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

August weather forecast and climate
Juneau, AK

Blooming fireweed in Juneau, Alaska, with snowy mountain peaks in the distance
Blooming fireweed in Juneau, Alaska, with snowy mountain peaks in the distance
August, the last month of the summer, in Juneau, is another comfortable month, with average temperature fluctuating between 62.8°F (17.1°C) and 48.9°F (9.4°C).

Temperature

In August, the average high-temperature is practically the same as in July - a still comfortable 62.8°F (17.1°C). In August, in Juneau, the average low-temperature is 48.9°F (9.4°C).

Humidity

In Juneau, the average relative humidity is 84.3%.

Rainfall

In Juneau, in August, it is raining for 19.1 days, with typically 5.7" (145.5mm) of accumulated precipitation. In Juneau, during the entire year, the rain falls for 229.8 days and collects up to 62.3" (1581.6mm) of precipitation.

Snowfall

May through September are months without snowfall.

Ocean temperature

With an average ocean temperature of 53.4°F (11.9°C), August is the month with the warmest seawater in Juneau.
Note: Swimming in 53.4°F (11.9°C) is considered dangerous. Unprotected immersion in temperatures below 50°F (10°C) causes quickly maximum intensity cold shock with hyperventilation.

Daylight

In Juneau, the average length of the day is 15.3h.

Sunshine

The average sunshine in Juneau is 5.2h.

UV index

In August, the average daily maximum UV index in Juneau is 4. A UV Index reading of 3 to 5 represents a medium vulnerability from unprotected exposure to the Sun's UV rays for ordinary individuals.
Note: The daily maximum UV index of 4 in August interpret into the following advice:
Take precautions. Light skin individuals may get burned in less than 30 minutes. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. 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.

What is the temperature in August in Juneau?

The average high-temperature, in August, in Juneau, Alaska, is 62.8°F (17.1°C), while the average low-temperature is 48.9°F (9.4°C).

What is the average humidity in August in Juneau?

The average relative humidity in August in Juneau, Alaska, is 84.3%.

How much does it rain in Juneau in August?

In Juneau, in August, it is raining for 19.1 days, with typically 5.7" (145.5mm) of accumulated precipitation.

When it does not snow in Juneau?

In Juneau snow does not fall in May through September.

What month is the ocean warmest in Juneau?

The month with the warmest seawater is August, with an average ocean temperature of 53.4°F (11.9°C).

What is the water temperature in August in Juneau?

In August, the average ocean temperature in Juneau, Alaska, is 53.4°F (11.9°C). Swimming in 53.4°F (11.9°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.

How many hours of daylight does Juneau have in August?

The average length of the day in August in Juneau, Alaska, is 15.3h.

How long on average sun shines in August in Juneau?

The average sunshine in August in Juneau is 5.2h.

What is the UV index intensity in August in Juneau?

In Juneau, the average daily maximum UV index in August is 4. A UV Index estimate of 3 to 5 represents a medium hazard to health from unprotected exposure to the UV radiation.
Average temperature in August - Juneau, AK
  • Average high temperature in August: 17.1°C

The warmest month (with the highest average high temperature) is July (17.7°C).
The month with the lowest average high temperature is January (0.4°C).

  • Average low temperature in August: 9.4°C

The month with the highest average low temperature is July (10°C).
The coldest month (with the lowest average low temperature) is January (-4.6°C).

Average humidity in August - Juneau, AK
  • Average humidity in August: 84.3%

The month with the highest relative humidity is September (87.9%).
The month with the lowest relative humidity is May (76.3%).

Average rainfall in August - Juneau, AK
  • Average rainfall in August: 145.5mm

The wettest month (with the highest rainfall) is September (219.5mm).
The driest month (with the lowest rainfall) is April (74.7mm).

Average rainfall days in August - Juneau, AK
  • Average rainfall days in August: 19.1 days

The month with the highest number of rainy days is October (23.9 days).
The month with the lowest number of rainy days is June (15.8 days).

Average snowfall in August - Juneau, AK
  • Average snowfall in August: 0mm

The month with the highest snowfall is January (703.6mm).
Months with the lowest snowfall are May, June, July, August and September (0mm).

Average snowfall days in August - Juneau, AK
  • Average snowfall days in August: 0 days

The month with the highest number of snowfall days is January (10.6 days).
Months with the lowest number of snowfall days are May, June, July, August and September (0 days).

Average sea temperature in August - Juneau, AK
  • Average sea temperature in August: 11.9°C

The best month for swimming (with the highest average sea temperature) is August (11.9°C).
The coldest month (with the lowest average sea temperature) is March (4.7°C).

Average daylight in August / Average sunshine in August - Juneau, AK
  • Average daylight in August: 15.3h

The month with the longest days is June (Average daylight: 18.2h).
The month with shortest days is December (Average daylight: 6.5h).

  • Average sunshine in August: 5.2h

The month with most sunshine is May (Average sunshine: 7.5h).
The month with least sunshine is December (Average sunshine: 1.3h).

Average UV index in August - Juneau, AK
  • Average UV index in August: 4

Months with the highest UV index are June and July (UV index 5).
Months with the lowest UV index are January, November and December (UV index 0).