Cromwell, CT climate
Cromwell has chilly, snowy winters and warm summers. A typical July afternoon reaches 85°, a January night drops to 20°, and about 52 inches of snow falls in a normal winter.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Cromwell feels like
Winter
Spring
Summer
Fall
Cromwell 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 | 30-yr range |
|---|---|---|---|---|---|---|
| January | 37° | 20° | 3.4" | 14.2" | 11 | 20° – 35° |
| February | 40° | 21° | 2.9" | 14.8" | 11 | 16° – 37° |
| March | 48° | 28° | 4.0" | 9.4" | 11 | 32° – 47° |
| April | 60° | 37° | 4.0" | 1.1" | 12 | 45° – 54° |
| May | 71° | 48° | 3.5" | 0 | 12 | 54° – 64° |
| June | 80° | 57° | 4.2" | 0 | 12 | 65° – 71° |
| July | 85° | 63° | 3.8" | 0 | 11 | 69° – 78° |
| August | 83° | 62° | 3.9" | 0 | 10 | 69° – 76° |
| September | 76° | 54° | 4.1" | 0 | 9 | 62° – 69° |
| October | 64° | 42° | 4.5" | 0.7" | 11 | 49° – 60° |
| November | 52° | 33° | 3.7" | 1.4" | 10 | 38° – 47° |
| December | 42° | 25° | 4.2" | 10.1" | 12 | 27° – 44° |
| Year | 61° | 41° | 46.2" | 51.7" | 130 |
“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 Cromwell
Cromwell gets 46 inches of rain and melted snow a year. October is the wettest month and February the driest. Rain or snow falls on about 130 days a year.
About 191 frost-free days a year
In half of years the last 32° night comes by April 17 and the first one by October 26. That leaves about 191 frost-free days for gardens, longer than 65% of U.S. towns.
Heating and cooling a home in Cromwell
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Cromwell, 86% of that work is heating and 14% 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.
Cromwell and its neighbors
Cromwell borders 5 towns with climate data. January nights across them vary by 0.5°. Berlin has the coldest January nights (19°) and Rocky Hill the hottest July afternoons (85°). Cromwell’s January low is 20° and its July high 85°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Cromwell 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 Cromwell averaged 1.9° warmer than the 1900s. The biggest change is in December (+3.4°). The shift is larger than in 91% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Cromwell’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 16° to 37°. June is the most reliable, staying within 6°.
Common questions about Cromwell’s climate
What is the coldest month in Cromwell?
January, with a typical high of 37° and a low of 20°.
What is the hottest month in Cromwell?
July, with a typical high of 85° and a low of 63°. About 17 days a year reach 90°.
How much snow does Cromwell get?
About 52 inches in a normal winter, most of it in February.
When is the first frost in Cromwell?
In half of years the first 32° night comes by October 26, and the last spring frost by April 17.
What is the rainiest month in Cromwell?
October, with 4.5 inches of rain and melted snow. The year totals 46 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Cromwell itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Hartford Bradley Intl Airport, CT (22 mi, snow) and Hartford Brainard Fld, CT (8 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.