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
Grand Coulee marks the onset of August with an average high-temperature of a still warm 84.2°F (29°C), subtly divergent from July's 84.9°F (29.4°C). Contrasted against daytime highs, Grand Coulee records an average nighttime low of 61.3°F (16.3°C) in August.Humidity
With an average relative humidity of 36%, August is the least humid month.Rainfall
July and August are months with the least rain when the rain falls for 3.2 days and typically aggregates up to 0.2" (5mm) of rain.Snowfall
In Grand Coulee, snow does not fall in May through August.Daylight
In Grand Coulee, the average length of the day in August is 14h and 14min.On the first day of the month, sunrise is at 5:33 am and sunset at 8:31 pm. On the last day of August, sunrise is at 6:14 am and sunset at 7:38 pm PDT.
Sunshine
With an average of 12.1h of sunshine, August has the most sunshine of the year.UV index
In August, the average daily maximum UV index is 5. A UV Index value of 3 to 5 symbolizes a medium health hazard from unprotected exposure to Sun's UV rays for the average person.Note: A maximum UV index of 5 in August translates into the following recommendations:
Heed the precautions - Suggestions to avoid sunburn are made. To avoid the Sun's strongest rays, limit exposure around the mid-day period. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is August?
What is the least humid month?
What is the average humidity in August in Grand Coulee?
What is the driest month?
How much does it rain in Grand Coulee in August?
When it does not snow?
Does it snow in August?
How many hours of daylight does Grand Coulee have in August?
When are sunrise and sunset in August?
What month has the most sunshine?
How long on average sun shines in August?
What is the UV index intensity in August?
Average temperature in August
Grand Coulee, WA
- Average high temperature in August: 84.2°F
The warmest month (with the highest average high temperature) is July (84.9°F).
The month with the lowest average high temperature is December (31.6°F).
- Average low temperature in August: 61.3°F
The month with the highest average low temperature is August (61.3°F).
The coldest month (with the lowest average low temperature) is December (21.4°F).
Average pressure in August
Grand Coulee, WA
- Average pressure in August: 29.91"Hg
The month with the highest atmospheric pressure is January (30.18"Hg).
The month with the lowest atmospheric pressure is August (29.91"Hg).
Average wind speed in August
Grand Coulee, WA
- Average wind speed in August: 5.7mph
The windiest month (with the highest average wind speed) is April (7mph).
The calmest month (with the lowest average wind speed) is January (4.9mph).
Average humidity in August
Grand Coulee, WA
- Average humidity in August: 36%
The month with the highest relative humidity is January (89%).
The month with the lowest relative humidity is August (36%).
Average rainfall in August
Grand Coulee, WA
- Average rainfall in August: 0.2"
The wettest months (with the highest rainfall) are May and December (1.18").
The driest months (with the least rainfall) are July and August (0.2").
Average rainfall days in August
Grand Coulee, WA
- Average rainfall days in August: 3.2 days
The month with the highest number of rainy days is March (12.1 days).
The month with the least rainy days is August (3.2 days).
Average snowfall in August
Grand Coulee, WA
- Average snowfall in August: 0"
The month with the highest snowfall is January (4.41").
The months with the least snowfall are May, June, July and August (0").
Average snowfall days in August
Grand Coulee, WA
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is December (10.5 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight in August /
Average sunshine in August
Grand Coulee, WA
- Average daylight in August: 14h and 1min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in August: 12h and 1min
The month with the most sunshine is August (Average sunshine: 12h and 6min).
The month with the least sunshine is January (Average sunshine: 4h and 6min).
Average sunshine days in August
Grand Coulee, WA
- Average sunshine days in August: 25.8 days
The month with the most sunshine days is August (25.8 days).
The month with the least sunshine days is March (14.7 days).
Average UV index in August
Grand Coulee, WA
- Average UV index in August: 5
The month with the highest UV index is July (UV index 7).
The month with the lowest UV index is November (UV index 1).
Average cloud cover in August
Grand Coulee, WA
- Average cloud cover in August: 12
The month with the most cloud cover is January (Cloud cover 55).
The months with the least cloud cover are July and August (Cloud cover 12).
Average visibility in August
Grand Coulee, WA
- Average visibility in August: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January and December (4mi).
Grand Coulee, Washington, USA
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