August weather forecastMattawa, WA
August
Weather in August
The last month of the summer, August, is another hot month in Mattawa, Washington, with an average temperature fluctuating between 88.3°F (31.3°C) and 61.5°F (16.4°C).Temperature
Mattawa's highest average temperatures are recorded in July and August, reaching a high of 88.3°F (31.3°C).Humidity
In Mattawa, Washington, the average relative humidity in August is 38%.Rainfall
The month with the least rainfall is August, when the rain falls for 3.5 days and typically collects 0.2" (5mm) of precipitation.Snowfall
In Mattawa, snow does not fall in May through August and October.Daylight
The average length of the day in August is 14h and 8min.On the first day of the month, sunrise is at 5:40 am and sunset at 8:30 pm. On the last day of August, sunrise is at 6:19 am and sunset at 7:40 pm PDT.
Sunshine
July and August, with an average of 12h of sunshine, are months with the most sunshine.UV index
In Mattawa, the average daily maximum UV index in August is 6. A UV Index reading of 6 to 7 represents a high health risk from exposure to the Sun's UV radiation for ordinary individuals.Note: The UV index of 6 during August leads to these advisories:
Embrace precautions and observe sun safety norms. Evasion of sunburn is a necessity. Stay in the shade and avoid direct Sun exposure from 10 a.m. to 4 p.m., a period when UV radiation is particularly strong, noting that parasols or canopies may not offer total sun protection. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
Mattawa, WA
- Average high temperature in August: 88.3°F
The warmest months (with the highest average high temperature) are July and August (88.3°F).
The month with the lowest average high temperature is December (34.5°F).
- Average low temperature in August: 61.5°F
The month with the highest average low temperature is August (61.5°F).
The coldest month (with the lowest average low temperature) is December (24.3°F).
Average pressure in August
Mattawa, WA
- Average pressure in August: 29.91"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is August (29.91"Hg).
Average wind speed in August
Mattawa, WA
- Average wind speed in August: 6.4mph
The windiest month (with the highest average wind speed) is April (7.6mph).
The calmest month (with the lowest average wind speed) is December (4.7mph).
Average humidity in August
Mattawa, WA
- Average humidity in August: 38%
The month with the highest relative humidity is January (83%).
The month with the lowest relative humidity is July (37%).
Average rainfall in August
Mattawa, WA
- Average rainfall in August: 0.2"
The wettest months (with the highest rainfall) are January and December (0.87").
The driest month (with the least rainfall) is August (0.2").
Average rainfall days in August
Mattawa, WA
- Average rainfall days in August: 3.5 days
The month with the highest number of rainy days is March (10.6 days).
The month with the least rainy days is August (3.5 days).
Average snowfall in August
Mattawa, WA
- Average snowfall in August: 0"
The month with the highest snowfall is December (3.43").
The months with the least snowfall are May, June, July, August and October (0").
Average snowfall days in August
Mattawa, WA
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is December (6.5 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight in August /
Average sunshine in August
Mattawa, WA
- Average daylight in August: 14h and 6min
The month with the longest days is June (Average daylight: 15h and 48min).
The month with the shortest days is December (Average daylight: 8h and 36min).
- Average sunshine in August: 12h and 0min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The month with the least sunshine is January (Average sunshine: 4h and 54min).
Average sunshine days in August
Mattawa, WA
- Average sunshine days in August: 25.8 days
The months with the most sunshine days are July and August (25.8 days).
The month with the least sunshine days is February (16 days).
Average UV index in August
Mattawa, WA
- Average UV index in August: 6
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in August
Mattawa, WA
- Average cloud cover in August: 10
The month with the most cloud cover is January (Cloud cover 47).
The months with the least cloud cover are July and August (Cloud cover 10).
Average visibility in August
Mattawa, WA
- Average visibility in August: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January and December (5mi).
