Northwest Harwinton has chilly, snowy winters and pleasant summers, with plenty of rain
A typical July afternoon reaches 82°, a January night drops to 16°, and about 59 inches of snow falls in a normal winter.
A year in Northwest Harwinton at a glance
Each month’s typical high and low, and what it brings.
What stands out about Northwest Harwinton’s climate
Read from where Northwest Harwinton sits among Connecticut’s towns. The page puts what stands out first.
59 inches of snow, 53 of rain and melt
October is the wettest month and February the driest. Rain or snow falls on about 143 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Living with Northwest Harwinton’s climate
What the numbers mean for a garden, a driveway, a furnace and a free afternoon.
151 frost-free days. 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 5.
About 59" a winter over 15 days with an inch or more, most in February. Snow covers the ground about 80 days a year.
Months averaging under 55° run from October through April. Heating is 94% of the year’s heating-and-cooling load.
About 7 days a year reach 90°, and July afternoons average 82°.
The nicest months are May, June, July, August and September. 9.7 miles of trails are waiting.
Parks & trails →Normals are averages. Ice storms, nor’easters, floods and heat waves are on the natural hazards page.
Natural hazards →About 151 frost-free days a year
In half of years the last 32° night comes by May 8 and the first by October 5.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
What a year in Northwest Harwinton feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
Warmer than it used to be
The last 30 years in Northwest Harwinton averaged 1.8° warmer than the 1900s. The biggest change is in December (+3.2°).
A bigger shift than in 85% of U.S. towns.
Change by month
Northwest Harwinton and its neighbors
Torrington has the coldest January nights next door (15°) and New Hartford the hottest July afternoons (83°). 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 Northwest Harwinton compares
Against every U.S. town on TownTapestry, each counted once, with its place in Connecticut.
Northwest Harwinton 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 | 34° | 16° | 3.8" | 13.1" | 13 | 23 | 16° – 31° |
| February | 37° | 17° | 3.3" | 15.8" | 10 | 21 | 13° – 34° |
| March | 45° | 24° | 4.4" | 12.7" | 12 | 17 | 27° – 44° |
| April | 58° | 34° | 4.2" | 2.6" | 13 | 2 | 41° – 51° |
| May | 69° | 45° | 4.2" | 0 | 14 | 0 | 52° – 62° |
| June | 77° | 54° | 4.8" | 0 | 13 | 0 | 63° – 69° |
| July | 82° | 59° | 4.5" | 0 | 12 | 0 | 66° – 74° |
| August | 80° | 58° | 4.6" | 0 | 11 | 0 | 65° – 72° |
| September | 72° | 51° | 4.9" | 0 | 11 | 0 | 58° – 66° |
| October | 61° | 40° | 5.3" | 0.3" | 12 | 0 | 46° – 56° |
| November | 49° | 31° | 4.1" | 2.6" | 11 | 2 | 36° – 45° |
| December | 38° | 22° | 4.7" | 12.0" | 13 | 15 | 23° – 41° |
| Year | 58° | 37° | 52.7" | 59.1" | 143 | 80 |
Heating and cooling a home in Northwest Harwinton
94% 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 13° to 34°. June is the most reliable, staying within 6°.
Common questions about Northwest Harwinton’s climate
What is the coldest month in Northwest Harwinton?
January, with a typical high of 34° and a low of 16°.
What is the hottest month in Northwest Harwinton?
July, with a typical high of 82° and a low of 59°. About 7 days a year reach 90°.
How much snow does Northwest Harwinton get?
About 59 inches in a normal winter, most of it in February.
When is the first frost in Northwest Harwinton?
In half of years the first 32° night comes by October 5, and the last spring frost by May 8.
What is the rainiest month in Northwest Harwinton?
October, with 5.3 inches of rain and melted snow. The year totals 53 inches.
Neighbors talk weather
Gardens, snow, and the best days of the year in Northwest Harwinton.
Your answer becomes a post in Town Square.
Temperatures and rainfall come from NOAA’s gridded climate normals for Northwest Harwinton itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Bakersville, CT (6 mi) away. 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.