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 arrival of September is marked by a minor reduction in average high-temperature, sliding from 84.2°F (29°C) in August to a still moderately hot 77°F (25°C). Cornwell in September anticipates an average nighttime temperature of 60.3°F (15.7°C).Humidity
In Cornwell, the average relative humidity in September is 74%.Rainfall
In Cornwell, in September, it is raining for 12.8 days, with typically 2.01" (51mm) of accumulated precipitation. Throughout the year, there are 153.8 rainfall days, and 30.94" (786mm) of precipitation is accumulated.Snowfall
In Cornwell, snow does not fall in June through October.Daylight
In September, the average length of the day in Cornwell 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, in Cornwell, sunrise is at 6:55 am and sunset at 6:43 pm EDT.
Sunshine
The average sunshine in September in Cornwell is 8.6h.UV index
In September, the average daily maximum UV index in Cornwell, Pennsylvania, is 5. A UV Index reading of 3 to 5 represents a moderate threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: A maximum high UV index of 5 in September translates into the following recommendations:
Prioritize safety - Suggestions to prevent sun damage are offered. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. Shield yourself from the harmful effects of UV radiation with sun-protective attire, a hat, and quality sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in Cornwell in September?
What is the average humidity in September in Cornwell?
How many days does it rain in September in Cornwell?
When it does not snow in Cornwell?
What is the average length of the day in September in Cornwell?
When is the sunrise / sunset in September in Cornwell?
How long on average sun shines in September in Cornwell?
How high is the UV index in September in Cornwell?
Average temperature in September
Cornwell, PA
- Average high temperature in September: 77°F
The warmest month (with the highest average high temperature) is July (86.4°F).
The month with the lowest average high temperature is January (37.4°F).
- Average low temperature in September: 60.3°F
The month with the highest average low temperature is July (68.9°F).
The coldest month (with the lowest average low temperature) is January (25.2°F).
Average pressure in September
Cornwell, 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 (29.93"Hg).
Average wind speed in September
Cornwell, PA
- Average wind speed in September: 6mph
The windiest months (with the highest average wind speed) are March and April (8.5mph).
The calmest month (with the lowest average wind speed) is August (5.6mph).
Average humidity in September
Cornwell, PA
- Average humidity in September: 74%
The months with the highest relative humidity are February and October (77%).
The months with the lowest relative humidity are April, July and August (71%).
Average rainfall in September
Cornwell, PA
- Average rainfall in September: 2.01"
The wettest month (with the highest rainfall) is July (3.39").
The driest month (with the least rainfall) is January (1.89").
Average rainfall days in September
Cornwell, PA
- Average rainfall days in September: 12.8 days
The month with the highest number of rainy days is July (18.5 days).
The month with the least rainy days is November (7.5 days).
Average snowfall in September
Cornwell, PA
- Average snowfall in September: 0"
The month with the highest snowfall is March (2.76").
The months with the least snowfall are June, July, August, September and October (0").
Average snowfall days in September
Cornwell, PA
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (5.2 days).
The months with the least snowfall days are June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Cornwell, PA
- Average daylight in September: 12h and 2min
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 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 42min).
Average sunshine days in September
Cornwell, PA
- Average sunshine days in September: 15.2 days
The month with the most sunshine days is November (21.2 days).
The month with the least sunshine days is July (10.4 days).
Average UV index in September
Cornwell, 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
Cornwell, PA
- Average cloud cover in September: 39
The month with the most cloud cover is February (Cloud cover 48).
The month with the least cloud cover is July (Cloud cover 33).
Average visibility in September
Cornwell, 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).
Cornwell, Pennsylvania, USA
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