Photo: Ascended Dreamer · CC BY 4.0Jefferson gets about 95 inches of snow a winter, more than 97% of U.S. towns
A typical July afternoon reaches 78°, a January night drops to 5°, and about 95 inches of snow falls in a normal winter.
A year in Jefferson at a glance
Each month’s typical high and low, and what it brings.
What stands out about Jefferson’s climate
Compared with towns across the U.S., with Jefferson’s place in New Hampshire beside it.
What a year in Jefferson feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 146 frost-free days a year
In half of years the last 32° night comes by May 8 and the first by October 1. Frost and day counts come from NOAA’s station at Jefferson, NH, 2.6 miles from the town’s center, at about the same height.
The 2023 USDA map puts Jefferson’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 95 inches of snow a winter
Snow, measured at Jefferson, NH, falls mostly in January, February and December. Precipitation (rain plus melted snow) adds up to 43 inches a year; June is the wettest month and February the driest. Rain or snow falls on about 168 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Jefferson
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 Jefferson, NH.
Living with Jefferson’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
146 frost-free days in zone 4b. The last frost comes by May 8 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 1.
Months with highs of 62–84° and lows of 40° or more: June, July, August and September. 32 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Jefferson from natural hazards, avalanches are the largest share (65%); heat waves, cold waves, winter storms and ice storms together are 6%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Jefferson and its neighbors
Lancaster 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 Jefferson’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 |
|---|---|---|---|---|
| Jefferson, NH | 5° | 78° | 43" | 95" |
| Houlton, ME | 4° | 78° | 42" | 96" |
| Gouverneur, NY | 8° | 80° | 40" | 92" |
| Minocqua, WI | 3° | 77° | 33" | 99" |
| Sault Ste. Marie, MI | 8° | 76° | 37" | 120" |
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 Jefferson averaged 1.7° warmer than the 1900s. The biggest change is in December (+4.0°).
A bigger shift than in 73% 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 Jefferson compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Jefferson’s place among New Hampshire’s.
Jefferson weather by month
Highs, lows and precipitation from NOAA’s grid at Jefferson’s center; snow, wet days and snow on the ground from Jefferson, NH. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 27° | 5° | 2.8" | 20.1" | 16 | 29 | 5° – 24° |
| February | 30° | 7° | 2.4" | 19.8" | 14 | 27 | 5° – 26° |
| March | 39° | 16° | 2.8" | 16.7" | 14 | 26 | 18° – 36° |
| April | 52° | 28° | 3.5" | 6.5" | 14 | 8 | 35° – 45° |
| May | 66° | 39° | 3.9" | 0.5" | 15 | 0 | 46° – 57° |
| June | 74° | 48° | 4.6" | 0.0" | 15 | 0 | 58° – 65° |
| July | 78° | 53° | 4.5" | 0.0" | 13 | 0 | 61° – 69° |
| August | 77° | 51° | 4.2" | 0.0" | 12 | 0 | 61° – 67° |
| September | 69° | 44° | 3.5" | 0.0" | 11 | 0 | 52° – 61° |
| October | 56° | 34° | 4.5" | 1.8" | 14 | 1 | 40° – 52° |
| November | 43° | 25° | 3.2" | 7.7" | 15 | 8 | 29° – 39° |
| December | 32° | 14° | 3.4" | 21.7" | 17 | 22 | 16° – 33° |
| Year | 54° | 30° | 43.1" | 94.8" | 168 | 123 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 5° to 26°. August is the most reliable, staying within 6°.
Where Jefferson’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 Jefferson’s center.
- Snow: Jefferson, NH.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Jefferson, NH, 2.6 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 Jefferson’s climate
What is the weather like in Jefferson?
A typical July afternoon reaches 78°, a January night drops to 5°, and about 95 inches of snow falls in a normal winter. Colder January nights than 98% of U.S. towns; cooler July afternoons than 96% of U.S. towns.
How cold does it get in Jefferson in winter?
January nights average 5°. About 173 nights a year reach 32° or below and 24 reach 0° or below. In the coldest January of the last 30 years the month averaged 5°.
How much snow does Jefferson get?
About 95 inches in a normal winter at Jefferson, NH, most of it in January, February and December, with snow on the ground about 123 days a year.
How hot does it get in Jefferson?
July, with a typical high of 78° and a low of 53°. About 2 days a year reach 90° (Jefferson, NH).
When is the first and last frost in Jefferson?
In half of years the last spring frost (32°) comes by May 8 and the first fall frost by October 1, about 146 frost-free days, at Jefferson, NH.
What growing zone is Jefferson 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 Jefferson?
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 Jefferson getting warmer?
Yes: 1991–2020 averaged 1.7° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 73% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Jefferson.
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.