Average Weather in September in Damascus Oregon, United States
Daily high temperatures decrease by 10°F, from 80°F to 71°F, rarely falling below 60°F or exceeding 91°F.
Daily low temperatures decrease by 5°F, from 54°F to 49°F, rarely falling below 42°F or exceeding 60°F.
For reference, on August 4, the hottest day of the year, temperatures in Damascus typically range from 56°F to 84°F, while on December 30, the coldest day of the year, they range from 35°F to 43°F.
Average High and Low Temperature in September
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on September. 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 September
The month of September in Damascus experiences rapidly increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 28% to 43%.
The clearest day of the month is September 1, with clear, mostly clear, or partly cloudy conditions 72% of the time.
For reference, on November 30, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 76%, while on August 3, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 81%.
Cloud Cover Categories in September
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Damascus, the chance of a wet day over the course of September is very rapidly increasing, starting the month at 12% and ending it at 25%.
For reference, the year's highest daily chance of a wet day is 59% on November 27, and its lowest chance is 5% on August 5.
Probability of Precipitation in September
The average sliding 31-day rainfall during September in Damascus is rapidly increasing, starting the month at 1.1 inches, when it rarely exceeds 2.4 inches or falls below 0.1 inches, and ending the month at 2.7 inches, when it rarely exceeds 5.6 inches or falls below 0.5 inches.
Average Monthly Rainfall in September
Over the course of September in Damascus, 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, 31 minutes, implying an average daily decrease of 3 minutes, 8 seconds, and weekly decrease of 21 minutes, 56 seconds.
The shortest day of the month is September 30, with 11 hours, 45 minutes of daylight and the longest day is September 1, with 13 hours, 16 minutes of daylight.
Hours of Daylight and Twilight in September
The earliest sunrise of the month in Damascus is 6:31 AM on September 1 and the latest sunrise is 35 minutes later at 7:06 AM on September 30.
The latest sunset is 7:47 PM on September 1 and the earliest sunset is 55 minutes earlier at 6:51 PM on September 30.
Daylight saving time is observed in Damascus during 2018, but it neither starts nor ends during September, so the entire month is in daylight saving time.
For reference, on June 21, the longest day of the year, the Sun rises at 5:21 AM and sets 15 hours, 40 minutes later, at 9:01 PM, while on December 21, the shortest day of the year, it rises at 7:46 AM and sets 8 hours, 43 minutes later, at 4:29 PM.
Sunrise & Sunset with Twilight in September
The chance that a given day will be muggy in Damascus is essentially constant during September, remaining around 0% throughout.
For reference, on August 3, the muggiest day of the year, there are muggy conditions 0% 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 September
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The average hourly wind speed in Damascus is essentially constant during September, remaining within 0.2 miles per hour of 4.4 miles per hour throughout.
For reference, on December 3, the windiest day of the year, the daily average wind speed is 6.4 miles per hour, while on August 1, the calmest day of the year, the daily average wind speed is 4.1 miles per hour.
Average Wind Speed in September
Wind Direction in September
The growing season in Damascus typically lasts for 7.7 months (235 days), from around March 24 to around November 13, rarely starting before February 21 or after April 19, and rarely ending before October 21 or after December 12.
The month of September in Damascus is reliably fully within the growing season.
Time Spent in Various Temperature Bands and the Growing Season in September
The average accumulated growing degree days in Damascus are increasing during September, increasing by 352°F, from 1,758°F to 2,110°F, over the course of the month.
Growing Degree Days in September
The average daily incident shortwave solar energy in Damascus is rapidly decreasing during September, falling by 1.8 kWh, from 5.6 kWh to 3.8 kWh, over the course of the month.
Average Daily Incident Shortwave Solar Energy in September
For the purposes of this report, the geographical coordinates of Damascus are 45.418 deg latitude, -122.459 deg longitude, and 466 ft elevation.
The topography within 2 miles of Damascus contains significant variations in elevation, with a maximum elevation change of 774 feet and an average elevation above sea level of 510 feet. Within 10 miles contains significant variations in elevation (1,129 feet). Within 50 miles contains very significant variations in elevation (11,155 feet).
The area within 2 miles of Damascus is covered by cropland (57%), artificial surfaces (26%), and trees (16%), within 10 miles by artificial surfaces (45%) and cropland (29%), and within 50 miles by trees (49%) and cropland (20%).
This report illustrates the typical weather in Damascus 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 Damascus.
For each station, the records are corrected for the elevation difference between that station and Damascus 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 Damascus is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Damascus and a given station.
The stations contributing to this reconstruction are: Portland–Troutdale Airport (65%, 15 kilometers, north); Aurora State Airport (33%, 31 kilometers, southwest); and Roberts Field-Redmond Municipal Airport (2.4%, 166 kilometers, southeast).
Time zones for aiports and weather stations are provided by AskGeo.com .