September weather forecastSylmar, PA
September
Weather in September
The first month of the autumn, September, is also a moderately hot month in Sylmar, Pennsylvania, with an average temperature varying between 75.2°F (24°C) and 58.1°F (14.5°C).Temperature
A modest decline in the average high-temperature is seen during September, decreasing from 81.3°F (27.4°C) in August to a still moderately hot 75.2°F (24°C). Sylmar, in September, observes a steady average low-temperature of 58.1°F (14.5°C).Humidity
The average relative humidity in September is 80%.Rainfall
In Sylmar, in September, during 11.4 rainfall days, 1.1" (28mm) of precipitation is typically accumulated. Throughout the year, there are 130.4 rainfall days, and 16.3" (414mm) of precipitation is accumulated.Snowfall
In Sylmar, snow does not fall in May through October.Daylight
In Sylmar, the average length of the day in September is 12h and 26min.On the first day of September, sunrise is at 6:32 am and sunset at 7:34 pm. On the last day of the month, sunrise is at 7:00 am and sunset at 6:47 pm EDT.
Sunshine
The average sunshine in September is 8.9h.UV index
In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from unsafe exposure to UV radiation for ordinary individuals.Note: The daily high UV index of 4 in September translates into this advice:
Guard yourself - Precautionary measures against sun damage are advocated. During midday, the Sun's radiation is strongest, and it's advisable to reduce direct exposure. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Sylmar, PA
- Average high temperature in September: 75.2°F
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is January (36.7°F).
- Average low temperature in September: 58.1°F
The month with the highest average low temperature is July (65.8°F).
The coldest month (with the lowest average low temperature) is January (24.6°F).
Average pressure in September
Sylmar, PA
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in September
Sylmar, PA
- Average wind speed in September: 5.8mph
The windiest months (with the highest average wind speed) are January, February and March (8.9mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).
Average humidity in September
Sylmar, PA
- Average humidity in September: 80%
The month with the highest relative humidity is May (81%).
The months with the lowest relative humidity are January, March, April and November (76%).
Average rainfall in September
Sylmar, PA
- Average rainfall in September: 1.1"
The wettest month (with the highest rainfall) is August (2.36").
The driest month (with the least rainfall) is January (0.91").
Average rainfall days in September
Sylmar, PA
- Average rainfall days in September: 11.4 days
The month with the highest number of rainy days is May (15.1 days).
The month with the least rainy days is January (6 days).
Average snowfall in September
Sylmar, PA
- Average snowfall in September: 0"
The month with the highest snowfall is March (1.61").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in September
Sylmar, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (4.8 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
Sylmar, PA
- Average daylight in September: 12h and 24min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in September: 8h and 54min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in September
Sylmar, PA
- Average sunshine days in September: 16.5 days
The month with the most sunshine days is November (21.8 days).
The month with the least sunshine days is June (13.2 days).
Average UV index in September
Sylmar, PA
- Average UV index in September: 4
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, November and December (UV index 2).
Average cloud cover in September
Sylmar, PA
- Average cloud cover in September: 37
The months with the most cloud cover are February, March and May (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 32).
Average visibility in September
Sylmar, PA
- Average visibility in September: 5mi
The months with the highest visibility are January, February, March, April, June, July, October, November and December (6mi).
The months with the lowest visibility are May, August and September (5mi).





