September weather forecastValley Stream, NY
September
Weather in September
The transition from summer to autumn is perceived in September in Valley Stream. Average high temperature decreases to 73.2°F (22.9°C), indicating the onset of cooler days. Despite the drop in temperatures, the extended daylight hours persist, making it a favorable month for outdoor activities. The whispering winds of fall begin to scatter leaves, painting a beautiful canvas of changing colors. The shift from the fiery summer to a cooler, more tranquil season starts to take place.Temperature
The start of September involves a subtle temperature drop, shifting from a moderately hot 79.9°F (26.6°C) in August to an agreeable 73.2°F (22.9°C). September sees a slight dip to an average low temperature of 64.2°F (17.9°C) from the daytime highs.Humidity
The average relative humidity in September is 74%.Rainfall
In Valley Stream, in September, during 12.4 rainfall days, 1.38" (35mm) of precipitation is typically accumulated. In Valley Stream, during the entire year, the rain falls for 135.3 days and collects up to 18.62" (473mm) of precipitation.Snowfall
April through September are months without snowfall.Daylight
In Valley Stream, the average length of the day in September is 12h and 27min.On the first day of the month, sunrise is at 6:22 am and sunset at 7:26 pm. On the last day of September, sunrise is at 6:51 am and sunset at 6:38 pm EDT.
Sunshine
In September, the average sunshine is 9.1h.UV index
In September, the average daily maximum UV index is 5. A UV Index reading of 3 to 5 represents a moderate threat to health from unsafe exposure to UV radiation for the ordinary person.Note: In September, the average maximum UV index of 5 translates into the following recommendations:
Exercise prevention - Protecting skin and eyes from harm is required. During midday, the Sun's radiation is strongest, and it's advisable to reduce direct exposure. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Valley Stream, NY
- Average high temperature in September: 73.2°F
The warmest month (with the highest average high temperature) is July (80.6°F).
The month with the lowest average high temperature is January (37°F).
- Average low temperature in September: 64.2°F
The month with the highest average low temperature is August (71.1°F).
The coldest month (with the lowest average low temperature) is January (28.2°F).
Average pressure in September
Valley Stream, NY
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Valley Stream, NY
- Average wind speed in September: 9.1mph
The windiest month (with the highest average wind speed) is January (12.4mph).
The calmest month (with the lowest average wind speed) is July (8mph).
Average humidity in September
Valley Stream, NY
- Average humidity in September: 74%
The month with the highest relative humidity is May (77%).
The month with the lowest relative humidity is November (72%).
Average rainfall in September
Valley Stream, NY
- Average rainfall in September: 1.38"
The wettest months (with the highest rainfall) are July and August (2.32").
The driest month (with the least rainfall) is January (0.91").
Average rainfall days in September
Valley Stream, NY
- Average rainfall days in September: 12.4 days
The month with the highest number of rainy days is July (15.1 days).
The month with the least rainy days is January (7.3 days).
Average snowfall in September
Valley Stream, NY
- Average snowfall in September: 0"
The month with the highest snowfall is March (1.02").
The months with the least snowfall are April, May, June, July, August and September (0").
Average snowfall days in September
Valley Stream, NY
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (4.6 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Valley Stream, NY
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 9h and 6min
The month with the most sunshine is July (Average sunshine: 10h and 48min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in September
Valley Stream, NY
- Average sunshine days in September: 15.6 days
The month with the most sunshine days is January (19.8 days).
The month with the least sunshine days is July (13.6 days).
Average UV index in September
Valley Stream, NY
- Average UV index in September: 5
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in September
Valley Stream, NY
- Average cloud cover in September: 32
The months with the most cloud cover are February and December (Cloud cover 47).
The month with the least cloud cover is August (Cloud cover 27).
Average visibility in September
Valley Stream, NY
- 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).
