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
The transition into September is accompanied by a slight temperature decrease, with the average high-temperature shifting from 81.9°F (27.7°C) in August to a still warm 74.8°F (23.8°C). In the month of September, Greencastle's average low-temperature falls to a moderate 55.6°F (13.1°C).Humidity
In September, the average relative humidity is 78%.Rainfall
In September, the rain falls for 14.1 days. Throughout September, 1.97" (50mm) of precipitation is accumulated. In Greencastle, during the entire year, the rain falls for 161.8 days and collects up to 28.07" (713mm) of precipitation.Snowfall
May through September are months without snowfall in Greencastle.Daylight
In Greencastle, 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 7:41 pm. On the last day of the month, sunrise is at 7:06 am and sunset at 6:54 pm EDT.
Sunshine
In September, the average sunshine is 8.6h.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 average individuals.Note: The average daily UV index of 4 in September transforms into the following instructions:
Take precautions - Protection against sunburn is recommended. The mid-day Sun emits the most powerful UV radiation, so seek shade and minimize exposure. Employ a wide-brim hat for potent defense against up to 50% of UV rays.
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Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in September?
What is the average humidity in September?
How much does it rain in Greencastle in September?
When it does not snow?
Does it snow in September?
How many hours of daylight does Greencastle have in September?
When are sunrise and sunset in September in Greencastle?
How long on average sun shines in September?
What is the UV index reading in September?
Average temperature in September
Greencastle, 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
Greencastle, 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
Greencastle, 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
Greencastle, 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
Greencastle, 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
Greencastle, 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
Greencastle, 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
Greencastle, 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
Greencastle, PA
- Average daylight in September: 12h and 2min
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 4min
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
Greencastle, 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
Greencastle, 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
Greencastle, 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
Greencastle, 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).
Greencastle, Pennsylvania, USA
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