Photo: John Phelan · CC BY-SA 3.0Nights turn raw in Brentwood each January, colder than in 84% of U.S. towns
Midsummer highs settle at about 83°. From frosty January to warm July, readings climb 68°. By July afternoons alone, it runs cooler than 75% of U.S. towns. Central heating does most of its work from November to April, in months below 50° on average.
A year in Brentwood at a glance
Each month’s typical high and low, and what it brings.
What stands out about Brentwood’s climate
Compared with towns across the U.S., with Brentwood’s place in New Hampshire beside it.
What a year in Brentwood feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 148 frost-free days a year
In half of years the last 32° night comes by May 7 and the first by October 4. Frost and day counts come from NOAA’s station at Epping, NH, 4 miles from the town’s center, at about the same height.
The 2023 USDA map puts Brentwood’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −7°. 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 57 inches of snow a winter
Snow, measured at Epping, NH, is heaviest from January through February, about 15 inches a month. Precipitation (rain plus melted snow) adds up to 47 inches a year; October is the wettest month and February the driest. Rain or snow falls on about 120 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Brentwood
93% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Epping, NH.
Living with Brentwood’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
148 frost-free days in zone 6a. The last frost comes by May 7 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 4.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September. 14 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Brentwood from natural hazards, river flooding is the largest share (72%); heat waves, cold waves, winter storms and ice storms together are 6%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Brentwood and its neighbors
Every town next door is within a degree of Brentwood in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Brentwood’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 |
|---|---|---|---|---|
| Brentwood, NH | 15° | 83° | 47" | 57" |
| Pawling, NY | 17° | 83° | 47" | 58" |
| Oil City, PA | 18° | 83° | 45" | 54" |
| New Fairfield, CT | 17° | 83° | 50" | 49" |
| Ontario, OH | 17° | 82° | 42" | 49" |
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 Brentwood averaged 1.7° warmer than the 1900s. The biggest change is in December (+3.4°).
A bigger shift than in 75% 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 Brentwood compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Brentwood’s place among New Hampshire’s.
Brentwood weather by month
Highs, lows and precipitation from NOAA’s grid at Brentwood’s center; snow, wet days and snow on the ground from Epping, NH. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 34° | 15° | 3.2" | 15.2" | 10 | 23 | 16° – 31° |
| February | 37° | 17° | 3.2" | 13.9" | 8 | 21 | 13° – 32° |
| March | 45° | 25° | 4.3" | 9.9" | 10 | 15 | 28° – 44° |
| April | 57° | 35° | 4.1" | 2.8" | 11 | 2 | 42° – 50° |
| May | 68° | 45° | 3.8" | 0.0" | 11 | 0 | 51° – 62° |
| June | 77° | 54° | 4.1" | 0.0" | 12 | 0 | 62° – 69° |
| July | 83° | 60° | 3.7" | 0.0" | 10 | 0 | 67° – 74° |
| August | 81° | 59° | 3.6" | 0.0" | 9 | 0 | 67° – 73° |
| September | 73° | 51° | 3.8" | 0.0" | 9 | 0 | 59° – 66° |
| October | 61° | 39° | 4.8" | 0.1" | 10 | 0 | 47° – 57° |
| November | 49° | 30° | 3.9" | 1.6" | 10 | 2 | 35° – 45° |
| December | 39° | 22° | 4.4" | 13.1" | 11 | 13 | 25° – 39° |
| Year | 59° | 38° | 46.9" | 56.6" | 120 | 75 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 13° to 32°. August is the most reliable, staying within 6°.
Where Brentwood’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 Brentwood’s center.
- Snow: Epping, NH.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Epping, NH, 4 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 Brentwood’s climate
What is the weather like in Brentwood?
A typical July afternoon reaches 83°, a January night drops to 15°, and about 57 inches of snow falls in a normal winter. Colder January nights than 84% of U.S. towns; cooler July afternoons than 75% of U.S. towns.
How cold does it get in Brentwood in winter?
January nights average 15°. About 154 nights a year reach 32° or below and 9 reach 0° or below. In the coldest January of the last 30 years the month averaged 16°.
How much snow does Brentwood get?
About 57 inches in a normal winter at Epping, NH, heaviest from January through February, about 15 inches a month, with snow on the ground about 75 days a year.
How hot does it get in Brentwood?
July, with a typical high of 83° and a low of 60°. About 11 days a year reach 90° (Epping, NH).
When is the first and last frost in Brentwood?
In half of years the last spring frost (32°) comes by May 7 and the first fall frost by October 4, about 148 frost-free days, at Epping, NH.
What growing zone is Brentwood in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −7°.
What is the best time of year to visit Brentwood?
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 Brentwood getting warmer?
Yes: 1991–2020 averaged 1.7° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 75% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Brentwood.
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.