Des Moines
Iowa, USA
Long-term weather forecast
Long-term weather forecast

August weather forecast and climate
Des Moines, IA

The last month of the summer, August, is another warm month in Des Moines, Iowa, with temperature in the range of an average high of 81.7°F (27.6°C) and an average low of 62.6°F (17°C).

Temperature

In Des Moines, the average high-temperature is essentially the same as in July - a still moderately hot 81.7°F (27.6°C). In August, in Des Moines, Iowa, the average low-temperature is 62.6°F (17°C).

Heat index

In August, the average heat index is evaluated at a tropical 87.6°F (30.9°C). Exhaustion is likely with prolonged exposure and activity. Sustaining activity may result in heat cramps.
Take into consideration that the heat index values are calculated for shade and light wind conditions. With the exposure to direct sunlight, the heat index may be increased by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature', 'real feel', 'apparent temperature', or 'feels like', is calculated by taking the relative humidity value for a specific location and factoring it into the air temperature reading. Additional factors like activity, metabolic differences, differences in body mass, height, and shape, and clothing affect individual temperature impact. Bear in mind that direct sunshine exposure increases weather impact, and may raise heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly important for children. Young children are generally more endangered than adults, as they usually less sweat. And also, due to larger skin surface relative to their small bodies and higher heat production as a result of their activity.

Humidity

In August, the average relative humidity is 78%.

Rainfall

In Des Moines, in August, during 11.8 rainfall days, 1.85" (47mm) of precipitation is typically accumulated. In Des Moines, during the entire year, the rain falls for 114.4 days and collects up to 16.38" (416mm) of precipitation.

Snowfall

June through September are months without snowfall.

Daylight

In August, the average length of the day in Des Moines is 13.8h.

Sunshine

In August, the average sunshine is 9.9h.

UV index

June through August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health risk from unsafe exposure to the UV radiation for average individuals.
Note: In August, the average maximum UV index of 6 translate into the following recommendations:
Take precautions and utilize sun safety practices. Protection against the skin and eye damage is required. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. 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 Des Moines?

In August, in Des Moines, the average high-temperature is 81.7°F (27.6°C), and the average low-temperature is 62.6°F (17°C). The average heat index (a.k.a. 'apparent temperature', 'feels like'), that calculates temperature value influenced by the moisture in the air, in August is calculated to 87.6°F (30.9°C).

What is the average humidity in August in Des Moines?

The average relative humidity in August in Des Moines is 78%.

How much does it rain in Des Moines in August?

In Des Moines, in August, it is raining for 11.8 days, with typically 1.85" (47mm) of accumulated precipitation.

When it does not snow in Des Moines?

June through September are months without snowfall in Des Moines, Iowa.

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

The average length of the day in August in Des Moines, Iowa, is 13.8h.

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

In August, the average sunshine in Des Moines, Iowa, is 9.9h.

When is the highest UV index in Des Moines?

June through August, with an average maximum UV index of 6, are months with the highest UV index.

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

In August, the average daily maximum UV index in Des Moines, Iowa, is 6. A UV Index estimate of 6 to 7 represents a high health vulnerability from unsafe exposure to the Sun's UV rays.
Average temperature in August - Des Moines, IA
  • Average high temperature in August: 27.6°C

The warmest month (with the highest average high temperature) is July (28.4°C).
The month with the lowest average high temperature is January (-2.1°C).

  • Average low temperature in August: 17°C

The month with the highest average low temperature is July (18.6°C).
The coldest month (with the lowest average low temperature) is January (-9.4°C).

Average humidity in August - Des Moines, IA
  • Average humidity in August: 78%

Months with the highest relative humidity are January and June (82%).
The month with the lowest relative humidity is October (70%).

Average rainfall in August - Des Moines, IA
  • Average rainfall in August: 47mm

The wettest month (with the highest rainfall) is May (70mm).
The driest month (with the least rainfall) is January (12mm).

Average rainfall days in August - Des Moines, IA
  • Average rainfall days in August: 11.8 days

The month with the highest number of rainy days is June (15.9 days).
The month with the least rainy days is February (3 days).

Average snowfall in August - Des Moines, IA
  • Average snowfall in August: 0mm

The month with the highest snowfall is January (57mm).
Months with the least snowfall are June, July, August and September (0mm).

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

The month with the highest number of snowfall days is January (8.7 days).
Months with the least snowfall days are June, July, August and September (0 days).

Average daylight in August / Average sunshine in August - Des Moines, IA
  • Average daylight in August: 13.8h

The month with the longest days is June (Average daylight: 15.2h).
The month with the shortest days is December (Average daylight: 9.2h).

  • Average sunshine in August: 9.9h

The month with the most sunshine is July (Average sunshine: 10.3h).
The month with the least sunshine is January (Average sunshine: 4.3h).

Average UV index in August - Des Moines, IA
  • Average UV index in August: 6

Months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is January (UV index 1).