Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
With the onset of September, Great Valley's climate undergoes a slight change as the average high-temperature moves from a warm 76.3°F (24.6°C) in August to a pleasant 69.6°F (20.9°C). In the month of September, the nighttime temperature dips to a steady average of 50.2°F (10.1°C).Humidity
In September, the average relative humidity in Great Valley is 81%.Rainfall
The month with the least rainfall in Great Valley is September, when the rain falls for 14.4 days and typically collects 1.69" (43mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 28min.On the first day of September, sunrise is at 6:40 am and sunset at 7:47 pm. On the last day of the month, sunrise is at 7:11 am and sunset at 6:57 pm EDT.
Sunshine
In September, the average sunshine is 8.4h.UV index
In Great Valley, New York, the average daily maximum UV index in September is 3. A UV Index estimate of 3 to 5 represents a moderate health risk from unsafe exposure to UV radiation for average individuals.Note: The maximum UV index of 3 during September leads to these instructions:
Stay alert. Light-skinned people could suffer burns in less than 30 minutes. During midday, the Sun's radiation is strongest, and it's advisable to reduce direct exposure. Always opt for UVA and UVB-resistant sunglasses on radiant days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average September temperature in Great Valley?
What is the average humidity in September in Great Valley?
What is the driest month in Great Valley?
How much does it rain in Great Valley in September?
When it does not snow in Great Valley?
Does it snow in Great Valley in September?
How many hours of daylight does Great Valley have in September?
What time are sunrise and sunset in September in Great Valley?
How long on average sun shines in September in Great Valley?
How high is the UV index in September in Great Valley?
Average temperature in September
Great Valley, NY
- Average high temperature in September: 69.6°F
The warmest month (with the highest average high temperature) is July (77.5°F).
The month with the lowest average high temperature is January (28°F).
- Average low temperature in September: 50.2°F
The month with the highest average low temperature is July (57°F).
The coldest month (with the lowest average low temperature) is January (16.2°F).
Average pressure in September
Great Valley, NY
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Great Valley, NY
- Average wind speed in September: 6.3mph
The windiest month (with the highest average wind speed) is January (10mph).
The calmest month (with the lowest average wind speed) is August (5.9mph).
Average humidity in September
Great Valley, NY
- Average humidity in September: 81%
The months with the highest relative humidity are January and February (89%).
The month with the lowest relative humidity is May (79%).
Average rainfall in September
Great Valley, NY
- Average rainfall in September: 1.69"
The wettest month (with the highest rainfall) is April (3.27").
The driest month (with the least rainfall) is September (1.69").
Average rainfall days in September
Great Valley, NY
- Average rainfall days in September: 14.4 days
The month with the highest number of rainy days is May (18.1 days).
The month with the least rainy days is January (6.7 days).
Average snowfall in September
Great Valley, NY
- Average snowfall in September: 0"
The month with the highest snowfall is February (8.98").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Great Valley, NY
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (18.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Great Valley, NY
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in September: 8h and 2min
The months with the most sunshine are July and August (Average sunshine: 9h and 42min).
The month with the least sunshine is January (Average sunshine: 2h and 18min).
Average sunshine days in September
Great Valley, NY
- Average sunshine days in September: 13.3 days
The month with the most sunshine days is September (13.3 days).
The month with the least sunshine days is January (8.3 days).
Average UV index in September
Great Valley, NY
- Average UV index in September: 3
The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, February and December (UV index 1).
Average cloud cover in September
Great Valley, NY
- Average cloud cover in September: 42
The month with the most cloud cover is January (Cloud cover 79).
The months with the least cloud cover are July and August (Cloud cover 39).
Average visibility in September
Great Valley, NY
- Average visibility in September: 5mi
The months with the highest visibility are March, April, May, June, July, August, September, October, November and December (5mi).
The months with the lowest visibility are January and February (4mi).
Great Valley, New York, USA
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