | 52° | 34° | 4.3" | 3.3" | 10 | 2 | 40° – 48° |
| May | 63° | 44° | 3.7" | 0.0" | 13 | 0 | 48° – 58° |
| June | 72° | 54° | 4.4" | 0.0" | 11 | 0 | 60° – 66° |
| July | 78° | 60° | 3.5" | 0.0" | 11 | 0 | 64° – 72° |
| August | 77° | 59° | 3.4" | 0.0" | 8 | 0 | 65° – 71° |
| September | 70° | 52° | 4.0" | 0.0" | 9 | 0 | 57° – 65° |
| October | 58° | 41° | 5.2" | 0.2" | 11 | 0 | 45° – 56° |
| November | 47° | 31° | 4.5" | 1.9" | 12 | 2 | 33° – 43° |
| December | 37° | 21° | 4.4" | 9.8" | 11 | 9 | 22° – 37° |
| Year | 55° | 37° | 48.4" | 66.8" | 128 | 65 |
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 Brunswick’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 Brunswick’s center.
- Snow: Brunswick Nas, ME.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Brunswick Nas, ME, 2.0 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 Brunswick’s climate
What is the weather like in Brunswick?
A typical July afternoon reaches 78°, a January night drops to 14°, and about 67 inches of snow falls in a normal winter. Colder January nights than 88% of U.S. towns; cooler July afternoons than 96% of U.S. towns.
How cold does it get in Brunswick in winter?
January nights average 14°. About 151 nights a year reach 32° or below and 12 reach 0° or below. In the coldest January of the last 30 years the month averaged 13°.
How much snow does Brunswick get?
About 67 inches in a normal winter at Brunswick Nas, ME, most of it in January and March, with snow on the ground about 65 days a year.
How hot does it get in Brunswick?
July, with a typical high of 78° and a low of 60°. About 4 days a year reach 90° (Brunswick Nas, ME).
When is the first and last frost in Brunswick?
In half of years the last spring frost (32°) comes by May 2 and the first fall frost by October 10, about 160 frost-free days, at Brunswick Nas, ME.
What growing zone is Brunswick in?
Zone 5b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −11°.
What is the best time of year to visit Brunswick?
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 Brunswick getting warmer?
Yes: 1991–2020 averaged 1.9° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 83% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Brunswick.
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.