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

May 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
May, the last month of the spring, in Juneau, is a frosty month, with temperature in the range of an average low of 40.6°F (4.8°C) and an average high of 47.5°F (8.6°C).

Temperature

In May, the average high-temperature rises, from a wintry 37°F (2.8°C) in April, to a chilly 47.5°F (8.6°C). In May, the average low-temperature is 40.6°F (4.8°C).

Humidity

May is the least humid month in Juneau, with an average relative humidity of 86%.

Rainfall

May is the month with the least rainfall. Rain falls for 18.5 days and accumulates 4.13" (105mm) of precipitation.

Snowfall

January through May, October through December are months with snowfall. May is the last month it regularly snows in Juneau. During 3.2 snowfall days, Juneau aggregates 3.31" (84mm) of snow. In Juneau, during the entire year, snow falls for 126.6 days, and aggregates up to 290.12" (7369mm) of snow.

Ocean temperature

In Juneau, the average water temperature is 44.2°F (6.8°C).
Note: Swimming in 44.2°F (6.8°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

The average length of the day in May is 16.8h.

Sunshine

In Juneau, the average sunshine is 6.2h.

UV index

Months with the highest UV index in Juneau are May and July, with an average maximum UV index of 3. A UV Index of 3 to 5 symbolizes a medium health hazard from the exposure to the Sun's UV rays for the average person.
Note: In May, 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 solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. 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. Caution! The reflection of snow can nearly double the intensity of the Sun's UV radiation.

What is the temperature in May in Juneau?

The average high-temperature, in May, in Juneau, Alaska, is 47.5°F (8.6°C), while the average low-temperature is 40.6°F (4.8°C).

What is the least humid month in Juneau?

May is the least humid month in Juneau, with an average relative humidity of 86%.

What is the average humidity in May in Juneau?

In May, the average relative humidity in Juneau is 86%.

How much does it rain in Juneau in May?

In Juneau, Alaska, in May, during 18.5 rainfall days, 4.13" (105mm) of precipitation is typically accumulated.

What is the driest month in Juneau?

May is the month with the least rainfall. Rain falls for 18.5 days and accumulates 4.13" (105mm) of precipitation.

What is the last month it snows in Juneau?

May is the last month it regularly snows in Juneau, Alaska. During 3.2 snowfall days, in May, Juneau aggregates 3.31" (84mm) of snow.

How cold is the water in May in Juneau?

In Juneau, Alaska, the average seawater temperature in May is 44.2°F (6.8°C). Swimming in 44.2°F (6.8°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.

What is the average length of the day in May in Juneau?

The average length of the day in May in Juneau is 16.8h.

How long on average sun shines in May in Juneau?

In May, the average sunshine in Juneau is 6.2h.

What are the months with the highest UV index in Juneau?

May and July, with an average maximum UV index of 3, are months with the highest UV index.

What is the UV index reading in May in Juneau?

In Juneau, the average daily maximum UV index in May is 3. A UV Index estimate of 3 to 5 represents a moderate vulnerability from unsafe exposure to the Sun's UV rays.
Average temperature in May - Juneau, AK
  • Average high temperature in May: 47.5°F

The warmest month (with the highest average high temperature) is July (55.8°F).
Months with the lowest average high temperature are January and December (25.7°F).

  • Average low temperature in May: 40.6°F

The month with the highest average low temperature is July (50°F).
The coldest month (with the lowest average low temperature) is January (23.7°F).

Average humidity in May - Juneau, AK
  • Average humidity in May: 86%

The month with the highest relative humidity is January (92%).
The month with the lowest relative humidity is May (86%).

Average rainfall in May - Juneau, AK
  • Average rainfall in May: 4.13"

The wettest month (with the highest rainfall) is October (9.88").
The driest month (with the lowest rainfall) is May (4.13").

Average rainfall days in May - Juneau, AK
  • Average rainfall days in May: 18.5 days

The month with the highest number of rainy days is September (21.9 days).
The month with the lowest number of rainy days is February (4.8 days).

Average snowfall in May - Juneau, AK
  • Average snowfall in May: 3.31"

The month with the highest snowfall is December (62.8").
Months with the lowest snowfall are June, July, August and September (0").

Average snowfall days in May - Juneau, AK
  • Average snowfall days in May: 3.2 days

The month with the highest number of snowfall days is January (21.9 days).
Months with the lowest number of snowfall days are June, July, August and September (0 days).

Average sea temperature in May - Juneau, AK
  • Average sea temperature in May: 44.1°F

The best month for swimming (with the highest average sea temperature) is August (53.5°F).
The coldest month (with the lowest average sea temperature) is March (40.3°F).

Average daylight in May / Average sunshine in May - Juneau, AK
  • Average daylight in May: 16.8h

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 May: 6.2h

The month with most sunshine is June (Average sunshine: 6.4h).
The month with least sunshine is November (Average sunshine: 2.6h).

Average UV index in May - Juneau, AK
  • Average UV index in May: 3

Months with the highest UV index are May and July (UV index 3).
Months with the lowest UV index are January, April, October, November and December (UV index 1).