Climate Overview
The climate in Ketchikan Harbor Seaplane Base is cool. The average annual temperature is 8°C and approximately 3245mm of precipitation falls per year. Ketchikan Harbor Seaplane Base receives a notable amount of rainfall throughout the year, including during its driest month. Ketchikan Harbor Seaplane Base is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: August, July, September. The coldest months are February, January, December, when temperatures can drop to 1°C. Snowfall occurs from January to December, with around 179cm accumulating over the season.
Temperature
Ketchikan Harbor Seaplane Base sees moderate temperature variation throughout the year, ranging from 1°C to 16°C. August is the warmest month, though highs remain moderate at 16°C with a mean of 15°C. February is the coolest month, with minimum temperatures around 1°C and an average of 2°C. Daily temperature variation is modest, with an average difference of 3°C between highs and lows. The sharpest temperature change occurs between September and October, with a 4°C shift in average temperatures.
Precipitation
Ketchikan Harbor Seaplane Base is a very wet location, receiving approximately 3245mm of precipitation annually, which averages out to around 270mm per month. The wettest month is November, averaging 437mm of rainfall. December and January also tend to see above-average precipitation. The driest month is May, with just 164mm. That's 273mm less than November, the wettest month. Precipitation varies noticeably between seasons, with the second half (July to December) of the year generally seeing more rainfall. Snowfall is a regular feature from January to December, with around 179cm accumulating over the season. March typically sees the most snow at around 46cm.
Wind
Ketchikan Harbor Seaplane Base is relatively calm, with an average annual wind speed of 5km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is January, averaging 6km/h, though still comfortable for most outdoor activities. The calmest conditions occur in July, with average winds dropping to 4km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 2km/h gap between the calmest and windiest months.
Seasons
94 days until Autumn
It is currently summer in Ketchikan Harbor Seaplane Base, which began on June 21, 2026. Ketchikan Harbor Seaplane Base is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in August at around 16°C, while the coldest stretch bottoms out in February near 1°C. Autumn is next, beginning on September 23, 2026 — 94 days from now.
Spring
Temperatures range from 3 to 12°C. Rainfall is heavy, totalling around 604mm across the season with a monthly average of 201mm. Winds are generally light, averaging 5km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 11 to 16°C. Rainfall is heavy, totalling around 698mm across the season with a monthly average of 233mm. Winds are generally light, averaging 4km/h. Comfortable clothing with a light layer for cooler evenings is all you need.
Autumn
Temperatures range from 5 to 14°C. Rainfall is heavy, totalling around 995mm across the season with a monthly average of 332mm. Expect around 14cm of snow accumulation during this period. Winds are generally light, averaging 5km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 1 to 4°C. Rainfall is heavy, totalling around 948mm across the season with a monthly average of 316mm. Expect around 113cm of snow accumulation during this period. Winds are generally light, averaging 6km/h. Warm winter clothing and waterproof boots are a must, and travel may be affected by snow.
Monthly Climate Data
The table below shows monthly climate averages for Ketchikan Harbor Seaplane Base based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Snow is measured in centimetres (cm) and reflects average monthly snowfall accumulation. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.
