Ketchikan
Alaska, USA
Long-term weather forecast
Long-term weather forecast

September weather forecast and climate
Ketchikan, AK

Beautiful and colorful houses along the iconic waterfront boardwalk on Creek Street in Ketchikan, Alaska
Beautiful and colorful houses along the iconic waterfront boardwalk on Creek Street in Ketchikan, Alaska
September, the first month of the autumn, in Ketchikan, is still a mild month, with average temperature varying between 59.2°F (15.1°C) and 47.1°F (8.4°C).

Temperature

In Ketchikan, Alaska, the average high-temperature in September marginally drops, from a comfortable 64.6°F (18.1°C) in August, to a moderate 59.2°F (15.1°C). In September, the average low-temperature is 47.1°F (8.4°C).

Rainfall

In Ketchikan, Alaska, in September, during 19 rainfall days, 14.2" (361.2mm) of precipitation is typically accumulated. Throughout the year, in Ketchikan, Alaska, there are 229 rainfall days, and 153.2" (3892.3mm) of precipitation is accumulated.

Snowfall

June through September are months without snowfall.

Ocean temperature

In Ketchikan, the average seawater temperature in September is 53.2°F (11.8°C).
Note: Swimming in 53.2°F (11.8°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.

Daylight

In Ketchikan, the average length of the day is 12.7h.

Sunshine

In Ketchikan, Alaska, the average sunshine is 3h.

UV index

The average daily maximum UV index in September is 3. A UV Index reading of 3 to 5 represents a medium health hazard from the exposure to the Sun's UV radiation for the average person.
Note: In September, the average maximum UV index of 3 translate into the following recommendations:
Take precautions. Light skin individuals may get burned in less than 30 minutes. The Sun's most intense and consequently most harmful UV radiation during midday hours should be decreased by minimizing exposure and seeking shade. A wide-brim hat offers excellent sun protection for eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Tightly woven, loose-fitting clothes provide additional protection from the Sun.

What is the temperature in September in Ketchikan?

In Ketchikan, in September, the average high-temperature is 59.2°F (15.1°C), and the average low-temperature is 47.1°F (8.4°C).

How many days does it rain in September in Ketchikan?

In Ketchikan, Alaska, in September, it is raining for 19 days, with typically 14.2" (361.2mm) of accumulated precipitation.

Does it snow in Ketchikan in September?

In Ketchikan, Alaska, in September, it doesn't snow. In October, it regularly snows.

When it does not snow in Ketchikan?

In Ketchikan, Alaska, snow does not fall in June through September.

How cold is the water in September in Ketchikan?

In September, the average ocean temperature in Ketchikan is 53.2°F (11.8°C). Swimming in 53.2°F (11.8°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.

How many hours of daylight does Ketchikan have in September?

In Ketchikan, the average length of the day in September is 12.7h.

How long on average sun shines in September in Ketchikan?

In Ketchikan, Alaska, the average sunshine in September is 3h.

How high is the UV index in September in Ketchikan?

The average daily maximum UV index in September in Ketchikan is 3. A UV Index estimate of 3 to 5 represents a medium hazard to health from the exposure to the Sun's UV rays.
Average temperature in September - Ketchikan, AK
  • Average high temperature in September: 59.1°F

The warmest month (with the highest average high temperature) is August (64.5°F).
The month with the lowest average high temperature is January (38.4°F).

  • Average low temperature in September: 47.1°F

The month with the highest average low temperature is August (52.1°F).
The coldest month (with the lowest average low temperature) is January (28.8°F).

Average rainfall in September - Ketchikan, AK
  • Average rainfall in September: 14.2"

The wettest month (with the highest rainfall) is October (22.2").
Driest months (with the lowest rainfall) are June and July (7.4").

Average rainfall days in September - Ketchikan, AK
  • Average rainfall days in September: 19 days

The month with the highest number of rainy days is October (24 days).
The month with the lowest number of rainy days is July (15 days).

Average snowfall in September - Ketchikan, AK
  • Average snowfall in September: 0"

The month with the highest snowfall is January (13.3").
Months with the lowest snowfall are June, July, August and September (0").

Average sea temperature in September - Ketchikan, AK
  • Average sea temperature in September: 53.3°F

The best month for swimming (with the highest average sea temperature) is August (55.9°F).
The coldest month (with the lowest average sea temperature) is March (42.5°F).

Average daylight in September / Average sunshine in September - Ketchikan, AK
  • Average daylight in September: 12.7h

The month with the longest days is June (Average daylight: 17.4h).
The month with shortest days is December (Average daylight: 7.2h).

  • Average sunshine in September: 3h

The month with most sunshine is May (Average sunshine: 6h).
The month with least sunshine is December (Average sunshine: 1h).

Average UV index in September - Ketchikan, AK
  • Average UV index in September: 3

The month with the highest UV index is July (UV index 6).
Months with the lowest UV index are January and December (UV index 0).