September weather forecastLewiston, NY
September
Weather in September
The first month of the autumn, September, is still a pleasant month in Lewiston, New York, with an average temperature ranging between max 70.9°F (21.6°C) and min 59.2°F (15.1°C).Temperature
The onset of September brings a small shift in high-temperatures, falling from a moderately hot 77.2°F (25.1°C) in August to an agreeable 70.9°F (21.6°C). Throughout the month of September, Lewiston witnesses an average temperature of 59.2°F (15.1°C).Humidity
The months with the lowest humidity are August and September, with an average relative humidity of 74%.Rainfall
September is the month with the least rainfall in Lewiston. Rain falls for 13.7 days and accumulates 1.85" (47mm) of precipitation.Snowfall
June through September are months without snowfall.Daylight
In September, the average length of the day is 12h and 29min.On the first day of the month, sunrise is at 6:41 am and sunset at 7:50 pm. On the last day of September, in Lewiston, sunrise is at 7:13 am and sunset at 6:58 pm EDT.
Sunshine
In Lewiston, New York, the average sunshine in September is 9.3h.UV index
The average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a moderate health risk from exposure to the Sun's UV rays for the average person.Note: A maximum high UV index of 4 in September translates into the following recommendations:
Ensure safety - Sun damage prevention is strongly urged. The intensity of the Sun's UV radiation during midday suggests reducing time spent outdoors. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Lewiston, NY
- Average high temperature in September: 70.9°F
The warmest month (with the highest average high temperature) is July (78.1°F).
The month with the lowest average high temperature is January (29.7°F).
- Average low temperature in September: 59.2°F
The month with the highest average low temperature is August (64.9°F).
The coldest month (with the lowest average low temperature) is January (20.5°F).
Average pressure in September
Lewiston, NY
- Average pressure in September: 30.04"Hg
The month with the highest atmospheric pressure is November (30.08"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in September
Lewiston, NY
- Average wind speed in September: 8.2mph
The windiest month (with the highest average wind speed) is January (12.3mph).
The calmest month (with the lowest average wind speed) is July (7.1mph).
Average humidity in September
Lewiston, NY
- Average humidity in September: 74%
The month with the highest relative humidity is February (84%).
The months with the lowest relative humidity are August and September (74%).
Average rainfall in September
Lewiston, NY
- Average rainfall in September: 1.85"
The wettest month (with the highest rainfall) is July (3.11").
The driest month (with the least rainfall) is September (1.85").
Average rainfall days in September
Lewiston, NY
- Average rainfall days in September: 13.7 days
The month with the highest number of rainy days is May (17.6 days).
The month with the least rainy days is February (7.8 days).
Average snowfall in September
Lewiston, NY
- Average snowfall in September: 0"
The month with the highest snowfall is February (7.13").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in September
Lewiston, NY
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (16.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in September /
Average sunshine in September
Lewiston, NY
- Average daylight in September: 12h and 30min
The month with the longest days is June (Average daylight: 15h and 18min).
The month with the shortest days is December (Average daylight: 9h and 6min).
- Average sunshine in September: 9h and 18min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 2h and 42min).
Average sunshine days in September
Lewiston, NY
- Average sunshine days in September: 14 days
The month with the most sunshine days is September (14 days).
The month with the least sunshine days is January (6.8 days).
Average UV index in September
Lewiston, NY
- Average UV index in September: 4
The months with the highest UV index are July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in September
Lewiston, NY
- Average cloud cover in September: 32
The month with the most cloud cover is January (Cloud cover 74).
The month with the least cloud cover is August (Cloud cover 28).
Average visibility in September
Lewiston, NY
- Average visibility in September: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January and February (5mi).





