September weather forecast and climate
Anchorage, AK

Wintertime in Anchorage, Alaska with mountains blanketed in snow
Wintertime in Anchorage, Alaska with mountains blanketed in snow
The first month of the autumn, September, is also a fresh month in Anchorage, Alaska, with average temperature varying between 52.7°F (11.5°C) and 43.9°F (6.6°C).

Temperature

In Anchorage, Alaska, the average high-temperature in September slightly decreases, from a mild 59.5°F (15.3°C) in August, to a cool 52.7°F (11.5°C). The average low-temperature, in September, is 43.9°F (6.6°C).

Humidity

In Anchorage, the average relative humidity in September is 78%.

Rainfall

The month with the most rainfall is September when the rain falls for 16 days and typically aggregates up to 1.93" (49mm) of precipitation.

Snowfall

Months with snowfall are January through May, September through December. September is the first month it typically snows in Anchorage. Throughout September, in the average 0.3 snowfall days, it receives 0.08" (2mm) of snow. Throughout the year, in Anchorage, there are 59.3 snowfall days, and 23.5" (597mm) of snow is accumulated.

Ocean temperature

In Anchorage, Alaska, the average water temperature is 51.6°F (10.9°C).
Note: Swimming in 51.6°F (10.9°C) is considered dangerous. Unprotected immersion in temperatures below 50°F (10°C) causes quickly maximum intensity cold shock with hyperventilation.

Daylight

The average length of the day in September is 12.8h.

Sunshine

In Anchorage, the average sunshine is 7.6h.

UV index

In September, the average daily maximum UV index is 2. A UV Index of 2, and less, symbolizes a low health risk from unprotected exposure to the Sun's UV rays for ordinary individuals.
Note: The average daily UV index of 2 in September transform into the following instructions:
Most people can stay in the Sun for up to 1 hour without burning, apart from children that always must be protected from sun exposure. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.

What is the temperature in September in Anchorage?

In September, the average high-temperature is 52.7°F (11.5°C), and the average low-temperature is 43.9°F (6.6°C).

What is the average humidity in September in Anchorage?

The average relative humidity in September in Anchorage, Alaska, is 78%.

How much does it rain in Anchorage in September?

In Anchorage, in September, it is raining for 16 days, with typically 1.93" (49mm) of accumulated precipitation.

What is the wettest month in Anchorage?

The month with the most rainfall in Anchorage is September when the rain falls for 16 days and typically aggregates up to 1.93" (49mm) of precipitation.

When does it start to snow in Anchorage?

September is the first month it typically snows. Throughout September, in the average 0.3 snowfall days, it receives 0.08" (2mm) of snow.

How cold is the water in September in Anchorage?

In Anchorage, Alaska, in September, the average water temperature is 51.6°F (10.9°C). Swimming in 51.6°F (10.9°C) is considered life-threatening. Even a few minutes in 55.4°F (13°C) water is uncomfortable, and swimming below 50°F (10°C) may cause total loss of breathing control and cold shock, depending on a person's physique.

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

In Anchorage, Alaska, the average length of the day in September is 12.8h.

How many hours of sunshine does Anchorage have in September?

In Anchorage, the average sunshine in September is 7.6h.

What is the UV index intensity in September in Anchorage?

In September, the average daily maximum UV index in Anchorage is 2. A UV Index of 2, and less, symbolizes a low health risk from the exposure to the Sun's UV rays.
Average temperature in September - Anchorage, AK
  • Average high temperature in September: 52.7°F

The warmest month (with the highest average high temperature) is July (61.9°F).
The month with the lowest average high temperature is January (20.3°F).

  • Average low temperature in September: 43.9°F

The month with the highest average low temperature is July (51.3°F).
The coldest month (with the lowest average low temperature) is January (13.1°F).

Average pressure in September - Anchorage, AK
  • Average pressure in September: 29.74"

The month with the highest atmospheric pressure is July (29.96").
Months with the lowest atmospheric pressure are November and December (29.67").

Average wind speed in September - Anchorage, AK
  • Average wind speed in September: 5.2mph

The windiest month (with the highest average wind speed) is November (6.3mph).
The calmest month (with the lowest average wind speed) is July (4.5mph).

Average humidity in September - Anchorage, AK
  • Average humidity in September: 78%

Months with the highest relative humidity are January, February and March (86%).
The month with the lowest relative humidity is May (68%).

Average rainfall in September - Anchorage, AK
  • Average rainfall in September: 1.93"

The wettest month (with the highest rainfall) is September (1.93").
The driest month (with the least rainfall) is May (0.55").

Average rainfall days in September - Anchorage, AK
  • Average rainfall days in September: 16 days

The month with the highest number of rainy days is August (17.9 days).
The month with the least rainy days is February (7 days).

Average snowfall in September - Anchorage, AK
  • Average snowfall in September: 0.08"

The month with the highest snowfall is December (5.51").
Months with the least snowfall are June, July and August (0").

Average snowfall days in September - Anchorage, AK
  • Average snowfall days in September: 0.3 days

The month with the highest number of snowfall days is December (11.6 days).
Months with the least snowfall days are June, July and August (0 days).

Average sea temperature in September - Anchorage, AK
  • Average sea temperature in September: 51.6°F

The best month for swimming (with the highest average sea temperature) is August (53.1°F).
The coldest month (with the lowest average sea temperature) is February (35.8°F).

Average daylight in September / Average sunshine in September - Anchorage, AK
  • Average daylight in September: 12.8h

The month with the longest days is June (Average daylight: 19.2h).
The month with the shortest days is December (Average daylight: 5.6h).

  • Average sunshine in September: 7.6h

Months with the most sunshine are May and June (Average sunshine: 11.7h).
The month with the least sunshine is December (Average sunshine: 3.8h).

Average sunshine days in September - Anchorage, AK
  • Average sunshine days in September: 11.1 days

The month with the most sunshine days is January (16.9 days).
The month with the least sunshine days is September (11.1 days).

Average UV index in September - Anchorage, AK
  • Average UV index in September: 2

Months with the highest UV index are June and July (UV index 4).
The month with the lowest UV index is February (UV index 1).

Average cloud cover in September - Anchorage, AK
  • Average cloud cover in September: 44

The month with the most cloud cover is December (Cloud cover 47).
The month with the least cloud cover is May (Cloud cover 38).

Average visibility in September - Anchorage, AK
  • Average visibility in September: 6mi

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