September weather forecastWilliamsport, MD
September
Weather in September
September, the first month of the autumn in Williamsport, is still a warm month, with an average temperature ranging between max 76.1°F (24.5°C) and min 56.3°F (13.5°C).Temperature
Williamsport's weather in September involves a mild decrease in the average high-temperature, moving down slightly from August's moderately hot 83.1°F (28.4°C) to a still warm 76.1°F (24.5°C). Williamsport's nighttime temperature in September falls to an average of 56.3°F (13.5°C).Humidity
In September, the average relative humidity is 78%.Rainfall
September is the month with the least rainfall. Rain falls for 12.5 days and accumulates 1.61" (41mm) of precipitation.Snowfall
May through October are months without snowfall.Daylight
The average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 6:40 am and sunset at 7:41 pm. On the last day of September, sunrise is at 7:07 am and sunset at 6:54 pm EDT.
Sunshine
The average sunshine in September is 8.8h.UV index
In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV rays for the ordinary person.Note: The daily maximum UV index of 4 in September interprets into the following advice:
Make use of precautions - It is urged to ward off sun damage. To protect against the Sun's most potent rays, avoid direct exposure around midday. Wearing sunglasses with both UVA and UVB protection effectively reduces sun-induced eye damage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Williamsport, MD
- Average high temperature in September: 76.1°F
The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (36.9°F).
- Average low temperature in September: 56.3°F
The month with the highest average low temperature is July (64°F).
The coldest month (with the lowest average low temperature) is January (23.4°F).
Average pressure in September
Williamsport, MD
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in September
Williamsport, MD
- Average wind speed in September: 4.9mph
The windiest month (with the highest average wind speed) is January (7.5mph).
The calmest month (with the lowest average wind speed) is August (4.3mph).
Average humidity in September
Williamsport, MD
- Average humidity in September: 78%
The month with the highest relative humidity is October (79%).
The month with the lowest relative humidity is July (74%).
Average rainfall in September
Williamsport, MD
- Average rainfall in September: 1.61"
The wettest month (with the highest rainfall) is May (2.91").
The driest month (with the least rainfall) is September (1.61").
Average rainfall days in September
Williamsport, MD
- Average rainfall days in September: 12.5 days
The month with the highest number of rainy days is May (17.6 days).
The month with the least rainy days is January (8.2 days).
Average snowfall in September
Williamsport, MD
- Average snowfall in September: 0"
The month with the highest snowfall is January (3.58").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Williamsport, MD
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (6.2 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
Williamsport, MD
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in September: 8h and 48min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The months with the least sunshine are January and February (Average sunshine: 4h and 48min).
Average sunshine days in September
Williamsport, MD
- Average sunshine days in September: 15.1 days
The month with the most sunshine days is November (19.6 days).
The month with the least sunshine days is May (11.7 days).
Average UV index in September
Williamsport, MD
- Average UV index in September: 4
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, November and December (UV index 2).
Average cloud cover in September
Williamsport, MD
- Average cloud cover in September: 38
The month with the most cloud cover is January (Cloud cover 49).
The month with the least cloud cover is July (Cloud cover 31).
Average visibility in September
Williamsport, MD
- Average visibility in September: 5mi
The months with the highest visibility are February, March, April, June, July, August, November and December (6mi).
The months with the lowest visibility are January, May, September and October (5mi).
