July weather forecast
Grafton, IL

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Weather in July

July in Grafton, Illinois, is a hot summer month, with an average temperature ranging between max 86.4°F (30.2°C) and min 68.2°F (20.1°C).

Temperature

In Grafton, July records the highest average temperatures, peaking at 86.4°F (30.2°C) and reaching a low of 68.2°F (20.1°C).

Heat index

For most parts of July, the heat index is evaluated at a sweltering 100.4°F (38°C). Ensure heightened precautions, risk of heat cramps and heat exhaustion is significant. Sustained activity could provoke heatstroke.
Thinking about the heat index, one should account for its values in shaded areas with gentle breezes. Exposing to direct sunshine may enhance heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'apparent temperature', represents the fusion of temperature and moisture in the air to suggest how warm it feels. Factors such as metabolic variations, being pregnant, and physical activity can impact an individual's weather perception. Awareness of direct sun exposure is crucial as it has the potential to heighten the weather's effects, pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly critical to babies and toddlers. Youngsters generally face more threats than adults given their lesser ability to sweat. Coupled with their larger skin surface relative to their small bodies and higher heat production due to their activities, they are more endangered.
In high temperatures, perspiration kicks in, allowing the human body to cool down through the evaporation of sweat. When there is an excess of moisture in the atmosphere, the efficiency of the evaporation process is lessened, leading to less efficient body cooling and a sensation of overheating. Overheating and dehydration threats arise when heat gain goes beyond what the body can comfortably shed.

Humidity

In July, the average relative humidity is 78%.

Rainfall

In Grafton, in July, it is raining for 16.3 days, with typically 2.68" (68mm) of accumulated precipitation. In Grafton, during the entire year, the rain falls for 138.8 days and collects up to 27.6" (701mm) of precipitation.

Snowfall

April through October are months without snowfall in Grafton.

Daylight

The average length of the day in July is 14h and 35min.
On the first day of the month, sunrise is at 5:40 am and sunset at 8:31 pm. On the last day of July, sunrise is at 6:02 am and sunset at 8:13 pm CDT.

Sunshine

June and July, with an average of 10.4h of sunshine, are months with the most sunshine in Grafton.

UV index

May through August, with an average maximum UV index of 6, are months with the highest UV index in Grafton. A UV Index estimate of 6 to 7 represents a high health risk from exposure to the Sun's UV rays for the ordinary person.
Note: The maximum daily UV index of 6 in July converts into the following recommendations:
Apply measures and align with sun safety principles. Safeguarding against skin and eye injury is pivotal. From 10 a.m. to 4 p.m., when UV radiation is at its strongest, limit direct exposure to the Sun and note that shade structures may not provide full sun protection. Employ a wide-brim hat for potent defense against up to 50% of UV rays.
Updated: Feb 12, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the warmest month in Grafton?

Grafton, Illinois, records the warmest temperatures in July, averaging a high of 86.4°F (30.2°C) and a low of 68.2°F (20.1°C).

Is it hot in Grafton during July?

The average high-temperature, in July, in Grafton, is 86.4°F (30.2°C), while the average low-temperature is 68.2°F (20.1°C). The average heat index (a.k.a. 'apparent temperature', 'feels like'), which factors the actual air temperature with the relative humidity, in July is evaluated at 100.4°F (38°C).

What is the average humidity in July in Grafton?

The average relative humidity in July is 78%.

How many days does it rain in July in Grafton?

In Grafton, during July, the rain falls for 16.3 days and regularly aggregates up to 2.68" (68mm) of precipitation.

When it does not snow in Grafton?

April through October are months without snowfall.

How many hours of daylight does Grafton have in July?

In Grafton, Illinois, the average day length in July is 14h and 35min.

When is the sunrise / sunset in July in Grafton?

On the first day of July in Grafton, Illinois, sunrise is at 5:40 am and sunset at 8:31 pm. On the last day of the month, sunrise is at 6:02 am and sunset at 8:13 pm CDT.

What is the month with the most sunshine in Grafton?

June and July, with an average of 10.4h of sunshine, are months with the most sunshine in Grafton.

How many hours of sunshine does Grafton have in July?

In Grafton, the average sunshine duration in July is 10.4h.

When is the highest UV index in Grafton?

The months with the highest UV index in Grafton, Illinois, are May through August, with an average maximum UV index of 6.

How high is the UV index in July in Grafton?

In July, the average daily maximum UV index in Grafton is 6. A UV Index estimate of 6 to 7 represents a high health vulnerability from 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 July
Grafton, IL

Average temperature in July - Grafton, IL
  • Average high temperature in July: 86.4°F

The warmest month (with the highest average high temperature) is July (86.4°F).
The month with the lowest average high temperature is January (36.1°F).

  • Average low temperature in July: 68.2°F

The month with the highest average low temperature is July (68.2°F).
The coldest month (with the lowest average low temperature) is January (23.4°F).

Average pressure in July
Grafton, IL

Average pressure in July - Grafton, IL
  • Average pressure in July: 29.97"Hg

The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).

Average wind speed in July
Grafton, IL

Average wind speed in July - Grafton, IL
  • Average wind speed in July: 5.7mph

The windiest month (with the highest average wind speed) is January (9.4mph).
The calmest months (with the lowest average wind speed) are July and August (5.7mph).

Average humidity in July
Grafton, IL

Average humidity in July - Grafton, IL
  • Average humidity in July: 78%

The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (71%).

Average rainfall in July
Grafton, IL

Average rainfall in July - Grafton, IL
  • Average rainfall in July: 2.68"

The wettest month (with the highest rainfall) is May (3.35").
The driest month (with the least rainfall) is February (1.3").

Average rainfall days in July
Grafton, IL

Average rainfall days in July - Grafton, IL
  • Average rainfall days in July: 16.3 days

The month with the highest number of rainy days is July (16.3 days).
The month with the least rainy days is January (6.3 days).

Average snowfall in July
Grafton, IL

Average snowfall in July - Grafton, IL
  • Average snowfall in July: 0"

The months with the highest snowfall are January and February (1.54").
The months with the least snowfall are April, May, June, July, August, September and October (0").

Average snowfall days in July
Grafton, IL

Average snowfall days in July - Grafton, IL
  • Average snowfall days in July: 0 days

The month with the highest number of snowfall days is January (5.7 days).
The months with the least snowfall days are May, June, July, August and September (0 days).

Average daylight in July /
Average sunshine in July
Grafton, IL

Average daylight in July / Average sunshine in July - Grafton, IL
  • Average daylight in July: 14h and 4min

The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).

  • Average sunshine in July: 10h and 2min

The months with the most sunshine are June and July (Average sunshine: 10h and 24min).
The months with the least sunshine are January and February (Average sunshine: 4h and 36min).

Average sunshine days in July
Grafton, IL

Average sunshine days in July - Grafton, IL
  • Average sunshine days in July: 12.7 days

The month with the most sunshine days is December (19.8 days).
The month with the least sunshine days is June (11.2 days).

Average UV index in July
Grafton, IL

Average UV index in July - Grafton, IL
  • Average UV index in July: 6

The months with the highest UV index are May, 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 July
Grafton, IL

Average cloud cover in July - Grafton, IL
  • Average cloud cover in July: 29

The month with the most cloud cover is January (Cloud cover 51).
The month with the least cloud cover is August (Cloud cover 28).

Average visibility in July
Grafton, IL

Average visibility in July - Grafton, IL
  • Average visibility in July: 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).

Grafton, Illinois, USA

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