September weather forecastHenlopen Acres, DE
September
Weather in September
September in Henlopen Acres brings a slight dip in temperature, signaling the initiation of the fall season. The end of summer sees a noticeable decrease in rainfall with only 0.28" (7mm) accounted for, the lowest in the year. With mild winds and low humidity, it's the perfect time for hikes and outdoor exploration. Expect the blue sky to dominate most days as clouds find little room to feature. Sunset watching becomes a popular activity, with red and orange hues routinely painting the evening sky.Temperature
Henlopen Acres notes an average high-temperature of a still moderately hot 74.1°F (23.4°C) in September, displaying minor variation from August. September nights in Henlopen Acres experience a minor temperature downturn to a comfortable 67.8°F (19.9°C).Humidity
In September, the average relative humidity is 78%.Rainfall
The month with the least rainfall in Henlopen Acres is September, when the rain falls for 7.5 days and typically collects 0.28" (7mm) of precipitation.Snowfall
In Henlopen Acres, snow does not fall in April through October.Daylight
In September, the average length of the day in Henlopen Acres is 12h and 26min.On the first day of the month, sunrise is at 6:30 am and sunset at 7:30 pm. On the last day of September, in Henlopen Acres, sunrise is at 6:55 am and sunset at 6:44 pm EDT.
Sunshine
In September, the average sunshine is 9.6h.UV index
In Henlopen Acres, the average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for the average person.Note: A maximum high daily UV index of 5 during September translates into the following directions:
Safety measures are advised. Light-skinned individuals may experience burns in under half an hour. The Sun's most harmful UV rays are emitted around midday; avoid staying outdoors for long during this time. On days when the sun blazes, arm yourself with sunglasses that block UVA and UVB radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Henlopen Acres, DE
- Average high temperature in September: 74.1°F
The warmest month (with the highest average high temperature) is July (80.2°F).
The month with the lowest average high temperature is January (41.4°F).
- Average low temperature in September: 67.8°F
The month with the highest average low temperature is July (73.6°F).
The coldest month (with the lowest average low temperature) is January (33.1°F).
Average pressure in September
Henlopen Acres, DE
- Average pressure in September: 30.04"Hg
The month with the highest atmospheric pressure is November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Henlopen Acres, DE
- Average wind speed in September: 10.6mph
The windiest month (with the highest average wind speed) is January (13mph).
The calmest month (with the lowest average wind speed) is August (8.8mph).
Average humidity in September
Henlopen Acres, DE
- Average humidity in September: 78%
The month with the highest relative humidity is May (82%).
The month with the lowest relative humidity is November (73%).
Average rainfall in September
Henlopen Acres, DE
- Average rainfall in September: 0.28"
The wettest month (with the highest rainfall) is October (0.71").
The driest month (with the least rainfall) is September (0.28").
Average rainfall days in September
Henlopen Acres, DE
- Average rainfall days in September: 7.5 days
The month with the highest number of rainy days is July (10.2 days).
The month with the least rainy days is November (4.9 days).
Average snowfall in September
Henlopen Acres, DE
- Average snowfall in September: 0"
The months with the highest snowfall are January and December (0.12").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Henlopen Acres, DE
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (2.4 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Henlopen Acres, DE
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in September: 9h and 36min
The month with the most sunshine is July (Average sunshine: 11h and 6min).
The month with the least sunshine is February (Average sunshine: 5h and 0min).
Average sunshine days in September
Henlopen Acres, DE
- Average sunshine days in September: 20 days
The month with the most sunshine days is January (23.5 days).
The months with the least sunshine days are June and July (18.2 days).
Average UV index in September
Henlopen Acres, DE
- Average UV index in September: 5
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February and December (UV index 2).
Average cloud cover in September
Henlopen Acres, DE
- Average cloud cover in September: 30
The month with the most cloud cover is February (Cloud cover 45).
The month with the least cloud cover is July (Cloud cover 24).
Average visibility in September
Henlopen Acres, DE
- Average visibility in September: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
