September weather forecastSaint Thomas, PA
September
Weather in September
September, the first month of the autumn in Saint Thomas, is still a warm month, with an average temperature fluctuating between 55.6°F (13.1°C) and 74.8°F (23.8°C).Temperature
A modest decline in the average high-temperature is seen during September, decreasing from a warm 81.9°F (27.7°C) in August to a still moderately hot 74.8°F (23.8°C). Throughout the month of September, Saint Thomas witnesses an average low-temperature of 55.6°F (13.1°C).Humidity
In September, the average relative humidity is 78%.Rainfall
In Saint Thomas, during September, the rain falls for 14.1 days and regularly aggregates up to 1.97" (50mm) of precipitation. In Saint Thomas, during the entire year, the rain falls for 161.8 days and collects up to 28.07" (713mm) of precipitation.Snowfall
In Saint Thomas, snow does not fall in May through September.Daylight
The average length of the day in September is 12h and 26min.On the first day of September, sunrise is at 6:39 am and sunset at 7:42 pm. On the last day of the month, sunrise is at 7:07 am and sunset at 6:54 pm EDT.
Sunshine
In Saint Thomas, the average sunshine in September is 8.6h.UV index
The average daily maximum UV index in September is 4. A UV Index value of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV rays for average individuals.Note: A maximum UV index of 4 in September translates into the following recommendations:
Be vigilant - A duty to shield skin and eyes from injury exists. Considering the Sun's intensity during midday, it's wise to minimize direct exposure. During bright days, sunglasses that offer UVA and UVB defense are recommended.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Saint Thomas, PA
- Average high temperature in September: 74.8°F
The warmest month (with the highest average high temperature) is July (84.4°F).
The month with the lowest average high temperature is January (35.4°F).
- Average low temperature in September: 55.6°F
The month with the highest average low temperature is July (62.6°F).
The coldest month (with the lowest average low temperature) is January (22.5°F).
Average pressure in September
Saint Thomas, PA
- Average pressure in September: 30.06"Hg
The month with the highest atmospheric pressure is November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in September
Saint Thomas, PA
- Average wind speed in September: 5mph
The windiest month (with the highest average wind speed) is January (7.7mph).
The calmest months (with the lowest average wind speed) are July and August (4.5mph).
Average humidity in September
Saint Thomas, PA
- Average humidity in September: 78%
The months with the highest relative humidity are February, May, October and December (79%).
The months with the lowest relative humidity are April and July (75%).
Average rainfall in September
Saint Thomas, PA
- Average rainfall in September: 1.97"
The wettest month (with the highest rainfall) is May (3.15").
The driest month (with the least rainfall) is January (1.85").
Average rainfall days in September
Saint Thomas, PA
- Average rainfall days in September: 14.1 days
The month with the highest number of rainy days is May (18.8 days).
The month with the least rainy days is November (9 days).
Average snowfall in September
Saint Thomas, PA
- Average snowfall in September: 0"
The month with the highest snowfall is January (4.53").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in September
Saint Thomas, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (8.1 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
Saint Thomas, 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 36min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).
Average sunshine days in September
Saint Thomas, PA
- Average sunshine days in September: 14.4 days
The month with the most sunshine days is November (18.5 days).
The month with the least sunshine days is May (10.4 days).
Average UV index in September
Saint Thomas, PA
- Average UV index in September: 4
The months with the highest UV index are May, June and July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Saint Thomas, PA
- Average cloud cover in September: 38
The months with the most cloud cover are January, February and December (Cloud cover 50).
The month with the least cloud cover is July (Cloud cover 32).
Average visibility in September
Saint Thomas, PA
- Average visibility in September: 5mi
The months with the highest visibility are April, June, July, August and November (6mi).
The months with the lowest visibility are January, February, March, May, September, October and December (5mi).
