August weather forecast
Issaquah, WA

englishespañol中文
Share

Weather in August

August carries forward the warm temperatures from July with a further increase to 77°F (25°C) on average. The rainfall also shows an infinitesimal rise to 0.28" (7mm). Meanwhile, the evenings stay warmer as August records the highest average low temperature in the year at 51.4°F (10.8°C). The cloud cover marginally increases from 29% in July to 27% in August. Overall, the weather in August in Issaquah is characteristically warm, sunny, and mildly humid.

Temperature

The average temperatures reach their apex in August, averaging 77°F (25°C) at the high end and 51.4°F (10.8°C) at the low end.

Humidity

The average relative humidity in August is 71%.

Rainfall

In Issaquah, during August, the rain falls for 4.3 days and regularly aggregates up to 0.28" (7mm) of precipitation. Throughout the year, there are 127.4 rainfall days, and 12.52" (318mm) of precipitation is accumulated.

Snowfall

In Issaquah, snow does not fall in May through October.

Daylight

The average length of the day in August is 14h and 12min.
On the first day of the month, sunrise is at 5:47 am and sunset at 8:41 pm. On the last day of August, sunrise is at 6:26 am and sunset at 7:49 pm PDT.

Sunshine

With an average of 10.5h of sunshine, August has the most sunshine of the year in Issaquah.

UV index

In August, the average daily maximum UV index is 4. A UV Index value of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV radiation for the ordinary person.
Note: The daily high UV index of 4 in August translates into this advice:
Be careful. Light complexion individuals might get burns in fewer than 30 minutes. For skin protection, it's recommended to minimize Sun exposure during its peak hours around midday. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades.
[Resources]

Frequently asked questions

What is the warmest month in Issaquah?

August, with average temperatures reaching a high of 77°F (25°C) and a low of 51.4°F (10.8°C), is the warmest month in Issaquah.

What is the temperature in August in Issaquah?

The high-temperature in Issaquah, Washington, during August is 77°F (25°C) and the low-temperature is 51.4°F (10.8°C).

What is the average humidity in August in Issaquah?

In Issaquah, the average relative humidity in August is 71%.

How many days does it rain in August in Issaquah?

In Issaquah, Washington, during August, the rain falls for 4.3 days and regularly aggregates up to 0.28" (7mm) of precipitation.

When it does not snow in Issaquah?

In Issaquah, snow does not fall in May through October.

How many hours of daylight does Issaquah have in August?

In August, the average day length in Issaquah is 14h and 12min.

When are sunrise and sunset in August in Issaquah?

In August, on the first day of the month, sunrise is at 5:47 am and sunset at 8:41 pm. On the last day of the month, in Issaquah, Washington, sunrise is at 6:26 am and sunset at 7:49 pm PDT.

What month has the most sunshine in Issaquah?

With an average of 10.5h of sunshine, August has the most sunshine of the year in Issaquah.

How many hours of sunshine does Issaquah have in August?

In August, the average sunshine duration in Issaquah, Washington, is 10.5h.

What is the UV index reading in August in Issaquah?

In Issaquah, the average daily maximum UV index in August is 4. A UV Index of 3 to 5 symbolizes a moderate vulnerability from unsafe exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in August
Issaquah, WA

Average temperature in August - Issaquah, WA
  • Average high temperature in August: 77°F

The warmest month (with the highest average high temperature) is August (77°F).
The month with the lowest average high temperature is December (42.3°F).

  • Average low temperature in August: 51.4°F

The month with the highest average low temperature is August (51.4°F).
The coldest months (with the lowest average low temperature) are February and December (33.4°F).

[Resources]

Average pressure in August
Issaquah, WA

Average pressure in August - Issaquah, WA
  • Average pressure in August: 30"Hg

The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is August (30"Hg).

[Resources]

Average wind speed in August
Issaquah, WA

Average wind speed in August - Issaquah, WA
  • Average wind speed in August: 3.4mph

The windiest month (with the highest average wind speed) is January (5.1mph).
The calmest month (with the lowest average wind speed) is August (3.4mph).

[Resources]

Average humidity in August
Issaquah, WA

Average humidity in August - Issaquah, WA
  • Average humidity in August: 71%

The months with the highest relative humidity are January and February (85%).
The month with the lowest relative humidity is July (69%).

[Resources]

Average rainfall in August
Issaquah, WA

Average rainfall in August - Issaquah, WA
  • Average rainfall in August: 0.28"

The wettest month (with the highest rainfall) is December (2.01").
The driest month (with the least rainfall) is July (0.24").

[Resources]

Average rainfall days in August
Issaquah, WA

Average rainfall days in August - Issaquah, WA
  • Average rainfall days in August: 4.3 days

The month with the highest number of rainy days is March (14.8 days).
The month with the least rainy days is August (4.3 days).

[Resources]

Average snowfall in August
Issaquah, WA

Average snowfall in August - Issaquah, WA
  • Average snowfall in August: 0"

The month with the highest snowfall is February (0.94").
The months with the least snowfall are May, June, July, August, September and October (0").

[Resources]

Average snowfall days in August
Issaquah, WA

Average snowfall days in August - Issaquah, WA
  • Average snowfall days in August: 0 days

The month with the highest number of snowfall days is February (2.5 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).

[Resources]

Average daylight in August /
Average sunshine in August
Issaquah, WA

Average daylight in August / Average sunshine in August - Issaquah, WA
  • Average daylight in August: 14h and 1min

The month with the longest days is June (Average daylight: 15h and 54min).
The month with the shortest days is December (Average daylight: 8h and 30min).

  • Average sunshine in August: 10h and 3min

The month with the most sunshine is August (Average sunshine: 10h and 30min).
The month with the least sunshine is December (Average sunshine: 4h and 0min).

[Resources]

Average sunshine days in August
Issaquah, WA

Average sunshine days in August - Issaquah, WA
  • Average sunshine days in August: 25 days

The month with the most sunshine days is August (25 days).
The month with the least sunshine days is February (12.9 days).

[Resources]

Average UV index in August
Issaquah, WA

Average UV index in August - Issaquah, WA
  • Average UV index in August: 4

The month with the highest UV index is July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).

[Resources]

Average cloud cover in August
Issaquah, WA

Average cloud cover in August - Issaquah, WA
  • Average cloud cover in August: 27

The months with the most cloud cover are January and December (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 27).

[Resources]

Average visibility in August
Issaquah, WA

Average visibility in August - Issaquah, WA
  • Average visibility in August: 6mi

The months with the highest visibility are July and August (6mi).
The months with the lowest visibility are January, February and December (4mi).

[Resources]

Issaquah, Washington, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location