August weather forecast
Des Moines, WA

Share

Weather in August

The last month of the summer, August, is also a moderately hot month in Des Moines, Washington, with an average temperature fluctuating between 77.7°F (25.4°C) and 53.6°F (12°C).

Temperature

Des Moines's August weather, with an average high temperature of 77.7°F (25.4°C) and an average low temperature of 53.6°F (12°C), tends to be the warmest of the year.

Humidity

In August, the average relative humidity is 69%.

Rainfall

In Des Moines, in August, during 5.7 rainfall days, 0.47" (12mm) of precipitation is typically accumulated. In Des Moines, during the entire year, the rain falls for 138.2 days and collects up to 14.09" (358mm) of precipitation.

Snowfall

April through October are months without snowfall in Des Moines.

Ocean temperature

The month with the warmest seawater is August, with an average ocean temperature of 53.8°F (12.1°C).
Note: Unprotected swimming in 53.8°F (12.1°C) is dangerous due to potential cold shock. Especially when temperatures go below 50°F (10°C), leading to hyperventilation.

Daylight

In Des Moines, the average length of the day in August is 14h and 11min.
On the first day of the month, sunrise is at 5:48 am and sunset at 8:42 pm. On the last day of August, in Des Moines, sunrise is at 6:28 am and sunset at 7:50 pm PDT.

Sunshine

The month with the most sunshine is August, with an average of 10.7h of sunshine.

UV index

The months with the highest UV index are June through August, with an average maximum UV index of 5. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for the average person.
Note: A typical high UV index of 5 in August suggests the following recommendations:
Ensure safety - Sun damage prevention is strongly urged. Direct Sun exposure should be minimized especially during midday when radiation is most intense. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Updated: Feb 14, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the warmest month in Des Moines?

In Des Moines, August registers the highest temperatures, averaging 77.7°F (25.4°C) at the peak and 53.6°F (12°C) at the lowest.

What is the average August temperature in Des Moines?

August temperatures vary between a high-temperature of 77.7°F (25.4°C) and a low-temperature of 53.6°F (12°C).

What is the average humidity in August in Des Moines?

In Des Moines, the average relative humidity in August is 69%.

How many days does it rain in August in Des Moines?

In August, in Des Moines, Washington, the rain falls for 5.7 days. Throughout August, 0.47" (12mm) of precipitation is accumulated.

When it does not snow in Des Moines?

In Des Moines, snow does not fall in April through October.

When is the ocean warmest in Des Moines?

August is the month with the warmest seawater in Des Moines, with an average ocean temperature of 53.8°F (12.1°C).

How cold is the water in August in Des Moines?

In Des Moines, in August, the average water temperature is 53.8°F (12.1°C). At temperatures below 50°F (10°C), swimming in a suitably protected swimsuit is feasible; otherwise, cold shock and loss of breathing control are imminent. Even a short swim, without thermal protection, at temperatures around 55.4°F (13°C) is not comfortable.

How many hours of daylight does Des Moines have in August?

In August, the average day length in Des Moines, Washington, is 14h and 11min.

When is the sunrise / sunset in August in Des Moines?

In August, on the first day of the month, sunrise is at 5:48 am and sunset at 8:42 pm. On the last day of the month, in Des Moines, Washington, sunrise is at 6:28 am and sunset at 7:50 pm PDT.

What month has the most sunshine in Des Moines?

August has the most sunshine of the year in Des Moines, with an average of 10.7h of sunshine.

How long on average sun shines in August in Des Moines?

The average sunshine duration in August in Des Moines is 10.7h.

What are the months with the highest UV index in Des Moines?

The months with the highest UV index in Des Moines, Washington, are June through August, with an average maximum UV index of 5.

What is the UV index intensity in August in Des Moines?

In August, the average daily maximum UV index in Des Moines is 5. A UV Index value 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
Des Moines, WA

Average temperature in August - Des Moines, WA
  • Average high temperature in August: 77.7°F

The warmest month (with the highest average high temperature) is August (77.7°F).
The month with the lowest average high temperature is December (43.5°F).

  • Average low temperature in August: 53.6°F

The month with the highest average low temperature is August (53.6°F).
The coldest month (with the lowest average low temperature) is December (34.3°F).

Average pressure in August
Des Moines, WA

Average pressure in August - Des Moines, WA
  • Average pressure in August: 30.01"Hg

The month with the highest atmospheric pressure is January (30.1"Hg).
The months with the lowest atmospheric pressure are March, August and September (30.01"Hg).

Average wind speed in August
Des Moines, WA

Average wind speed in August - Des Moines, WA
  • Average wind speed in August: 3.6mph

The windiest month (with the highest average wind speed) is March (5.3mph).
The calmest months (with the lowest average wind speed) are July and August (3.6mph).

Average humidity in August
Des Moines, WA

Average humidity in August - Des Moines, WA
  • Average humidity in August: 69%

The months with the highest relative humidity are January and December (85%).
The month with the lowest relative humidity is July (68%).

Average rainfall in August
Des Moines, WA

Average rainfall in August - Des Moines, WA
  • Average rainfall in August: 0.47"

The wettest month (with the highest rainfall) is December (2.2").
The driest month (with the least rainfall) is July (0.31").

Average rainfall days in August
Des Moines, WA

Average rainfall days in August - Des Moines, WA
  • Average rainfall days in August: 5.7 days

The month with the highest number of rainy days is April (14.9 days).
The month with the least rainy days is August (5.7 days).

Average snowfall in August
Des Moines, WA

Average snowfall in August - Des Moines, WA
  • Average snowfall in August: 0"

The month with the highest snowfall is February (2.52").
The months with the least snowfall are April, May, June, July, August, September and October (0").

Average snowfall days in August
Des Moines, WA

Average snowfall days in August - Des Moines, WA
  • Average snowfall days in August: 0 days

The month with the highest number of snowfall days is February (3.4 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).

Average sea temperature in August
Des Moines, WA

Average sea temperature in August - Des Moines, WA
  • Average sea temperature in August: 53.7°F

The best month for swimming (with the highest average sea temperature) is August (53.7°F).
The coldest month (with the lowest average sea temperature) is February (45.8°F).

Average daylight in August /
Average sunshine in August
Des Moines, WA

Average daylight in August / Average sunshine in August - Des Moines, 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 4min

The month with the most sunshine is August (Average sunshine: 10h and 42min).
The month with the least sunshine is December (Average sunshine: 4h and 6min).

Average sunshine days in August
Des Moines, WA

Average sunshine days in August - Des Moines, WA
  • Average sunshine days in August: 22.8 days

The month with the most sunshine days is August (22.8 days).
The month with the least sunshine days is February (13 days).

Average UV index in August
Des Moines, WA

Average UV index in August - Des Moines, WA
  • Average UV index in August: 5

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

Average cloud cover in August
Des Moines, WA

Average cloud cover in August - Des Moines, WA
  • Average cloud cover in August: 26

The month with the most cloud cover is December (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 26).

Average visibility in August
Des Moines, WA

Average visibility in August - Des Moines, WA
  • Average visibility in August: 6mi

The months with the highest visibility are May, June, July, August and September (6mi).
The months with the lowest visibility are January, February, March, April, October, November and December (5mi).

Des Moines, Washington, USA

Weather forecast for your location

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