Williamstown, MA climate
Williamstown has cold winters and pleasant summers. A typical July afternoon reaches 81°, a January night drops to 14°.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Williamstown feels like
Winter
Spring
Summer
Fall
Williamstown weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 32° | 14° | 2.9" | 12° – 31° |
| February | 34° | 15° | 2.4" | 10° – 31° |
| March | 43° | 23° | 3.1" | 26° – 43° |
| April | 57° | 33° | 3.3" | 39° – 50° |
| May | 69° | 44° | 3.7" | 51° – 62° |
| June | 77° | 53° | 4.5" | 62° – 69° |
| July | 81° | 58° | 4.4" | 65° – 74° |
| August | 79° | 56° | 4.2" | 65° – 72° |
| September | 72° | 48° | 4.4" | 56° – 64° |
| October | 60° | 38° | 4.2" | 44° – 55° |
| November | 48° | 29° | 3.3" | 34° – 44° |
| December | 37° | 21° | 3.4" | 21° – 40° |
| Year | 57° | 36° | 43.6" |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Williamstown
Williamstown gets 44 inches of rain and melted snow a year. June is the wettest month and February the driest.
About 147 frost-free days a year
In half of years the last 32° night comes by May 10 and the first one by October 4. That leaves about 147 frost-free days for gardens, shorter than 83% of U.S. towns.
Heating and cooling a home in Williamstown
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Williamstown, 95% of that work is heating and 5% is cooling, so the furnace matters far more than the air conditioner.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Williamstown and its neighbors
Williamstown borders 3 towns with climate data. January nights across them vary by 0.6°. Clarksburg has the coldest January nights (13°) and North Adams the hottest July afternoons (81°). Williamstown’s January low is 14° and its July high 81°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Williamstown compares
Compared with every U.S. town and city on TownTapestry, each counted once.
Warmer than it used to be
The last 30 years in Williamstown averaged 1.7° warmer than the 1900s. The biggest change is in December (+3.3°). The shift is larger than in 80% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Williamstown’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 10° to 31°. August is the most reliable, staying within 7°.
Common questions about Williamstown’s climate
What is the coldest month in Williamstown?
January, with a typical high of 32° and a low of 14°.
What is the hottest month in Williamstown?
July, with a typical high of 81° and a low of 58°. About 4 days a year reach 90°.
When is the first frost in Williamstown?
In half of years the first 32° night comes by October 4, and the last spring frost by May 10.
What is the rainiest month in Williamstown?
June, with 4.5 inches of rain and melted snow. The year totals 44 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Williamstown itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at North Adams Harriman Airport, MA (3 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.