Cromwell (CT) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Cromwell.
Climate overview of Cromwell
Temperatures in Cromwell, Connecticut, United States of America, vary greatly throughout the year. July is the hottest month at 29°C (84°F), while January is the coldest at 3°C (37°F).
The city has a wet climate, receiving around 1303 mm (51 in) of rain/snowfall per year. Despite the high annual total, it has warm summers and cold winters. June is the wettest month. Sunshine peaks in July, when the city sees around 9.8 hours of sunshine per day.
Cromwell Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Cromwell - and find the best time to visit.
Monthly Temperature in Cromwell
The climate in Cromwell is known for significant temperature differences throughout the year, making the weather dynamic. On average, daytime temperatures range from a comfortable 29°C (84°F) in July to a chilly 3°C (37°F) in January.
Nighttime temperatures range from 19°C (66°F) in July to -7°C (19°F) in January.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Cromwell
Cromwell has a notably wet climate with abundant precipitation, recording 1303 mm (51 in) of rain/snowfall per year. The wettest period in Cromwell occurs in June, which receives around 147 mm (5.8 in) of precipitation. During the driest month, September, Cromwell experiences moderate rainfall, totaling 90 mm (3.5 in). The consistent precipitation levels throughout the year contribute to a relatively stable climate. For more details, please visit our Cromwell Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Sunshine Hours in Cromwell
In Cromwell, summer days are longer and more sunny, with daily sunshine hours peaking at 9.8 hours in July. As the darker season arrives, the brightness of the sun becomes less. November sees a soft sun for only 4.6 hours per average day.
Visit our detailed sunshine hours page for more information.
Monthly hours of sunshine
Daily hours of sunshine
Daily percentage of sunshine
Humidity in Cromwell by Month
The relative humidity is high throughout the year in Cromwell.
The city experiences its highest humidity in September, reaching 72%. In April, the humidity drops to its lowest level at 58%. What does this mean? Read our detailed page on humidity levels for further details.
Relative humidity over the year
Best Time to Visit Cromwell
Monthly ratings reflect general weather comfort, based on daytime temperature and rainfall. Swimming and winter conditions are highlighted separately where relevant.
- Best overall: May and September
- Warmest weather: July and August
- Most sunshine: July
- Seasonal pattern: Warm summers and cold winters
- Coldest conditions: January, with freezing nights around -7°C (19°F).
Frequently asked questions about the climate in Cromwell
What is the best time to visit Cromwell?
May and September typically offer the most optimal weather in Cromwell. In contrast, January, February, March and December tend to have less optimal conditions. Cromwell has warm summers and cold winters.
What temperatures can I expect in Cromwell?
Daytime highs range from 3°C (37°F) in January to 29°C (84°F) in July. Nighttime lows range from -7°C (19°F) to 19°C (66°F). Temperatures vary considerably through the year.
How much rain does Cromwell get?
Annual rainfall is around 1303 mm (51 in). June is the wettest month with 147 mm (5.8 in), while September is the driest with 90 mm (3.5 in).
How sunny is Cromwell?
Cromwell receives around 2,579 hours of sunshine per year. July is the sunniest month with 293 hours, while November is the cloudiest with just 139 hours. Overall, Cromwell enjoys abundant sunshine.
Cromwell 3-Day Forecast
Cromwell (CT) 3-Day Forecast
Cromwell on the map
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