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
Grand Valley in September experiences a gentle temperature dip, with average high-temperatures reducing from a moderately hot 77.4°F (25.2°C) in August to a pleasant 71.4°F (21.9°C). Grand Valley, during the month of September, experiences an average low-temperature of 52.2°F (11.2°C).Humidity
In Grand Valley, the average relative humidity in September is 81%.Rainfall
In September, the rain falls for 14 days. Throughout September, 1.69" (43mm) of precipitation is accumulated. In Grand Valley, during the entire year, the rain falls for 160.2 days and collects up to 23.43" (595mm) 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 the month, sunrise is at 6:44 am and sunset at 7:51 pm. On the last day of September, sunrise is at 7:14 am and sunset at 7:01 pm EDT.
Sunshine
The average sunshine in September is 8.2h.UV index
In Grand Valley, 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 the ordinary person.Note: In September, the average maximum UV index of 3 translates into the following recommendations:
Undertake protective steps - Preventing sun damage is advised. For skin protection, it's recommended to minimize Sun exposure during its peak hours around midday. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in September?
What is the average humidity in September in Grand Valley?
How much does it rain in September?
When it does not snow?
Does it snow in September?
How many hours of daylight does Grand Valley have in September?
When is the sunrise / sunset in September?
How many hours of sunshine does Grand Valley have in September?
What is the UV index intensity in September?
Average temperature in September
Grand Valley, PA
- Average high temperature in September: 71.4°F
The warmest month (with the highest average high temperature) is July (78.8°F).
The month with the lowest average high temperature is January (29.5°F).
- Average low temperature in September: 52.2°F
The month with the highest average low temperature is July (58.6°F).
The coldest month (with the lowest average low temperature) is January (18°F).
Average pressure in September
Grand Valley, PA
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Grand Valley, PA
- Average wind speed in September: 6mph
The windiest month (with the highest average wind speed) is January (8.8mph).
The calmest month (with the lowest average wind speed) is July (5.4mph).
Average humidity in September
Grand Valley, PA
- Average humidity in September: 81%
The month with the highest relative humidity is February (90%).
The month with the lowest relative humidity is May (79%).
Average rainfall in September
Grand Valley, PA
- Average rainfall in September: 1.69"
The wettest month (with the highest rainfall) is April (2.32").
The driest month (with the least rainfall) is November (1.57").
Average rainfall days in September
Grand Valley, PA
- Average rainfall days in September: 14 days
The month with the highest number of rainy days is May (17.5 days).
The month with the least rainy days is February (7.5 days).
Average snowfall in September
Grand Valley, PA
- Average snowfall in September: 0"
The month with the highest snowfall is January (7.28").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Grand Valley, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (21.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Grand Valley, PA
- 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 1min
The months with the most sunshine are July and August (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 2h and 12min).
Average sunshine days in September
Grand Valley, PA
- Average sunshine days in September: 13.1 days
The month with the most sunshine days is October (13.3 days).
The month with the least sunshine days is January (5.3 days).
Average UV index in September
Grand Valley, PA
- Average UV index in September: 3
The months with the highest UV index are May, 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
Grand Valley, PA
- Average cloud cover in September: 42
The month with the most cloud cover is January (Cloud cover 78).
The months with the least cloud cover are July and August (Cloud cover 37).
Average visibility in September
Grand Valley, PA
- Average visibility in September: 5mi
The months with the highest visibility are March, April, May, June, July, August, September, October and November (5mi).
The months with the lowest visibility are January, February and December (4mi).
Grand Valley, Pennsylvania, USA
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