Union has cold, snowy winters and pleasant summers, with plenty of rain
A typical July afternoon reaches 81°, a January night drops to 12°, and about 62 inches of snow falls in a normal winter.
A year in Union at a glance
Each month’s typical high and low, and what it brings.
What stands out about Union’s climate
Read from where Union sits among New Hampshire’s towns. The page puts what stands out first.
Warmer than it used to be
The last 30 years in Union averaged 1.5° warmer than the 1900s. The biggest change is in December (+3.2°).
A bigger shift than in 69% of U.S. towns.
Change by month
What a year in Union feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
62 inches of snow, 48 of rain and melt
October is the wettest month and February the driest. Rain or snow falls on about 132 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
About 136 frost-free days a year
In half of years the last 32° night comes by May 16 and the first by September 30.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
Living with Union’s climate
What the numbers mean for a garden, a driveway, a furnace and a free afternoon.
136 frost-free days. The last frost comes by May 16 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.
About 62" a winter over 19 days with an inch or more, most in January. Snow covers the ground about 91 days a year.
Months averaging under 55° run from October through April. Heating is 95% of the year’s heating-and-cooling load.
About 10 days a year reach 90°, and July afternoons average 81°.
The nicest months are May, June, July, August and September.
Parks & trails →Normals are averages. Ice storms, nor’easters, floods and heat waves are on the natural hazards page.
Natural hazards →Union and its neighbors
Wakefield has the coldest January nights next door (11°) and Middleton the hottest July afternoons (81°). Tap a town to see its climate.
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.
How Union compares
Against every U.S. town on TownTapestry, each counted once, with its place in New Hampshire.
Union 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 | 30° | 12° | 3.4" | 18.8" | 12 | 27 | 12° – 29° |
| February | 34° | 13° | 3.2" | 16.9" | 9 | 25 | 9° – 30° |
| March | 42° | 21° | 4.0" | 9.4" | 11 | 19 | 24° – 40° |
| April | 56° | 32° | 4.2" | 1.6" | 11 | 2 | 39° – 48° |
| May | 67° | 43° | 3.7" | 0 | 12 | 0 | 50° – 60° |
| June | 76° | 52° | 4.4" | 0 | 13 | 0 | 61° – 68° |
| July | 81° | 58° | 4.1" | 0 | 11 | 0 | 65° – 72° |
| August | 79° | 56° | 3.8" | 0 | 10 | 0 | 65° – 70° |
| September | 71° | 48° | 3.9" | 0 | 10 | 0 | 56° – 63° |
| October | 59° | 38° | 5.0" | 0.3" | 11 | 0 | 45° – 55° |
| November | 47° | 28° | 4.1" | 2.1" | 11 | 2 | 32° – 43° |
| December | 36° | 19° | 4.4" | 12.8" | 12 | 15 | 21° – 35° |
| Year | 56° | 35° | 48.1" | 61.9" | 132 | 91 |
Heating and cooling a home in Union
95% of the work is heating, so the furnace matters far more than the air conditioner.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. Source: NOAA station normals.
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 9° to 30°. August is the most reliable, staying within 6°.
Common questions about Union’s climate
What is the coldest month in Union?
January, with a typical high of 30° and a low of 12°.
What is the hottest month in Union?
July, with a typical high of 81° and a low of 58°. About 10 days a year reach 90°.
How much snow does Union get?
About 62 inches in a normal winter, most of it in January.
When is the first frost in Union?
In half of years the first 32° night comes by September 30, and the last spring frost by May 16.
What is the rainiest month in Union?
October, with 5.0 inches of rain and melted snow. The year totals 48 inches.
Neighbors talk weather
Gardens, snow, and the best days of the year in Union.
Your answer becomes a post in Town Square.
Temperatures and rainfall come from NOAA’s gridded climate normals for Union itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Lakeport 2, NH (22 mi, snow) and Sanford 2 Nnw, ME (12 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. Today’s forecast: National Weather Service.