Flagstaff
Arizona, USA
Long-term weather forecast
Long-term weather forecast

August weather forecast and climate
Flagstaff, AZ

A close-up of the brown iconic clock tower in the city of Flagstaff, Arizona, with the street signs of Birch Avenue and San Francisco Street
A close-up of the brown iconic clock tower in the city of Flagstaff, Arizona, with the street signs of Birch Avenue and San Francisco Street
The last month of the summer, August, is also a moderately hot month in Flagstaff, Arizona, with temperature in the range of an average high of 78.4°F (25.8°C) and an average low of 50.2°F (10.1°C).

Temperature

In August, the average high-temperature is almost the same as in July - a still warm 78.4°F (25.8°C). In Flagstaff, the average low-temperature is 50.2°F (10.1°C).

Humidity

In Flagstaff, the average relative humidity is 58.1%.

Rainfall

August is the month with the most rainfall. Rain falls for 14 days and accumulates 3.1" (79mm) of precipitation.

Snowfall

In Flagstaff snow does not fall in June through September.

Daylight

In August, the average length of the day in Flagstaff, Arizona, is 13.4h.

Sunshine

In August, the average sunshine in Flagstaff is 10.1h.

UV index

In Flagstaff, the average daily maximum UV index is 11. A UV Index value of 11, and more, symbolizes an extreme threat to health from the exposure to the Sun's UV radiation for the ordinary person.
Note: The average daily UV index of 11 in August transform into the following instructions:
Take all necessary precautions, as unprotected skin can burn in minutes. Seek shade and minimize exposure to direct Sun in a period between 10 a.m. and 4 p.m. when UV radiation is most intense; keep in mind that shade structures like parasols or canopies do not provide perfect sun 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.

What is the temperature in August in Flagstaff?

The average high-temperature, in August, is 78.4°F (25.8°C), while the average low-temperature is 50.2°F (10.1°C).

What is the average humidity in August in Flagstaff?

In Flagstaff, the average relative humidity in August is 58.1%.

How many days does it rain in August in Flagstaff?

In Flagstaff, during August, the rain falls for 14 days and regularly aggregates up to 3.1" (79mm) of precipitation.

What is the wettest month in Flagstaff?

August is the month with the most rainfall. Rain falls for 14 days and accumulates 3.1" (79mm) of precipitation.

When it does not snow in Flagstaff?

June through September are months without snowfall.

How many hours of daylight does Flagstaff have in August?

In Flagstaff, Arizona, the average length of the day in August is 13.4h.

How long on average sun shines in August in Flagstaff?

In Flagstaff, the average sunshine in August is 10.1h.

How high is the UV index in August in Flagstaff?

In Flagstaff, the average daily maximum UV index in August is 11. A UV Index reading of 11, and higher, represents an excessive health risk from unsafe exposure to the Sun's UV rays.
Average temperature in August - Flagstaff, AZ
  • Average high temperature in August: 78.4°F

The warmest month (with the highest average high temperature) is July (81.2°F).
Months with the lowest average high temperature are January and December (42.5°F).

  • Average low temperature in August: 50.1°F

The month with the highest average low temperature is July (50.9°F).
The coldest month (with the lowest average low temperature) is December (16.8°F).

Average humidity in August - Flagstaff, AZ
  • Average humidity in August: 58.1%

The month with the highest relative humidity is January (61.9%).
The month with the lowest relative humidity is June (33.6%).

Average rainfall in August - Flagstaff, AZ
  • Average rainfall in August: 3.1"

The wettest month (with the highest rainfall) is August (3.1").
The driest month (with the lowest rainfall) is June (0.4").

Average rainfall days in August - Flagstaff, AZ
  • Average rainfall days in August: 14 days

The month with the highest number of rainy days is August (14 days).
The month with the lowest number of rainy days is June (2.6 days).

Average snowfall in August - Flagstaff, AZ
  • Average snowfall in August: 0"

The month with the highest snowfall is January (23.2").
Months with the lowest snowfall are June, July, August and September (0").

Average snowfall days in August - Flagstaff, AZ
  • Average snowfall days in August: 0 days

The month with the highest number of snowfall days is January (7.5 days).
Months with the lowest number of snowfall days are June, July, August and September (0 days).

Average daylight in August / Average sunshine in August - Flagstaff, AZ
  • Average daylight in August: 13.4h

The month with the longest days is June (Average daylight: 14.5h).
The month with shortest days is December (Average daylight: 9.8h).

  • Average sunshine in August: 10.1h

The month with most sunshine is June (Average sunshine: 12.4h).
The month with least sunshine is December (Average sunshine: 7.1h).

Average UV index in August - Flagstaff, AZ
  • Average UV index in August: 11

The month with the highest UV index is July (UV index 12).
Months with the lowest UV index are January and December (UV index 3).