August weather forecast
Norwalk, IA

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Weather in August

August, the last month of the summer in Norwalk, is another warm month, with an average temperature fluctuating between 81.7°F (27.6°C) and 62.6°F (17°C).

Temperature

Norwalk experiences an average high-temperature of a still warm 81.7°F (27.6°C) in August, subtly different from July's 83.1°F (28.4°C). Norwalk usually reports an average low-temperature of 62.6°F (17°C) during the month of August.

Heat index

In August, the heat index is calculated to be a hot 87.8°F (31°C). With constant exposure and activity, a state of weariness might ensue, leading to potential heat cramps.
Regarding the heat index, one should be aware it's determined by shaded settings and mild winds. An exposure to direct sunlight may lift the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'feels like', is a measure of how hot it feels when the actual air humidity is factored in. The impact of weather on an individual can be subjective, affected by the person's activity and heat perception, which can vary due to elements including wind, clothing, and metabolic differences. Direct sun rays have a notable impact on perceived temperature, which can raise the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values hold particular significance for children. Children often fail to understand the importance of rest and rehydration. Thirst is a late manifestation of dehydration - hence, it is crucial to stay hydrated, especially during ongoing physical activities.

Humidity

The average relative humidity in August is 78%.

Rainfall

In Norwalk, Iowa, in August, during 11.8 rainfall days, 1.85" (47mm) of precipitation is typically accumulated. Throughout the year, there are 114.4 rainfall days, and 16.38" (416mm) of precipitation is accumulated.

Snowfall

In Norwalk, snow does not fall in June through September.

Daylight

In August, the average length of the day in Norwalk, Iowa, is 13h and 47min.
On the first day of August, sunrise is at 6:10 am and sunset at 8:31 pm. On the last day of the month, sunrise is at 6:40 am and sunset at 7:48 pm CDT.

Sunshine

In August, the average sunshine is 9.9h.

UV index

The months with the highest UV index are June through August, with an average maximum UV index of 6. A UV Index estimate of 6 to 7 represents a high health hazard from unsafe exposure to UV radiation for average individuals.
Note: A maximum high daily UV index of 6 during August translates into the following directions:
Take precautions against overexposure. Protection against sun damage is needed. Limit direct sun exposure especially between 10 a.m. and 4 p.m., when UV radiation is at its peak. However, keep in mind that shade structures may not provide full sun protection. For a sun-safe wardrobe, go for clothes that are tightly woven and generously sized.

Frequently asked questions

What are August temperatures?

During August, Norwalk experiences an average high-temperature of 81.7°F (27.6°C) and a low-temperature of 62.6°F (17°C). In August, the average heat index (a.k.a. 'apparent temperature', 'feels like'), which combines air temperature and relative humidity, is calculated to be 87.8°F (31°C).

What is the average humidity in August?

In Norwalk, the average relative humidity in August is 78%.

How much does it rain in August?

In Norwalk, during August, the rain falls for 11.8 days and regularly aggregates up to 1.85" (47mm) of precipitation.

When it does not snow?

In Norwalk, snow does not fall in June through September.

How many hours of daylight does Norwalk have in August?

In Norwalk, the average day length in August is 13h and 47min.

When is the sunrise / sunset in August?

In August, on the first day of the month, sunrise is at 6:10 am and sunset at 8:31 pm. On the last day of the month, sunrise is at 6:40 am and sunset at 7:48 pm CDT.

How many hours of sunshine does Norwalk have in August?

In August, the average sunshine duration is 9.9h.

When is the highest UV index?

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

What is the UV index intensity in August?

In Norwalk, the average daily maximum UV index in August is 6. A UV Index of 6 to 7 symbolizes a high hazard to health 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
Norwalk, IA

Average temperature in August - Norwalk, IA
  • Average high temperature in August: 81.7°F

The warmest month (with the highest average high temperature) is July (83.1°F).
The month with the lowest average high temperature is January (28.2°F).

  • Average low temperature in August: 62.6°F

The month with the highest average low temperature is July (65.5°F).
The coldest month (with the lowest average low temperature) is January (15.1°F).

Average pressure in August
Norwalk, IA

Average pressure in August - Norwalk, IA
  • Average pressure in August: 29.97"Hg

The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).

Average wind speed in August
Norwalk, IA

Average wind speed in August - Norwalk, IA
  • Average wind speed in August: 7mph

The windiest months (with the highest average wind speed) are January, February, March and April (10.3mph).
The calmest months (with the lowest average wind speed) are July and August (7mph).

Average humidity in August
Norwalk, IA

Average humidity in August - Norwalk, IA
  • Average humidity in August: 78%

The 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
Norwalk, IA

Average rainfall in August - Norwalk, IA
  • Average rainfall in August: 1.85"

The wettest month (with the highest rainfall) is May (2.76").
The driest month (with the least rainfall) is January (0.47").

Average rainfall days in August
Norwalk, IA

Average rainfall days in August - Norwalk, 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
Norwalk, IA

Average snowfall in August - Norwalk, IA
  • Average snowfall in August: 0"

The month with the highest snowfall is January (2.24").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in August
Norwalk, IA

Average snowfall days in August - Norwalk, IA
  • Average snowfall days in August: 0 days

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

Average daylight in August /
Average sunshine in August
Norwalk, IA

Average daylight in August / Average sunshine in August - Norwalk, IA
  • Average daylight in August: 13h and 5min

The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 12min).

  • Average sunshine in August: 9h and 5min

The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 18min).

Average sunshine days in August
Norwalk, IA

Average sunshine days in August - Norwalk, IA
  • Average sunshine days in August: 16.7 days

The month with the most sunshine days is December (22.3 days).
The month with the least sunshine days is June (12.2 days).

Average UV index in August
Norwalk, IA

Average UV index in August - Norwalk, IA
  • Average UV index in August: 6

The 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).

Average cloud cover in August
Norwalk, IA

Average cloud cover in August - Norwalk, IA
  • Average cloud cover in August: 30

The month with the most cloud cover is January (Cloud cover 54).
The months with the least cloud cover are July and September (Cloud cover 29).

Average visibility in August
Norwalk, IA

Average visibility in August - Norwalk, IA
  • Average visibility in August: 6mi

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

Norwalk, Iowa, USA

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