September weather forecastRoslyn, PA
September
Weather in September
The first month of the autumn, September, is still a warm month in Roslyn, Pennsylvania, with an average temperature ranging between min 59.9°F (15.5°C) and max 76.1°F (24.5°C).Temperature
As September commences, the average high-temperature subtly reduces, transitioning from a warm 83.3°F (28.5°C) in August to a still moderately hot 76.1°F (24.5°C). During September, Roslyn records an average temperature of 59.9°F (15.5°C) at night.Humidity
In Roslyn, the average relative humidity in September is 75%.Rainfall
September is the month with the least rainfall. Rain falls for 10.1 days and accumulates 0.75" (19mm) of precipitation.Snowfall
In Roslyn, Pennsylvania, snow does not fall in May through October.Daylight
The average length of the day in September is 12h and 26min.On the first day of the month, sunrise is at 6:28 am and sunset at 7:31 pm. On the last day of September, sunrise is at 6:56 am and sunset at 6:43 pm EDT.
Sunshine
In Roslyn, the average sunshine in September is 8.8h.UV index
In Roslyn, the average daily maximum UV index in September is 5. A UV Index of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV radiation for average individuals.Note: In September, the maximum UV index of 5 suggests this advice:
Be vigilant - Suggestions to stave off sun damage are provided. It's recommended to limit sun exposure when its radiation is at its peak during midday. For holistic sun protection encompassing the eyes, ears, face, and neck, a wide-brim hat is key.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Roslyn, PA
- Average high temperature in September: 76.1°F
The warmest month (with the highest average high temperature) is July (86.2°F).
The month with the lowest average high temperature is January (36.7°F).
- Average low temperature in September: 59.9°F
The month with the highest average low temperature is July (68.2°F).
The coldest month (with the lowest average low temperature) is January (24.6°F).
Average pressure in September
Roslyn, PA
- Average pressure in September: 30.05"Hg
The month with the highest atmospheric pressure is November (30.12"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Roslyn, PA
- Average wind speed in September: 5.8mph
The windiest month (with the highest average wind speed) is March (8.4mph).
The calmest month (with the lowest average wind speed) is August (5.4mph).
Average humidity in September
Roslyn, PA
- Average humidity in September: 75%
The months with the highest relative humidity are February, October and December (78%).
The months with the lowest relative humidity are April, July and August (72%).
Average rainfall in September
Roslyn, PA
- Average rainfall in September: 0.75"
The wettest month (with the highest rainfall) is August (1.54").
The driest month (with the least rainfall) is September (0.75").
Average rainfall days in September
Roslyn, PA
- Average rainfall days in September: 10.1 days
The month with the highest number of rainy days is May (14.1 days).
The month with the least rainy days is November (6.4 days).
Average snowfall in September
Roslyn, PA
- Average snowfall in September: 0"
The month with the highest snowfall is February (1.46").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Roslyn, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (5.1 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Roslyn, PA
- Average daylight in September: 12h and 24min
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 24min).
- Average sunshine in September: 8h and 48min
The month with the most sunshine is July (Average sunshine: 10h and 42min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in September
Roslyn, PA
- Average sunshine days in September: 18.5 days
The month with the most sunshine days is November (21.3 days).
The month with the least sunshine days is May (14.4 days).
Average UV index in September
Roslyn, PA
- Average UV index in September: 5
The months with the highest UV index are May, 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
Roslyn, PA
- Average cloud cover in September: 38
The month with the most cloud cover is February (Cloud cover 48).
The month with the least cloud cover is July (Cloud cover 31).
Average visibility in September
Roslyn, PA
- Average visibility in September: 5mi
The months with the highest visibility are January, February, March, April, June, July, August, October, November and December (6mi).
The months with the lowest visibility are May and September (5mi).





