September weather forecast
Grassmere Park, PA

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Weather in September

The first month of the autumn, September, is still a pleasant month in Grassmere Park, Pennsylvania, with an average temperature fluctuating between 52.2°F (11.2°C) and 72.5°F (22.5°C).

Temperature

A subtle change in temperatures is noted as August gives way to September, with average highs reducing from a moderately hot 78.6°F (25.9°C) to a pleasant 72.5°F (22.5°C). Grassmere Park's temperature lowers to a mean of 52.2°F (11.2°C) during the nights in September.

Humidity

In September, the average relative humidity is 80%.

Rainfall

The month with the least rainfall is September, when the rain falls for 12.8 days and typically collects 2.05" (52mm) of precipitation.

Snowfall

June through September are months without snowfall.

Daylight

In September, the average length of the day is 12h and 28min.
On the first day of September, sunrise is at 6:32 am and sunset at 7:37 pm. On the last day of the month, sunrise is at 7:01 am and sunset at 6:48 pm EDT.

Sunshine

In September, the average sunshine is 8.6h.

UV index

The average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a moderate health risk from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: An average maximum UV index of 4 in September leads to these recommendations:
Ensure safety - Imperative it is to shield skin and eyes from damage. Avoiding direct sunlight during midday hours helps reduce the risk from intense UV radiation. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage.
Updated: Jun 21, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are the temperatures in Grassmere Park in September?

The average high-temperature and low-temperature during September are 72.5°F (22.5°C) and 52.2°F (11.2°C) respectively. In July, the average heat index (a.k.a. 'felt air temperature', 'real feel'), which takes the relative humidity and factors it into the air temperature reading, is evaluated at 87.8°F (31°C).

What is the average humidity in September?

The average relative humidity in September is 80%.

What is the driest month in Grassmere Park?

The month with the least rainfall is September, when the rain falls for 12.8 days and typically collects 2.05" (52mm) of precipitation.

How much does it rain in September?

In Grassmere Park, in September, during 12.8 rainfall days, 2.05" (52mm) of precipitation is typically accumulated.

When it does not snow?

In Grassmere Park, snow does not fall in June through September.

Does it snow in September?

In Grassmere Park, in September, it doesn't snow. In October, it regularly snows.

How many hours of daylight does Grassmere Park have in September?

The average day length in September is 12h and 28min.

When is the sunrise / sunset in September?

On the first day of September, sunrise is at 6:32 am and sunset at 7:37 pm. On the last day of the month, sunrise is at 7:01 am and sunset at 6:48 pm EDT.

How long on average sun shines in September?

In Grassmere Park, the average sunshine duration in September is 8.6h.

How high is the UV index in September in Grassmere Park?

In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a moderate health threat from unsafe 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
Grassmere Park, PA

Average temperature in September - Grassmere Park, PA
  • Average high temperature in September: 72.5°F

The warmest month (with the highest average high temperature) is July (81.3°F).
The month with the lowest average high temperature is January (31.8°F).

  • Average low temperature in September: 52.2°F

The month with the highest average low temperature is July (59.5°F).
The coldest month (with the lowest average low temperature) is January (19°F).

Average pressure in September
Grassmere Park, PA

Average pressure in September - Grassmere Park, PA
  • Average pressure in September: 30.07"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
Grassmere Park, PA

Average wind speed in September - Grassmere Park, PA
  • Average wind speed in September: 5.5mph

The windiest months (with the highest average wind speed) are March and April (8.1mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).

Average humidity in September
Grassmere Park, PA

Average humidity in September - Grassmere Park, PA
  • Average humidity in September: 80%

The month with the highest relative humidity is February (83%).
The month with the lowest relative humidity is April (77%).

Average rainfall in September
Grassmere Park, PA

Average rainfall in September - Grassmere Park, PA
  • Average rainfall in September: 2.05"

The wettest months (with the highest rainfall) are April and May (2.99").
The driest month (with the least rainfall) is September (2.05").

Average rainfall days in September
Grassmere Park, PA

Average rainfall days in September - Grassmere Park, PA
  • Average rainfall days in September: 12.8 days

The month with the highest number of rainy days is May (17.8 days).
The month with the least rainy days is January (9.3 days).

Average snowfall in September
Grassmere Park, PA

Average snowfall in September - Grassmere Park, PA
  • Average snowfall in September: 0"

The month with the highest snowfall is January (5.94").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in September
Grassmere Park, PA

Average snowfall days in September - Grassmere Park, PA
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (12.9 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in September /
Average sunshine in September
Grassmere Park, PA

Average daylight in September / Average sunshine in September - Grassmere Park, PA
  • Average daylight in September: 12h and 3min

The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).

  • Average sunshine in September: 8h and 4min

The month with the most sunshine is July (Average sunshine: 10h and 12min).
The month with the least sunshine is February (Average sunshine: 3h and 48min).

Average sunshine days in September
Grassmere Park, PA

Average sunshine days in September - Grassmere Park, PA
  • Average sunshine days in September: 14.7 days

The month with the most sunshine days is November (16.3 days).
The month with the least sunshine days is February (9.8 days).

Average UV index in September
Grassmere Park, PA

Average UV index in September - Grassmere Park, PA
  • Average UV index in September: 4

The months with the highest UV index are May, June, July and August (UV index 5).
The month with the lowest UV index is December (UV index 1).

Average cloud cover in September
Grassmere Park, PA

Average cloud cover in September - Grassmere Park, PA
  • Average cloud cover in September: 40

The months with the most cloud cover are February and December (Cloud cover 58).
The month with the least cloud cover is July (Cloud cover 35).

Average visibility in September
Grassmere Park, PA

Average visibility in September - Grassmere Park, PA
  • Average visibility in September: 5mi

The month with the highest visibility is April (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October, November and December (5mi).

Grassmere Park, Pennsylvania, USA

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