January Weather in Delaware, United States

Last updated: June 24, 2025

In January, the average temperature in Delaware, United States hovers around -1°C (30°F). Prepare for a chilly climate where temperatures can plunge to a frigid -24°C (-10°F) or rise up to a surprisingly warm 21°C (70°F). Expect 78 mm (3.1 in) of precipitation spread over approximately 10 days, with an average humidity of a damp 88%.

January Temperature in Delaware

In January in Delaware, the average temperature is -1°C (30°F), with maximums reaching 21°C (70°F) and minimums plummeting to -24°C (-10°F). Be prepared for a wide range of temperatures if you plan to travel during this time!

January Weather in Delaware: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in Delaware, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Delaware, January typically has an average temperature of -1°C (30°F), with highs reaching up to 21°C (70°F) and lows dropping to around -24°C (-10°F).

Data source: Temperature data for Delaware generated using information from the Copernicus Climate Change Service.

January Precipitation in Delaware

In Delaware in January, the precipitation amount is 78 mm (3.1 in) over the course of 10 days.

January Precipitation Trends in Delaware

The chart displays monthly precipitation patterns in Delaware, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In Delaware, January typically receives around 78 mm (3.1 inches) of precipitation spread over approximately 10 days.

Data source: Precipitation data for January generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

January Humidity in Delaware

In Delaware in January humidity is 88%. With an average temperature of -1°C (30°F), this humidity feels like a biting chill that penetrates through your layers, making travel uncomfortable as every gust of wind becomes a sharp reminder of the cold and damp air surrounding you.

January Average Humidity in Delaware

This chart illustrates the average monthly humidity levels in Delaware, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in Delaware is approximately 88%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for January generated using information from the Copernicus Climate Change Service.

January UV Index in Delaware

In Delaware in January, the maximum UV index is 3, which corresponds to a moderate Exposure Category. The time to burn is approximately 30 minutes. For more details on the hourly UV index in Delaware, you can check the information here.

Maximum UV Index Levels in Delaware for January

The chart shows the monthly maximum UV Index (UVI) for Delaware in January, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In January, the maximum UV index in Delaware typically reaches 3, which falls under the moderate exposure category.

Data source: Delaware January UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How January Weather in Delaware Compares to Other Months

Weather in Delaware varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in Delaware, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Delaware, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-1°C (30°F)	78 mm (3.1 inches)	88%	moderate
February Weather	1°C (34°F)	104 mm (4.1 inches)	87%	moderate
March Weather	5°C (42°F)	105 mm (4.1 inches)	87%	high
April Weather	11°C (52°F)	116 mm (4.6 inches)	87%	very high
May Weather	17°C (63°F)	124 mm (4.9 inches)	81%	very high
June Weather	22°C (72°F)	144 mm (5.7 inches)	82%	very high
July Weather	24°C (76°F)	111 mm (4.4 inches)	81%	very high
August Weather	23°C (73°F)	74 mm (2.9 inches)	78%	very high
September Weather	20°C (69°F)	86 mm (3.4 inches)	78%	very high
October Weather	14°C (58°F)	99 mm (3.9 inches)	82%	high
November Weather	5°C (42°F)	96 mm (3.8 inches)	89%	moderate
December Weather	2°C (36°F)	97 mm (3.8 inches)	86%	moderate