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
A subtle change in temperatures is noted as August gives way to September, with average highs reducing from a moderately hot 78.6°F (25.9°C) to a pleasant 72.3°F (22.4°C). September records a small disparity from daytime temperatures, marking an average low-temperature of 64.8°F (18.2°C).Humidity
The average relative humidity in September is 74%.Rainfall
In September, the rain falls for 13.5 days. Throughout September, 2.64" (67mm) of precipitation is accumulated. Throughout the year, there are 155.9 rainfall days, and 35.94" (913mm) of precipitation is accumulated.Snowfall
April through October are months without snowfall.Daylight
In Smithtown, the average length of the day in September is 12h and 27min.On the first day of September in Smithtown, sunrise is at 6:20 am and sunset at 7:24 pm. On the last day of the month, sunrise is at 6:49 am and sunset at 6:36 pm EDT.
Sunshine
The average sunshine in September in Smithtown, New York, is 9.1h.UV index
In September, the average daily maximum UV index is 5. A UV Index of 3 to 5 symbolizes a medium health hazard from unsafe exposure to UV radiation for ordinary individuals.Note: The maximum daily UV index of 5 in September converts into the following recommendations:
Take necessary precautions - Suggestions to elude sunburn are provided. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. Experience reduced UV exposure by about half when donning a wide-brim hat.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the temperature in September?
What is the average humidity in September?
How many days does it rain in September?
When it does not snow?
How many hours of daylight does Smithtown have in September?
When is the sunrise / sunset in September?
How long on average sun shines in September?
What is the UV index reading in September?
Average temperature in September
Smithtown, NY
- Average high temperature in September: 72.3°F
The warmest month (with the highest average high temperature) is July (79.3°F).
The month with the lowest average high temperature is January (37.6°F).
- Average low temperature in September: 64.8°F
The month with the highest average low temperature is August (71.6°F).
The coldest month (with the lowest average low temperature) is January (28.9°F).
Average pressure in September
Smithtown, NY
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in September
Smithtown, NY
- Average wind speed in September: 9.6mph
The windiest month (with the highest average wind speed) is January (12.8mph).
The calmest month (with the lowest average wind speed) is July (8.3mph).
Average humidity in September
Smithtown, 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 (71%).
Average rainfall in September
Smithtown, NY
- Average rainfall in September: 2.64"
The wettest month (with the highest rainfall) is July (3.94").
The driest month (with the least rainfall) is January (2.2").
Average rainfall days in September
Smithtown, NY
- Average rainfall days in September: 13.5 days
The month with the highest number of rainy days is July (17.4 days).
The month with the least rainy days is January (7.8 days).
Average snowfall in September
Smithtown, NY
- Average snowfall in September: 0"
The month with the highest snowfall is March (1.85").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in September
Smithtown, NY
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (4.8 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
Smithtown, NY
- Average daylight in September: 12h and 3min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in September: 9h and 1min
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
Smithtown, NY
- Average sunshine days in September: 14.7 days
The month with the most sunshine days is November (19.4 days).
The month with the least sunshine days is July (11.4 days).
Average UV index in September
Smithtown, 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 and December (UV index 2).
Average cloud cover in September
Smithtown, NY
- Average cloud cover in September: 32
The month with the most cloud cover is December (Cloud cover 48).
The month with the least cloud cover is August (Cloud cover 28).
Average visibility in September
Smithtown, 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).
Smithtown, New York, USA
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