New Castle (DE) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit New Castle.
Climate overview of New Castle
Temperatures in New Castle, Delaware, United States of America, vary greatly throughout the year. July is the hottest month at 31°C (88°F), while February is the coldest at 5°C (41°F).
The city has a wet climate, receiving around 1233 mm (49 in) of rain/snowfall per year. June is the wettest month. July is the sunniest month, averaging 9.2 hours of sunshine per day.
New Castle Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in New Castle — and find the best time to visit.
Monthly Temperature in New Castle
The climate in New Castle is known for significant temperature differences throughout the year, making the weather dynamic. On average, daytime temperatures range from a very warm 31°C (88°F) in July to a chilly 5°C (41°F) in February.
Nighttime temperatures range from 21°C (70°F) in July to -4°C (25°F) in February.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in New Castle
New Castle has a notably wet climate with abundant precipitation, recording 1233 mm (49 in) of rain/snowfall per year. The amount of precipitation varies moderately throughout the year. The wettest month, June, sees around 145 mm (5.7 in) of rainfall, perfect for those who enjoy a bit of rain now and then. The driest month, November, still receives a respectable 75 mm (3 in) of rainfall. For more details, please visit our New Castle 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 New Castle
In New Castle, summer days are longer and more sunny, with daily sunshine hours peaking at 9.2 hours in July. As the darker season arrives, the brightness of the sun becomes less. December sees a soft sun for only 4.7 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 New Castle by Month
The relative humidity is high throughout the year in New Castle.
The city experiences its highest humidity in September, reaching 72%. In April, the humidity drops to its lowest level at 61%. What does this mean? Read our detailed page on humidity levels for further details.
Relative humidity over the year
Best Time to Visit New Castle
Frequently asked questions about the climate in New Castle
What is the best time to visit New Castle?
May typically offers the most optimal weather in New Castle. In contrast, January, February and December tend to have less optimal conditions.
What temperatures can I expect in New Castle?
Daytime highs range from 5°C (41°F) in February to 31°C (88°F) in July. Nighttime lows range from -4°C (25°F) to 21°C (70°F). Temperatures vary considerably through the year.
How much rain does New Castle get?
Annual rainfall is around 1233 mm (49 in). June is the wettest month with 145 mm (5.7 in), while November is the driest with 75 mm (3 in).
How sunny is New Castle?
New Castle receives around 2,500 hours of sunshine per year. July is the sunniest month with 275 hours, while December is the cloudiest with just 140 hours. Overall, New Castle enjoys abundant sunshine.
New Castle 3-Day Forecast
New Castle (DE) 3-Day Forecast
New Castle on the map
New Castle is highlighted — select any city to see its climate.
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