Photo: Ascended Dreamer · CC BY 4.0Northumberland sits near the bottom of U.S. towns for winter warmth
In July the day’s top temperature is typically 79°. Summers stay cool: July afternoons here are cooler than in 94% of U.S. towns. Warming shows here too: 1.7° more than in 1901–2000, led by December. The frost-free window for a garden runs roughly May 18 to September 30.
A year in Northumberland at a glance
Each month’s typical high and low, and what it brings.
What stands out about Northumberland’s climate
Compared with towns across the U.S., with Northumberland’s place in New Hampshire beside it.
What a year in Northumberland feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 132 frost-free days a year
In half of years the last 32° night comes by May 18 and the first by September 30. Frost and day counts come from NOAA’s station at Lancaster, NH, 6 miles from the town’s center, 220 ft lower.
The 2023 USDA map puts Northumberland’s center in zone 4b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −23°. 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 76 inches of snow a winter
Snow, measured at Lancaster, NH, falls mostly in January, February and December. Precipitation (rain plus melted snow) adds up to 41 inches a year; June is the wettest month and February the driest. Rain or snow falls on about 159 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Northumberland
97% 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 Lancaster, NH.
Living with Northumberland’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
132 frost-free days in zone 4b. The last frost comes by May 18 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Sep 30.
Months with highs of 62–84° and lows of 40° or more: June, July, August and September. 12 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Northumberland from natural hazards, avalanches are the largest share (64%); heat waves, cold waves, winter storms and ice storms together are 8%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Northumberland and its neighbors
Every town next door is within a degree of Northumberland in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Northumberland’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 |
|---|---|---|---|---|
| Northumberland, NH | 4° | 79° | 41" | 76" |
| Canton, NY | 8° | 80° | 39" | 77" |
| Houlton, ME | 4° | 78° | 42" | 96" |
| Rhinelander, WI | 3° | 78° | 33" | 82" |
| Stewartville, MN | 6° | 81° | 36" | 53" |
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 Northumberland averaged 1.7° warmer than the 1900s. The biggest change is in December (+4.0°).
A bigger shift than in 69% 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 Northumberland compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Northumberland’s place among New Hampshire’s.
Northumberland weather by month
Highs, lows and precipitation from NOAA’s grid at Northumberland’s center; snow, wet days and snow on the ground from Lancaster, NH. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 26° | 4° | 2.7" | 17.9" | 14 | 29 | 4° – 24° |
| February | 30° | 6° | 2.2" | 17.8" | 11 | 28 | 4° – 25° |
| March | 39° | 16° | 2.5" | 11.6" | 12 | 25 | 16° – 36° |
| April | 53° | 28° | 3.2" | 4.0" | 13 | 6 | 36° – 46° |
| May | 66° | 39° | 3.8" | 0.1" | 14 | 0 | 47° – 58° |
| June | 75° | 49° | 4.3" | 0.0" | 15 | 0 | 59° – 66° |
| July | 79° | 54° | 4.3" | 0.0" | 13 | 0 | 62° – 70° |
| August | 78° | 52° | 4.0" | 0.0" | 13 | 0 | 62° – 68° |
| September | 70° | 44° | 3.4" | 0.0" | 11 | 0 | 52° – 62° |
| October | 56° | 34° | 4.3" | 0.6" | 14 | 0 | 41° – 52° |
| November | 43° | 25° | 3.0" | 4.6" | 14 | 5 | 29° – 39° |
| December | 32° | 13° | 3.2" | 19.5" | 16 | 22 | 16° – 33° |
| Year | 54° | 30° | 40.9" | 76.1" | 159 | 114 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 4° to 25°. August is the most reliable, staying within 6°.
Where Northumberland’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 Northumberland’s center.
- Snow: Lancaster, NH.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Lancaster, NH, 6 miles from the town’s center, 220 ft lower; 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 Northumberland’s climate
What is the weather like in Northumberland?
A typical July afternoon reaches 79°, a January night drops to 4°, and about 76 inches of snow falls in a normal winter. Colder January nights than all but 167 U.S. towns; cooler July afternoons than 94% of U.S. towns.
How cold does it get in Northumberland in winter?
January nights average 4°. About 188 nights a year reach 32° or below and 38 reach 0° or below. In the coldest January of the last 30 years the month averaged 4°.
How much snow does Northumberland get?
About 76 inches in a normal winter at Lancaster, NH, most of it in January, February and December, with snow on the ground about 114 days a year.
How hot does it get in Northumberland?
July, with a typical high of 79° and a low of 54°. About 3 days a year reach 90° (Lancaster, NH).
When is the first and last frost in Northumberland?
In half of years the last spring frost (32°) comes by May 18 and the first fall frost by September 30, about 132 frost-free days, at Lancaster, NH.
What growing zone is Northumberland in?
Zone 4b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −23°.
What is the best time of year to visit Northumberland?
By one simple rule (highs of 62–84° and lows of 40° or more), June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Northumberland getting warmer?
Yes: 1991–2020 averaged 1.7° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 69% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Northumberland.
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.