September weather forecast
Runnymeade Summit, MD

Share

Weather in September

The first month of the autumn, September, is still a warm month in Runnymeade Summit, Maryland, with an average temperature fluctuating between 56.7°F (13.7°C) and 75.2°F (24°C).

Temperature

During the shift to September, Runnymeade Summit records a mild decrease in average high-temperature, moving from 81.9°F (27.7°C) in August to a still moderately hot 75.2°F (24°C). The average low-temperature during September nights is a refreshing 56.7°F (13.7°C).

Humidity

In Runnymeade Summit, the average relative humidity in September is 79%.

Rainfall

In September, the rain falls for 14.5 days. Throughout September, 2.13" (54mm) of precipitation is accumulated. Throughout the year, in Runnymeade Summit, there are 157.5 rainfall days, and 27.52" (699mm) of precipitation is accumulated.

Snowfall

June through September are months without snowfall.

Daylight

The average length of the day in September is 12h and 26min.
On the first day of the month, sunrise is at 6:37 am and sunset at 7:39 pm. On the last day of September, sunrise is at 7:04 am and sunset at 6:51 pm EDT.

Sunshine

In Runnymeade Summit, the average sunshine in September is 8.9h.

UV index

The average daily maximum UV index in September is 4. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for the ordinary person.
Note: In September, the maximum UV index of 4 translates into these guidelines:
Ensure safety - Imperative it is to shield skin and eyes from damage. Direct exposure to the Sun during its peak hours around mid-day should be minimized for safety. Opt for tightly woven and loose clothing to enhance protection from the Sun.
Updated: Aug 15, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the usual temperature for Runnymeade Summit in September?

In September, in Runnymeade Summit, the average high-temperature is 75.2°F (24°C), and the average low-temperature is 56.7°F (13.7°C). The average heat index (a.k.a. 'feels like', 'felt air temperature'), which factors the actual air temperature with the relative humidity, in August is computed to be 87.8°F (31°C).

What is the average humidity in September?

In Runnymeade Summit, the average relative humidity in September is 79%.

How much does it rain in September?

In Runnymeade Summit, during September, the rain falls for 14.5 days and regularly aggregates up to 2.13" (54mm) of precipitation.

When it does not snow?

June through September are months without snowfall.

Does it snow in September?

In Runnymeade Summit, in September, it doesn't snow. In October, it regularly snows.

What is the average length of the day in September?

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

When are sunrise and sunset in September?

On the first day of September, sunrise is at 6:37 am and sunset at 7:39 pm. On the last day of the month, sunrise is at 7:04 am and sunset at 6:51 pm EDT.

How long on average sun shines in September?

The average sunshine duration in September is 8.9h.

How high is the UV index in September in Runnymeade Summit?

In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a medium hazard to health from unprotected exposure to UV radiation.
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
Runnymeade Summit, MD

Average temperature in September - Runnymeade Summit, MD
  • Average high temperature in September: 75.2°F

The warmest month (with the highest average high temperature) is July (84°F).
The month with the lowest average high temperature is January (36.7°F).

  • Average low temperature in September: 56.7°F

The month with the highest average low temperature is July (64.6°F).
The coldest month (with the lowest average low temperature) is January (23.5°F).

Average pressure in September
Runnymeade Summit, MD

Average pressure in September - Runnymeade Summit, MD
  • 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
Runnymeade Summit, MD

Average wind speed in September - Runnymeade Summit, MD
  • Average wind speed in September: 5.7mph

The windiest month (with the highest average wind speed) is March (8.4mph).
The calmest months (with the lowest average wind speed) are July and August (5mph).

Average humidity in September
Runnymeade Summit, MD

Average humidity in September - Runnymeade Summit, MD
  • Average humidity in September: 79%

The month with the highest relative humidity is May (80%).
The month with the lowest relative humidity is April (75%).

Average rainfall in September
Runnymeade Summit, MD

Average rainfall in September - Runnymeade Summit, MD
  • Average rainfall in September: 2.13"

The wettest month (with the highest rainfall) is August (3.23").
The driest month (with the least rainfall) is February (1.61").

Average rainfall days in September
Runnymeade Summit, MD

Average rainfall days in September - Runnymeade Summit, MD
  • Average rainfall days in September: 14.5 days

The month with the highest number of rainy days is May (18 days).
The month with the least rainy days is January (7.6 days).

Average snowfall in September
Runnymeade Summit, MD

Average snowfall in September - Runnymeade Summit, MD
  • Average snowfall in September: 0"

The month with the highest snowfall is March (3.03").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in September
Runnymeade Summit, MD

Average snowfall days in September - Runnymeade Summit, MD
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is January (6.7 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in September /
Average sunshine in September
Runnymeade Summit, MD

Average daylight in September / Average sunshine in September - Runnymeade Summit, MD
  • 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 5min

The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is February (Average sunshine: 4h and 42min).

Average sunshine days in September
Runnymeade Summit, MD

Average sunshine days in September - Runnymeade Summit, MD
  • Average sunshine days in September: 13.9 days

The month with the most sunshine days is November (19.2 days).
The month with the least sunshine days is May (10.8 days).

Average UV index in September
Runnymeade Summit, MD

Average UV index in September - Runnymeade Summit, MD
  • 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, November and December (UV index 2).

Average cloud cover in September
Runnymeade Summit, MD

Average cloud cover in September - Runnymeade Summit, MD
  • Average cloud cover in September: 37

The months with the most cloud cover are February and March (Cloud cover 48).
The month with the least cloud cover is July (Cloud cover 31).

Average visibility in September
Runnymeade Summit, MD

Average visibility in September - Runnymeade Summit, MD
  • 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).

Runnymeade Summit, Maryland, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location