September weather forecast
Coatesville, PA

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Weather in September

September in Coatesville signifies an initiation of cooler climate, transitioning from the warmth of summer to the early chills of fall. A considerable drop in temperature from 81.1°F (27.3°C) in August reflects the advent of autumn. With the upcoming October, a further dip in temperature mirrors the arrival of the colder season. September carries a balanced mix of warm but comfortable daytime temperatures with cool evenings aiding the city in adjusting to the changing season. It is identified as the month where fall starts to tiptoe into the daily weather reports.

Temperature

With the arrival of September, Coatesville experiences a modest decline in average high-temperatures, transitioning from a warm 81.1°F (27.3°C) in August to a still moderately hot 74.8°F (23.8°C). Throughout September, the temperature tends to fall to a consistent average low of 57.4°F (14.1°C).

Humidity

The average relative humidity in September is 80%.

Rainfall

In Coatesville, in September, it is raining for 11.5 days, with typically 1.38" (35mm) of accumulated precipitation. Throughout the year, there are 138.3 rainfall days, and 19.76" (502mm) of precipitation is accumulated.

Snowfall

In Coatesville, snow does not fall in June through September.

Daylight

In Coatesville, the average length of the day in September is 12h and 26min.
On the first day of September, sunrise is at 6:31 am and sunset at 7:34 pm. On the last day of the month, sunrise is at 6:59 am and sunset at 6:46 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 value of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV radiation for ordinary individuals.
Note: In September, an average UV index of 4 transforms into the following instructions:
Be vigilant - Preventing sunburn is recommended. Direct Sun exposure should be minimized especially during midday when radiation is most intense. On days when the sun blazes, arm yourself with sunglasses that block UVA and UVB radiation.

Frequently asked questions

What are September temperatures?

In Coatesville, in September, the average high-temperature is 74.8°F (23.8°C), and the average low-temperature is 57.4°F (14.1°C). The average heat index (a.k.a. 'apparent temperature', 'real feel'), which represents the influence of relative humidity on air temperature, in August is computed to be 86°F (30°C).

What is the average humidity in September?

In September, the average relative humidity is 80%.

How many days does it rain in September?

In Coatesville, in September, it is raining for 11.5 days, with typically 1.38" (35mm) of accumulated precipitation.

When it does not snow?

June through September are months without snowfall.

Does it snow in September?

In Coatesville, Pennsylvania, in September, it doesn't snow. In October, it regularly snows.

How many hours of daylight does Coatesville have in September?

In September, the average day length is 12h and 26min.

When are sunrise and sunset in September in Coatesville?

In September, on the first day of the month, sunrise is at 6:31 am and sunset at 7:34 pm. On the last day of the month, sunrise is at 6:59 am and sunset at 6:46 pm EDT.

How many hours of sunshine does Coatesville have in September?

In September, the average sunshine duration is 8.6h.

What is the UV index reading in September?

In Coatesville, the average daily maximum UV index in September is 4. A UV Index estimate of 3 to 5 represents a medium health risk from exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Coatesville, PA

Average temperature in September - Coatesville, PA
  • Average high temperature in September: 74.8°F

The warmest month (with the highest average high temperature) is July (83.5°F).
The month with the lowest average high temperature is January (35.6°F).

  • Average low temperature in September: 57.4°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 (23.4°F).

Average pressure in September
Coatesville, PA

Average pressure in September - Coatesville, 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
Coatesville, PA

Average wind speed in September - Coatesville, PA
  • Average wind speed in September: 5.7mph

The windiest months (with the highest average wind speed) are January, February and March (8.8mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).

Average humidity in September
Coatesville, PA

Average humidity in September - Coatesville, PA
  • Average humidity in September: 80%

The months with the highest relative humidity are May and October (81%).
The month with the lowest relative humidity is April (76%).

Average rainfall in September
Coatesville, PA

Average rainfall in September - Coatesville, PA
  • Average rainfall in September: 1.38"

The wettest month (with the highest rainfall) is August (2.72").
The driest month (with the least rainfall) is February (1.14").

Average rainfall days in September
Coatesville, PA

Average rainfall days in September - Coatesville, PA
  • Average rainfall days in September: 11.5 days

The month with the highest number of rainy days is July (16.8 days).
The month with the least rainy days is January (6.4 days).

Average snowfall in September
Coatesville, PA

Average snowfall in September - Coatesville, PA
  • Average snowfall in September: 0"

The month with the highest snowfall is March (2.32").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in September
Coatesville, PA

Average snowfall days in September - Coatesville, PA
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (5.8 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in September /
Average sunshine in September
Coatesville, PA

Average daylight in September / Average sunshine in September - Coatesville, 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 24min).
The month with the least sunshine is February (Average sunshine: 4h and 30min).

Average sunshine days in September
Coatesville, PA

Average sunshine days in September - Coatesville, PA
  • Average sunshine days in September: 16.8 days

The month with the most sunshine days is November (20 days).
The month with the least sunshine days is July (12.4 days).

Average UV index in September
Coatesville, PA

Average UV index in September - Coatesville, 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, March, November and December (UV index 2).

Average cloud cover in September
Coatesville, PA

Average cloud cover in September - Coatesville, PA
  • Average cloud cover in September: 40

The month with the most cloud cover is February (Cloud cover 50).
The month with the least cloud cover is July (Cloud cover 33).

Average visibility in September
Coatesville, PA

Average visibility in September - Coatesville, 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).

Coatesville, Pennsylvania, USA

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