Climate Overview
The climate in Juneau Harbor Seaplane Base is cool. The average annual temperature is 4°C and approximately 3006mm of precipitation falls per year. Juneau Harbor Seaplane Base receives a notable amount of rainfall throughout the year, including during its driest month. Juneau Harbor Seaplane Base is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: July, August, June. The coldest months are February, January, December, when temperatures can drop to -7°C. Juneau Harbor Seaplane Base experiences heavy snowfall, typically from January through December.
Temperature
Temperatures in Juneau Harbor Seaplane Base vary considerably across the year, with a 24°C difference between the coldest and warmest months. July is the warmest month, though highs remain moderate at 17°C with a mean of 14°C. The coldest month is February, when overnight lows fall to -7°C and the daily average is -5°C. Daily temperature variation is modest, with an average difference of 6°C between highs and lows. The sharpest temperature change occurs between September and October, with a 6°C shift in average temperatures.
Precipitation
Juneau Harbor Seaplane Base is a very wet location, receiving approximately 3006mm of precipitation annually, which averages out to around 251mm per month. The wettest month is December, averaging 381mm of rainfall. October and August also tend to see above-average precipitation. The driest month is March, with just 163mm. That's 218mm less than December, the wettest month. Rainfall is relatively evenly distributed throughout the year, so there is no pronounced dry or wet season to plan around. Juneau Harbor Seaplane Base receives heavy snowfall, accumulating around 1204cm annually from January through December. The snowiest month is December, with approximately 293cm. Winter travel should account for significant snow cover.
Wind
Juneau Harbor Seaplane Base is relatively calm, with an average annual wind speed of 2km/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 2km/h, though still comfortable for most outdoor activities. The calmest conditions occur in July, with average winds dropping to 1km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 1km/h gap between the calmest and windiest months.
Seasons
94 days until Autumn
It is currently summer in Juneau Harbor Seaplane Base, which began on June 21, 2026. Juneau 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 July at around 17°C, while the coldest stretch bottoms out in February near -7°C. Autumn is next, beginning on September 23, 2026 — 94 days from now.
Spring
Temperatures range from -4 to 12°C. Rainfall is heavy, totalling around 540mm across the season with a monthly average of 180mm. Winds are generally light, averaging 2km/h. An umbrella or waterproof jacket is advisable as spring showers are frequent.
Summer
Temperatures range from 8 to 17°C. Rainfall is heavy, totalling around 670mm across the season with a monthly average of 223mm. Winds are generally light, averaging 1km/h. Comfortable clothing with a light layer for cooler evenings is all you need.
Autumn
Temperatures range from -3 to 14°C. Rainfall is heavy, totalling around 903mm across the season with a monthly average of 301mm. Expect around 216cm of snow accumulation during this period. Winds are generally light, averaging 2km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from -7 to 0°C. Rainfall is heavy, totalling around 893mm across the season with a monthly average of 298mm. Expect around 720cm of snow accumulation during this period. Winds are generally light, averaging 2km/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 Juneau 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.
