Average Weather in August in Des Peres Missouri, United States
Daily high temperatures decrease by 3°F, from 88°F to 85°F, rarely falling below 76°F or exceeding 96°F.
Daily low temperatures decrease by 4°F, from 70°F to 66°F, rarely falling below 57°F or exceeding 77°F.
For reference, on July 20, the hottest day of the year, temperatures in Des Peres typically range from 71°F to 89°F, while on January 22, the coldest day of the year, they range from 25°F to 41°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
Qubadlı, Azerbaijan (6,410 miles away); Mahdishahr, Iran (6,813 miles); and Gwangju, South Korea (6,817 miles) are the far-away foreign places with temperatures most similar to Des Peres (view comparison).
The month of August in Des Peres experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 31% throughout the month. The lowest chance of overcast or mostly cloudy conditions is 30% on August 27.
The clearest day of the month is August 27, with clear, mostly clear, or partly cloudy conditions 70% of the time.
For reference, on February 12, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 54%, while on August 27, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 70%.
Cloud Cover Categories in August
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Des Peres, the chance of a wet day over the course of August is decreasing, starting the month at 32% and ending it at 28%.
For reference, the year's highest daily chance of a wet day is 41% on May 21, and its lowest chance is 16% on January 13.
Probability of Precipitation in August
The average sliding 31-day rainfall during August in Des Peres is essentially constant, remaining about 2.9 inches throughout, and rarely exceeding 5.3 inches or falling below 1.0 inches.
The lowest average 31-day accumulation is 2.8 inches on August 3.
Average Monthly Rainfall in August
Over the course of August in Des Peres, 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, 6 minutes, implying an average daily decrease of 2 minutes, 11 seconds, and weekly decrease of 15 minutes, 19 seconds.
The shortest day of the month is August 31, with 13 hours, 3 minutes of daylight and the longest day is August 1, with 14 hours, 9 minutes of daylight.
Hours of Daylight and Twilight in August
The earliest sunrise of the month in Des Peres is 6:03 AM on August 1 and the latest sunrise is 27 minutes later at 6:30 AM on August 31.
The latest sunset is 8:12 PM on August 1 and the earliest sunset is 39 minutes earlier at 7:33 PM on August 31.
Daylight saving time is observed in Des Peres during 2018, 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 5:37 AM and sets 14 hours, 52 minutes later, at 8:29 PM, while on December 21, the shortest day of the year, it rises at 7:15 AM and sets 9 hours, 28 minutes later, at 4:43 PM.
Sunrise & Sunset with Twilight in August
The chance that a given day will be muggy in Des Peres is rapidly decreasing during August, falling from 67% to 49% over the course of the month.
For reference, on July 24, the muggiest day of the year, there are muggy conditions 70% of the time, while on December 19, 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 Des Peres is essentially constant during August, remaining within 0.2 miles per hour of 5.3 miles per hour throughout.
For reference, on February 26, the windiest day of the year, the daily average wind speed is 8.9 miles per hour, while on July 31, the calmest day of the year, the daily average wind speed is 5.1 miles per hour.
The lowest daily average wind speed during August is 5.1 miles per hour on August 3.
Average Wind Speed in August
Wind Direction in August
The growing season in Des Peres typically lasts for 6.9 months (211 days), from around April 4 to around October 31, rarely starting before March 17 or after April 20, and rarely ending before October 14 or after November 17.
The month of August in Des Peres 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 Des Peres are rapidly increasing during August, increasing by 785°F, from 2,527°F to 3,312°F, over the course of the month.
Growing Degree Days in August
The average daily incident shortwave solar energy in Des Peres is gradually decreasing during August, falling by 0.7 kWh, from 6.6 kWh to 5.8 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 Des Peres are 38.601 deg latitude, -90.433 deg longitude, and 597 ft elevation.
The topography within 2 miles of Des Peres contains only modest variations in elevation, with a maximum elevation change of 233 feet and an average elevation above sea level of 596 feet. Within 10 miles also contains only modest variations in elevation (446 feet). Within 50 miles contains only modest variations in elevation (945 feet).
The area within 2 miles of Des Peres is covered by artificial surfaces (75%) and trees (25%), within 10 miles by artificial surfaces (78%) and trees (16%), and within 50 miles by cropland (46%) and trees (39%).
This report illustrates the typical weather in Des Peres 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 4 weather stations near enough to contribute to our estimation of the temperature and dew point in Des Peres.
For each station, the records are corrected for the elevation difference between that station and Des Peres 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 Des Peres is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Des Peres and a given station.
The stations contributing to this reconstruction are: Lambert–St. Louis International Airport (40%, 18 kilometers, north); Spirit of St Louis Airport (32%, 20 kilometers, west); Saint Louis Downtown - Parks Airport (24%, 24 kilometers, east); and Farmington Regional Airport (3.3%, 93 kilometers, south).
Time zones for aiports and weather stations are provided by AskGeo.com .