September Weather in Wilmington, United States

Last updated: June 24, 2025

In September, the average temperature in Wilmington, United States hovers around 19°C (67°F), with minimum and maximum extremes reaching 4°C (40°F) and 35°C (94°F), respectively. Expect about 79 mm (3.1 in) of precipitation over 7 days, accompanied by an average humidity level of 71%. Stay prepared for a mix of warm and refreshing weather!

September Temperature in Wilmington

In September in Wilmington, the average temperature is 19°C (67°F). Maximum temperatures can reach 35°C (94°F) and minimums can dip as low as 4°C (40°F). This variability suggests that travelers should pack accordingly for both warm days and cooler evenings.

September Weather in Wilmington: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Wilmington, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Wilmington, September typically has an average temperature of 19°C (67°F), with highs reaching up to 35°C (94°F) and lows dropping to around 4°C (40°F).

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

September Precipitation in Wilmington

In Wilmington in September, the total precipitation amount is 79 mm (3.1 in) distributed over a period of 7 days.

September Precipitation Trends in Wilmington

The chart displays monthly precipitation patterns in Wilmington, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Wilmington, September typically receives around 79 mm (3.1 inches) of precipitation spread over approximately 7 days.

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

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Millimeters (mm) Inches (in)

September Humidity in Wilmington

In Wilmington in September, humidity is 71%. With an average temperature of 19°C (67°F), this humidity feels like a warm embrace, making travel pleasant yet slightly sticky, as the air clings gently to your skin and invites you to stay hydrated while exploring.

September Average Humidity in Wilmington

This chart illustrates the average monthly humidity levels in Wilmington, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Wilmington is approximately 71%, offering insight into how humid the weather typically is during this month.

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

September UV Index in Wilmington

In Wilmington in September, the maximum UV index is 7, which corresponds to the high Exposure Category. This means that the time to burn is approximately 25 minutes. For more detailed information, you can check the Hourly UV Index in Wilmington.

Maximum UV Index Levels in Wilmington for September

The chart shows the monthly maximum UV Index (UVI) for Wilmington in September, 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 September, the maximum UV index in Wilmington typically reaches 7, which falls under the high exposure category.

Data source: Wilmington September 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 September Weather in Wilmington Compares to Other Months

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

This table compares monthly weather conditions in Wilmington, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-1°C (31°F)	71 mm (2.8 inches)	86%	moderate
February Weather	0°C (33°F)	87 mm (3.4 inches)	84%	moderate
March Weather	3°C (38°F)	89 mm (3.5 inches)	82%	moderate
April Weather	9°C (48°F)	127 mm (5.0 inches)	80%	very high
May Weather	15°C (59°F)	86 mm (3.4 inches)	72%	very high
June Weather	20°C (69°F)	85 mm (3.4 inches)	72%	very high
July Weather	23°C (74°F)	125 mm (4.9 inches)	67%	very high
August Weather	23°C (74°F)	79 mm (3.1 inches)	66%	very high
September Weather	19°C (67°F)	79 mm (3.1 inches)	71%	high
October Weather	13°C (56°F)	132 mm (5.2 inches)	78%	high
November Weather	6°C (43°F)	95 mm (3.7 inches)	84%	moderate
December Weather	1°C (34°F)	119 mm (4.7 inches)	81%	low