Average Weather in August in The Dalles Oregon, United States
In The Dalles, the month of August is characterized by falling daily high temperatures, with daily highs decreasing by 5°F, from 89°F to 85°F over the course of the month, and rarely exceeding 101°F or dropping below 74°F. The highest daily average high temperature is 89°F on August 4.
Daily low temperatures decrease by 5°F, from 62°F to 56°F, rarely falling below 49°F or exceeding 68°F. The highest daily average low temperature is 62°F on August 1.
For reference, on August 3, the hottest day of the year, temperatures in The Dalles typically range from 62°F to 89°F, while on January 1, the coldest day of the year, they range from 29°F to 40°F.
Average High and Low Temperature in August
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on August. The horizontal axis is the day, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature in August
The month of August in The Dalles experiences increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 17% to 25%. The lowest chance of overcast or mostly cloudy conditions is 17% on August 3.
The clearest day of the month is August 3, with clear, mostly clear, or partly cloudy conditions 83% of the time.
For reference, on January 14, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 70%, while on August 3, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 83%.
Cloud Cover Categories in August
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In The Dalles, the chance of a wet day over the course of August is increasing, starting the month at 5% and ending it at 9%.
For reference, the year's highest daily chance of a wet day is 52% on November 28, and its lowest chance is 4% on August 5.
Probability of Precipitation in August
The average sliding 31-day rainfall during August in The Dalles is gradually increasing, starting the month at 0.2 inches, when it rarely exceeds 0.7 inches, and ending the month at 0.6 inches, when it rarely exceeds 1.6 inches.
Average Monthly Rainfall in August
Over the course of August in The Dalles, the length of the day is rapidly decreasing. From the start to the end of the month, the length of the day decreases by 1 hour, 25 minutes, implying an average daily decrease of 2 minutes, 50 seconds, and weekly decrease of 19 minutes, 53 seconds.
The shortest day of the month is August 31, with 13 hours, 18 minutes of daylight and the longest day is August 1, with 14 hours, 44 minutes of daylight.
Hours of Daylight and Twilight in August
The earliest sunrise of the month in The Dalles is 5:48 AM on August 1 and the latest sunrise is 36 minutes later at 6:25 AM on August 31.
The latest sunset is 8:32 PM on August 1 and the earliest sunset is 49 minutes earlier at 7:43 PM on August 31.
Daylight saving time is observed in The Dalles during 2017, but it neither starts nor ends during August, so the entire month is in daylight saving time.
For reference, on June 21, the longest day of the year, the Sun rises at 5:15 AM and sets 15 hours, 42 minutes later, at 8:57 PM, while on December 21, the shortest day of the year, it rises at 7:42 AM and sets 8 hours, 41 minutes later, at 4:23 PM.
Sunrise & Sunset with Twilight in August
The chance that a given day will be muggy in The Dalles is essentially constant during August, remaining around 1% throughout.
The highest chance of a muggy day during August is 1% on August 4.
For reference, on August 4, the muggiest day of the year, there are muggy conditions 1% of the time, while on January 1, the least muggy day of the year, there are muggy conditions 0% of the time.
Humidity Comfort Levels in August
The average hourly wind speed in The Dalles is essentially constant during August, remaining within 0.2 miles per hour of 5.6 miles per hour throughout.
For reference, on June 7, the windiest day of the year, the daily average wind speed is 6.5 miles per hour, while on October 7, the calmest day of the year, the daily average wind speed is 5.2 miles per hour.
Average Wind Speed in August
Wind Direction in August
The growing season in The Dalles typically lasts for 6.5 months (199 days), from around April 11 to around October 27, rarely starting before March 22 or after May 3, and rarely ending before October 7 or after November 14.
The month of August in The Dalles is reliably fully within the growing season.
Time Spent in Various Temperature Bands and the Growing Season in August
The average accumulated growing degree days in The Dalles is rapidly increasing during August, increasing by 663°F, from 1,729°F to 2,392°F, over the course of the month.
Growing Degree Days in August
The average daily incident shortwave solar energy in The Dalles is decreasing during August, falling by 1.4 kWh, from 7.4 kWh to 6.0 kWh, over the course of the month.
Average Daily Incident Shortwave Solar Energy in August
For the purposes of this report, the geographical coordinates of The Dalles are 45.595 deg latitude, -121.179 deg longitude, and 446 ft elevation.
The topography within 2 miles of The Dalles contains very significant variations in elevation, with a maximum elevation change of 1,001 feet and an average elevation above sea level of 392 feet. Within 10 miles contains very significant variations in elevation (3,146 feet). Within 50 miles contains large variations in elevation (12,280 feet).
The area within 2 miles of The Dalles is covered by artificial surfaces (51%) and cropland (32%), within 10 miles by shrubs (42%) and grassland (32%), and within 50 miles by shrubs (52%) and trees (34%).
This report illustrates the typical weather in The Dalles year round, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
There are 3 weather stations near enough to contribute to our estimation of the temperature and dew point in The Dalles.
For each station, the records are corrected for the elevation difference between that station and The Dalles according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
The estimated value at The Dalles is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between The Dalles and a given station.
The stations contributing to this reconstruction are: The Dalles Municipal Airport (97%, 2.9 kilometers, north); Portland–Troutdale Airport (1.9%, 96 kilometers, west); and Roberts Field-Redmond Municipal Airport (0.8%, 149 kilometers, south).
Time zones for aiports and weather stations are provided by AskGeo.com .