September weather forecast
Marblemount, WA

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Weather in September

The first month of the autumn, September, is still a refreshing month in Marblemount, Washington, with an average temperature ranging between min 39.7°F (4.3°C) and max 62.8°F (17.1°C).

Temperature

The start of September signals a gentle decrease in the average high-temperature, transitioning from a pleasant 71.2°F (21.8°C) in August to a refreshing 62.8°F (17.1°C). Marblemount's nighttime temperatures in September reflect a stark contrast to the day's highs, falling to an average low of 39.7°F (4.3°C).

Humidity

The average relative humidity in September in Marblemount is 75%.

Rainfall

In Marblemount, Washington, during September, the rain falls for 14 days and regularly aggregates up to 2.4" (61mm) of precipitation. In Marblemount, Washington, during the entire year, the rain falls for 124 days and collects up to 55.28" (1404mm) of precipitation.

Snowfall

Months with snowfall are January through June, September through December. September is the first month it typically snows in Marblemount. Throughout September, in the average 1.4 snowfall days, it receives 1.3" (33mm) of snow. In Marblemount, during the entire year, snow falls for 142 days and aggregates up to 321.93" (8177mm) of snow.

Daylight

The average length of the day in September is 12h and 34min.
On the first day of September in Marblemount, sunrise is at 6:24 am and sunset at 7:46 pm. On the last day of the month, sunrise is at 7:05 am and sunset at 6:45 pm PDT.

Sunshine

The average sunshine in September is 9.1h.

UV index

The average daily maximum UV index in September is 2. A UV Index of 2, and less, symbolizes a low threat to health from unprotected exposure to Sun's UV rays for the average person.
Note: In September, the maximum UV index of 2 suggests these recommendations:
Those with sensitive skin, infants, and children require constant safeguarding from prolonged sun exposure. To protect against the Sun's most potent rays, avoid direct exposure around midday. To cut down UV radiation exposure by about half, sport a wide-brim hat. Guard yourself! Snow reflection can almost double the UV radiation from the Sun.
Updated: Feb 14, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are September temperatures in Marblemount?

In Marblemount, 62.8°F (17.1°C) is the average high-temperature and 39.7°F (4.3°C) is the average low-temperature during September.

What is the average humidity in September in Marblemount?

In Marblemount, Washington, the average relative humidity in September is 75%.

How many days does it rain in September in Marblemount?

In Marblemount, in September, during 14 rainfall days, 2.4" (61mm) of precipitation is typically accumulated.

When does it start snowing in Marblemount?

September is the first month it typically snows in Marblemount. Throughout September, in the average 1.4 snowfall days, it receives 1.3" (33mm) of snow.

What is the average length of the day in September in Marblemount?

In September, the average day length is 12h and 34min.

When are sunrise and sunset in September in Marblemount?

In September, on the first day of the month, sunrise is at 6:24 am and sunset at 7:46 pm. On the last day of the month, in Marblemount, sunrise is at 7:05 am and sunset at 6:45 pm PDT.

How long on average sun shines in September in Marblemount?

In Marblemount, the average sunshine duration in September is 9.1h.

How high is the UV index in September in Marblemount?

The average daily maximum UV index in September in Marblemount, Washington, is 2. A UV Index reading of 2, and below, represents a low health threat from unprotected exposure to UV radiation.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Marblemount, WA

Average temperature in September - Marblemount, WA
  • Average high temperature in September: 62.8°F

The warmest month (with the highest average high temperature) is August (71.2°F).
The month with the lowest average high temperature is December (30.7°F).

  • Average low temperature in September: 39.7°F

The month with the highest average low temperature is August (43.7°F).
The coldest month (with the lowest average low temperature) is December (19.6°F).

Average pressure in September
Marblemount, WA

Average pressure in September - Marblemount, WA
  • Average pressure in September: 30"Hg

The month with the highest atmospheric pressure is January (30.12"Hg).
The months with the lowest atmospheric pressure are June and August (29.98"Hg).

Average wind speed in September
Marblemount, WA

Average wind speed in September - Marblemount, WA
  • Average wind speed in September: 3.4mph

The windiest month (with the highest average wind speed) is January (4.7mph).
The calmest month (with the lowest average wind speed) is August (3.3mph).

Average humidity in September
Marblemount, WA

Average humidity in September - Marblemount, WA
  • Average humidity in September: 75%

The months with the highest relative humidity are January, February and March (91%).
The months with the lowest relative humidity are July and August (71%).

Average rainfall in September
Marblemount, WA

Average rainfall in September - Marblemount, WA
  • Average rainfall in September: 2.4"

The wettest month (with the highest rainfall) is January (9.25").
The driest month (with the least rainfall) is August (0.87").

Average rainfall days in September
Marblemount, WA

Average rainfall days in September - Marblemount, WA
  • Average rainfall days in September: 14 days

The month with the highest number of rainy days is June (17.5 days).
The month with the least rainy days is February (3.8 days).

Average snowfall in September
Marblemount, WA

Average snowfall in September - Marblemount, WA
  • Average snowfall in September: 1.3"

The month with the highest snowfall is January (71.57").
The months with the least snowfall are July and August (0").

Average snowfall days in September
Marblemount, WA

Average snowfall days in September - Marblemount, WA
  • Average snowfall days in September: 1.4 days

The month with the highest number of snowfall days is March (22.8 days).
The month with the least snowfall days is August (0 days).

Average daylight in September /
Average sunshine in September
Marblemount, WA

Average daylight in September / Average sunshine in September - Marblemount, WA
  • Average daylight in September: 12h and 4min

The month with the longest days is June (Average daylight: 16h and 6min).
The month with the shortest days is December (Average daylight: 8h and 24min).

  • Average sunshine in September: 9h and 1min

The month with the most sunshine is August (Average sunshine: 10h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).

Average sunshine days in September
Marblemount, WA

Average sunshine days in September - Marblemount, WA
  • Average sunshine days in September: 13.1 days

The month with the most sunshine days is August (18.1 days).
The month with the least sunshine days is April (6.5 days).

Average UV index in September
Marblemount, WA

Average UV index in September - Marblemount, WA
  • Average UV index in September: 2

The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, October and November (UV index 1).

Average cloud cover in September
Marblemount, WA

Average cloud cover in September - Marblemount, WA
  • Average cloud cover in September: 39

The month with the most cloud cover is March (Cloud cover 63).
The month with the least cloud cover is August (Cloud cover 30).

Average visibility in September
Marblemount, WA

Average visibility in September - Marblemount, WA
  • Average visibility in September: 5mi

The months with the highest visibility are June, July, August and September (5mi).
The months with the lowest visibility are January and March (3mi).

Marblemount, Washington, USA

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