August weather forecast
Grand Canyon National Park, AZ

Grand Canyon National Park witnesses a slight decrease in temperature in August. Despite this, it remains quite hot with peaks at 100°F (37.8°C). Marked increase in rainfall to 1.5" (38mm) hints at the onset of the rainy season. Although the daylight hours decrease slightly as compared to the preceding months, August promises ample sun-kissed hours for park visitors. Be prepared for possible rain showers during your expedition in this month.

Temperature

Grand Canyon National Park observes a minor difference in average high-temperatures between July's 104°F (40°C) and August's 100°F (37.8°C). Grand Canyon National Park records a marked daily temperature contrast, with an average low-temperature of 72°F (22.2°C) during the nights of August.

Rainfall

August is the month with the most rainfall. Rain falls for 5 days and accumulates 1.46" (37mm) of precipitation.

Snowfall

February through November are months without snowfall in Grand Canyon National Park.

Daylight

The average length of the day in August in Grand Canyon National Park is 13h and 29min.
On the first day of August, sunrise is at 5:36 am and sunset at 7:33 pm. On the last day of the month, sunrise is at 6:00 am and sunset at 6:57 pm MST.

Sunshine

The average sunshine in August is 11h.

UV index

The average daily maximum UV index in August in Grand Canyon National Park is 10. A UV Index reading of 8 to 10 represents a very high health vulnerability from exposure to the Sun's UV radiation for ordinary individuals.
Note: The maximum daily UV index of 10 in August interprets into the following recommendations:
Precautions are essential; the risk of damage to unprotected skin and eyes is too high. Between 10 a.m. and 4 p.m., the Sun emits the most powerful UV radiation. Limit direct exposure to the Sun during these hours. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim. Directly after outdoor activities or swimming, a broad-spectrum sunscreen with SPF 30+ should be applied generously and reapplied frequently.