August weather forecastDerby, IA
August
Weather in August
The last month of the summer, August, is also a moderately hot month in Derby, Iowa, with an average temperature varying between 62.8°F (17.1°C) and 81.7°F (27.6°C).Temperature
The transition from July to August brings an average high-temperature of a still warm 81.7°F (27.6°C), barely different from July's 83.1°F (28.4°C). During August, Derby consistently records a temperature low averaging a comfortable 62.8°F (17.1°C).Heat index
The heat index in August is evaluated at a tropical 87.8°F (31°C). With sustained exposure and activity, exhaustion becomes probable, resulting in heat cramps.Note that heat index values are valued for light wind and location in the shade. Direct sunlight exposure may result in a rise of the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', combines both the air temperature and the humidity level to give a perceived human temperature. An individual's perception of weather can be swayed by a variety of elements including metabolic differences, pregnancy status, and their level of physical exertion. Be mindful that being in direct sunlight might mean feeling hotter, with the heat index rising by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are primarily vital for children. In general, younger individuals are at greater risk than adults because they tend to sweat less. Also, having a larger skin surface to body size ratio and greater heat production due to their active behavior contribute to this danger.
Humidity
The average relative humidity in August in Derby is 79%.Rainfall
In Derby, in August, during 12.7 rainfall days, 2.32" (59mm) of precipitation is typically accumulated. Throughout the year, there are 131.1 rainfall days, and 25.71" (653mm) of precipitation is accumulated.Snowfall
In Derby, snow does not fall in June through September.Daylight
In Derby, Iowa, the average length of the day in August is 13h and 46min.On the first day of the month, sunrise is at 6:10 am and sunset at 8:29 pm. On the last day of August, sunrise is at 6:40 am and sunset at 7:47 pm CDT.
Sunshine
In Derby, the average sunshine in August is 9.7h.UV index
The months with the highest UV index in Derby are June through August, with an average maximum UV index of 6. A UV Index of 6 to 7 symbolizes a high health risk from exposure to the Sun's UV rays for the ordinary person.Note: In August, the maximum UV index of 6 suggests these recommendations:
Apply measures and align with sun safety principles. Safeguarding against skin and eye injury is pivotal. Avoid direct sunlight between the hours of 10 a.m. and 4 p.m., when UV radiation is at its peak. Keep in mind that shade structures may not provide complete protection. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
Derby, 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 (29.3°F).
- Average low temperature in August: 62.8°F
The month with the highest average low temperature is July (65.7°F).
The coldest month (with the lowest average low temperature) is January (16°F).
Average pressure in August
Derby, IA
- Average pressure in August: 29.96"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in August
Derby, IA
- Average wind speed in August: 7.1mph
The windiest month (with the highest average wind speed) is January (10.7mph).
The calmest months (with the lowest average wind speed) are July and August (7.1mph).
Average humidity in August
Derby, IA
- Average humidity in August: 79%
The month with the highest relative humidity is June (83%).
The month with the lowest relative humidity is October (72%).
Average rainfall in August
Derby, IA
- Average rainfall in August: 2.32"
The wettest month (with the highest rainfall) is June (3.74").
The driest month (with the least rainfall) is January (0.94").
Average rainfall days in August
Derby, IA
- Average rainfall days in August: 12.7 days
The month with the highest number of rainy days is May (16.7 days).
The month with the least rainy days is January (4.7 days).
Average snowfall in August
Derby, IA
- Average snowfall in August: 0"
The month with the highest snowfall is February (4.13").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in August
Derby, IA
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is January (10.2 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in August /
Average sunshine in August
Derby, IA
- Average daylight in August: 13h and 48min
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 18min).
- Average sunshine in August: 9h and 42min
The month with the most sunshine is July (Average sunshine: 10h and 12min).
The month with the least sunshine is January (Average sunshine: 4h and 12min).
Average sunshine days in August
Derby, IA
- Average sunshine days in August: 16 days
The month with the most sunshine days is November (19.3 days).
The month with the least sunshine days is June (10.7 days).
Average UV index in August
Derby, 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
Derby, 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 August (Cloud cover 30).
Average visibility in August
Derby, IA
- Average visibility in August: 5mi
The months with the highest visibility are February, March, April, May, June, July, September, October, November and December (6mi).
The months with the lowest visibility are January and August (5mi).
