September weather forecast
Saint Mary's, AK

Share

Weather in September

September, the first month of the autumn in Saint Mary's, is also a fresh month, with an average temperature fluctuating between 40.1°F (4.5°C) and 51.1°F (10.6°C).

Temperature

Saint Mary's's weather in September involves a mild decrease in the average high-temperature, moving down slightly from August's refreshing 59°F (15°C) to a cool 51.1°F (10.6°C). An average nighttime temperature of 40.1°F (4.5°C) is noted in Saint Mary's during the month of September.

Humidity

In September, the average relative humidity in Saint Mary's is 81%.

Rainfall

In Saint Mary's, Alaska, during September, the rain falls for 14.5 days and regularly aggregates up to 1.77" (45mm) of precipitation. In Saint Mary's, during the entire year, the rain falls for 104.5 days and collects up to 15.75" (400mm) of precipitation.

Snowfall

January through May, September through December are months with snowfall. September is the first month it typically snows. Throughout September, in the average 0.8 snowfall days, it receives 0.12" (3mm) of snow. Throughout the year, in Saint Mary's, there are 71.4 snowfall days, and 22.72" (577mm) of snow is accumulated.

Daylight

The average length of the day in September in Saint Mary's is 12h and 53min.
On the first day of the month, sunrise is at 7:44 am and sunset at 9:59 pm. On the last day of September, in Saint Mary's, sunrise is at 8:59 am and sunset at 8:24 pm AKDT.

Sunshine

In September, the average sunshine in Saint Mary's, Alaska, is 4.5h.

UV index

The average daily maximum UV index in September is 2. A UV Index value of 2, and less, symbolizes a low health risk from exposure to the Sun's UV rays for ordinary individuals.
Note: An average UV index of 2 in September transforms into this advice:
Children necessitate constant protection from sunlight, unlike the majority, who can remain under the sun for about an hour without burning. When the Sun's UV radiation is most intense during midday, it's best to find shade and limit exposure. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Keep in mind! Snow's reflective quality can nearly double the intensity of the Sun's UV radiation.
[Resources]

Frequently asked questions

What is the temperature in September in Saint Mary's?

In September, the average high-temperature and low-temperature in Saint Mary's are 51.1°F (10.6°C) and 40.1°F (4.5°C) respectively.

What is the average humidity in September in Saint Mary's?

In Saint Mary's, the average relative humidity in September is 81%.

How much does it rain in Saint Mary's in September?

In September, the rain falls for 14.5 days. Throughout September, 1.77" (45mm) of precipitation is accumulated.

When does it start snowing in Saint Mary's?

September is the first month it typically snows in Saint Mary's, Alaska. Throughout September, in the average 0.8 snowfall days, it receives 0.12" (3mm) of snow.

What is the average length of the day in September in Saint Mary's?

The average day length in September in Saint Mary's, Alaska, is 12h and 53min.

What time are sunrise and sunset in September in Saint Mary's?

On the first day of September in Saint Mary's, Alaska, sunrise is at 7:44 am and sunset at 9:59 pm. On the last day of the month, sunrise is at 8:59 am and sunset at 8:24 pm AKDT.

How many hours of sunshine does Saint Mary's have in September?

The average sunshine duration in September in Saint Mary's is 4.5h.

What is the UV index intensity in September in Saint Mary's?

In Saint Mary's, Alaska, the average daily maximum UV index in September is 2. A UV Index estimate of 2, and below, represents a low health risk from exposure to the Sun's 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
Saint Mary's, AK

Average temperature in September - Saint Mary
  • Average high temperature in September: 51.1°F

The warmest month (with the highest average high temperature) is July (61.5°F).
The month with the lowest average high temperature is January (11.3°F).

  • Average low temperature in September: 40.1°F

The month with the highest average low temperature is July (47.5°F).
The coldest month (with the lowest average low temperature) is January (2.3°F).

[Resources]

Average pressure in September
Saint Mary's, AK

Average pressure in September - Saint Mary
  • Average pressure in September: 29.72"Hg

The month with the highest atmospheric pressure is July (29.91"Hg).
The months with the lowest atmospheric pressure are October and December (29.67"Hg).

[Resources]

Average wind speed in September
Saint Mary's, AK

Average wind speed in September - Saint Mary
  • Average wind speed in September: 10.2mph

The windiest month (with the highest average wind speed) is February (11.9mph).
The calmest month (with the lowest average wind speed) is July (8.9mph).

[Resources]

Average humidity in September
Saint Mary's, AK

Average humidity in September - Saint Mary
  • Average humidity in September: 81%

The months with the highest relative humidity are January, February, March and December (91%).
The month with the lowest relative humidity is June (66%).

[Resources]

Average rainfall in September
Saint Mary's, AK

Average rainfall in September - Saint Mary
  • Average rainfall in September: 1.77"

The wettest month (with the highest rainfall) is August (2.13").
The driest months (with the least rainfall) are January and June (0.87").

[Resources]

Average rainfall days in September
Saint Mary's, AK

Average rainfall days in September - Saint Mary
  • Average rainfall days in September: 14.5 days

The month with the highest number of rainy days is August (17.8 days).
The months with the least rainy days are January and February (2.4 days).

[Resources]

Average snowfall in September
Saint Mary's, AK

Average snowfall in September - Saint Mary
  • Average snowfall in September: 0.12"

The month with the highest snowfall is February (5.28").
The months with the least snowfall are June, July and August (0").

[Resources]

Average snowfall days in September
Saint Mary's, AK

Average snowfall days in September - Saint Mary
  • Average snowfall days in September: 0.8 days

The month with the highest number of snowfall days is February (11.4 days).
The months with the least snowfall days are July and August (0 days).

[Resources]

Average daylight in September /
Average sunshine in September
Saint Mary's, AK

Average daylight in September / Average sunshine in September - Saint Mary
  • Average daylight in September: 12h and 5min

The month with the longest days is June (Average daylight: 19h and 36min).
The month with the shortest days is December (Average daylight: 5h and 18min).

  • Average sunshine in September: 4h and 3min

The month with the most sunshine is May (Average sunshine: 7h and 54min).
The month with the least sunshine is December (Average sunshine: 2h and 36min).

[Resources]

Average sunshine days in September
Saint Mary's, AK

Average sunshine days in September - Saint Mary
  • Average sunshine days in September: 12.4 days

The month with the most sunshine days is March (19.5 days).
The month with the least sunshine days is August (10.9 days).

[Resources]

Average UV index in September
Saint Mary's, AK

Average UV index in September - Saint Mary
  • Average UV index in September: 2

The months with the highest UV index are May, June, July and August (UV index 3).
The months with the lowest UV index are March, November and December (UV index 1).

[Resources]

Average cloud cover in September
Saint Mary's, AK

Average cloud cover in September - Saint Mary
  • Average cloud cover in September: 64

The month with the most cloud cover is July (Cloud cover 68).
The month with the least cloud cover is June (Cloud cover 54).

[Resources]

Average visibility in September
Saint Mary's, AK

Average visibility in September - Saint Mary
  • Average visibility in September: 6mi

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

[Resources]

Saint Mary's, Alaska, USA

Weather forecast for your location

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