Contents
- Weather in August
- Frequently asked questions
- Average temperature in August
- Average pressure in August
- Average wind speed in August
- Average humidity in August
- Average rainfall in August
- Average rainfall days in August
- Average snowfall in August
- Average snowfall days in August
- Average daylight in August
- Average sunshine in August
- Average sunshine days in August
- Average UV index in August
- Average cloud cover in August
- Average visibility in August
Weather in August
Temperature
Monticello's shift into August is marked by a subtle change to a still warm 81°F (27.2°C) from July's 81.9°F (27.7°C) in temperature. Nighttime temperature dips to a mean of 63.3°F (17.4°C) during August.Heat index
The heat index in August is calculated to be a tropical 87.8°F (31°C). If one continues to be active during exposure, it might cause tiredness and subsequent heat cramps.Be advised, the heat index considers values for conditions in shade and with a light breeze. Direct exposure to sunlight could raise the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', comes about by integrating the temperature readings with the humidity levels. 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. Consider that direct sun exposure can intensify the felt heat, adding potentially 15 Fahrenheit (8 Celsius) degrees to the heat index. Heat index values remain especially vital for babies and toddlers. Younglings are generally more in peril than adults due to their reduced perspiration. Coupled with a larger skin surface relative to their tiny bodies and greater heat production because of their activity, they become more at risk.
Humidity
In August, the average relative humidity is 83%.Rainfall
In August, the rain falls for 12.4 days. Throughout August, 1.54" (39mm) of precipitation is accumulated. In Monticello, during the entire year, the rain falls for 127.9 days and collects up to 16.61" (422mm) of precipitation.Snowfall
In Monticello, snow does not fall in May through October.Daylight
In Monticello, the average length of the day in August is 13h and 42min.On the first day of August, sunrise is at 5:53 am and sunset at 8:07 pm. On the last day of the month, sunrise is at 6:21 am and sunset at 7:26 pm CDT.
Sunshine
The average sunshine in August is 9.7h.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 threat to health from unprotected exposure to Sun's UV rays for average individuals.Note: In August, an average UV index of 6 transforms into the following instructions:
Stand by precautions and apply sun safety measures. Evading sunburn is of great importance. The hours from 10 a.m. to 4 p.m. have the most intense UV radiation. As much as possible, limit direct sun exposure during this period. A wide-brim hat offers excellent sun protection for the eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in August?
What is the average humidity in August?
How much does it rain in August?
When it does not snow?
How many hours of daylight does Monticello have in August?
What time are sunrise and sunset in August?
How long on average sun shines in August?
When is the highest UV index?
What is the UV index reading in August in Monticello?
Average temperature in August
Monticello, IL
- Average high temperature in August: 81°F
The warmest month (with the highest average high temperature) is July (81.9°F).
The month with the lowest average high temperature is January (32.4°F).
- Average low temperature in August: 63.3°F
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (20.3°F).
Average pressure in August
Monticello, IL
- Average pressure in August: 29.98"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in August
Monticello, IL
- Average wind speed in August: 6.4mph
The windiest month (with the highest average wind speed) is January (10.9mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).
Average humidity in August
Monticello, IL
- Average humidity in August: 83%
The month with the highest relative humidity is July (85%).
The month with the lowest relative humidity is October (70%).
Average rainfall in August
Monticello, IL
- Average rainfall in August: 1.54"
The wettest month (with the highest rainfall) is May (2.09").
The driest month (with the least rainfall) is December (0.91").
Average rainfall days in August
Monticello, IL
- Average rainfall days in August: 12.4 days
The month with the highest number of rainy days is May (16.3 days).
The month with the least rainy days is February (5.2 days).
Average snowfall in August
Monticello, IL
- Average snowfall in August: 0"
The month with the highest snowfall is January (2.05").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in August
Monticello, IL
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is January (8.3 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in August /
Average sunshine in August
Monticello, IL
- Average daylight in August: 13h and 4min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in August: 9h and 4min
The month with the most sunshine is June (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days in August
Monticello, IL
- Average sunshine days in August: 15.9 days
The month with the most sunshine days is November (19.6 days).
The month with the least sunshine days is May (12.3 days).
Average UV index in August
Monticello, IL
- Average UV index in August: 6
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in August
Monticello, IL
- Average cloud cover in August: 32
The month with the most cloud cover is January (Cloud cover 57).
The months with the least cloud cover are June, August and September (Cloud cover 32).
Average visibility in August
Monticello, IL
- Average visibility in August: 5mi
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
Monticello, Illinois, USA
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