Average Weather in September at Jackson Hole Airport Wyoming, United States
At Jackson Hole Airport, the month of September is characterized by rapidly falling daily high temperatures, with daily highs decreasing by 12°F, from 74°F to 62°F over the course of the month, and rarely exceeding 82°F or dropping below 48°F.
Daily low temperatures decrease by 8°F, from 39°F to 32°F, rarely falling below 23°F or exceeding 48°F.
For reference, on July 28, the hottest day of the year, temperatures at Jackson Hole Airport typically range from 44°F to 80°F, while on January 27, the coldest day of the year, they range from 6°F to 25°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 at Jackson Hole Airport experiences gradually increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 28% to 34%.
The clearest day of the month is September 1, with clear, mostly clear, or partly cloudy conditions 72% of the time.
For reference, on March 18, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 58%, while on July 28, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 78%.
Cloud Cover in September
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. At Jackson Hole Airport, the chance of a wet day over the course of September is gradually increasing, starting the month at 17% and ending it at 19%.
For reference, the year's highest daily chance of a wet day is 32% on May 30, and its lowest chance is 14% on July 4.
Over the course of September at Jackson Hole Airport, the chance of a day with only rain remains an essentially constant 17% throughout, the chance of a day with mixed snow and rain remains an essentially constant 1% throughout, and the chance of a day with only snow remains an essentially constant 0% throughout.
Probability of Precipitation in September
To show variation within the month and not just the monthly total, we show the rainfall accumulated over a sliding 31-day period centered around each day.
The average sliding 31-day rainfall during September at Jackson Hole Airport is essentially constant, remaining about 1.0 inches throughout, and rarely exceeding 2.4 inches or falling below 0.1 inches.
Average Monthly Rainfall in September
Over the course of September at Jackson Hole Airport, 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, 56 seconds, and weekly decrease of 20 minutes, 35 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, 11 minutes of daylight.
Hours of Daylight and Twilight in September
The earliest sunrise of the month at Jackson Hole Airport is 6:47 AM on September 1 and the latest sunrise is 33 minutes later at 7:19 AM on September 30.
The latest sunset is 7:57 PM on September 1 and the earliest sunset is 53 minutes earlier at 7:05 PM on September 30.
Daylight saving time is observed at Jackson Hole Airport during 2017, 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 5:41 AM and sets 15 hours, 26 minutes later, at 9:08 PM, while on December 21, the shortest day of the year, it rises at 7:53 AM and sets 8 hours, 56 minutes later, at 4:49 PM.
Sunrise & Sunset with Twilight in September
We base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night.
The chance that a given day will be muggy at Jackson Hole Airport is essentially constant during September, remaining around 0% throughout.
Humidity Comfort Levels in September
This section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages.
The average hourly wind speed at Jackson Hole Airport is essentially constant during September, remaining around 2.6 miles per hour throughout.
For reference, on March 30, the windiest day of the year, the daily average wind speed is 2.9 miles per hour, while on August 4, the calmest day of the year, the daily average wind speed is 2.5 miles per hour.
The highest daily average wind speed during September is 2.6 miles per hour on September 6.
Average Wind Speed in September
Wind Direction in September
This section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation.
The average daily incident shortwave solar energy at Jackson Hole Airport is rapidly decreasing during September, falling by 1.5 kWh, from 6.2 kWh to 4.7 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 Jackson Hole Airport are 43.607 deg latitude, -110.739 deg longitude, and 6,424 ft elevation.
The topography within 2 miles of Jackson Hole Airport contains only modest variations in elevation, with a maximum elevation change of 259 feet and an average elevation above sea level of 6,426 feet. Within 10 miles contains only modest variations in elevation (7,500 feet). Within 50 miles also contains extreme variations in elevation (8,691 feet).
The area within 2 miles of Jackson Hole Airport is covered by shrubs (82%) and grassland (13%), within 10 miles by shrubs (54%) and trees (20%), and within 50 miles by trees (43%) and shrubs (39%).
This report illustrates the typical weather at Jackson Hole Airport 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
Jackson Hole Airport has a weather station that reported reliably enough during the analysis period that we have included it in our network. When available, historical temperature and dew point measurements are taken directly from this weather station. These records are obtained from NOAA's Integrated Surface Hourly data set, falling back on ICAO METAR records as required.
In the case of missing or erroneous measurements from this station, we fall back on records from nearby stations, adjusted according to typical seasonal and diurnal intra-station differences. For a given day of the year and hour of the day, the fallback station is selected to minimize the prediction error over the years for which there are measurements for both stations.
The stations on which we may fall back include but are not limited to Driggs, Driggs-Reed Memorial Airport; West Yellowstone; Rexburg Airport; Big Piney-Marbleton Airport; Ralph Wenz Field; Fanning Field; Yellowstone Regional Airport; and Pocatello Regional Airport.
All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Tables of the Sun, Moon and Planets , by Jean Meeus.
All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid.
Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations.
Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory.
Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database .
Time zones for aiports and weather stations are provided by AskGeo.com .
Maps are © Esri, with data from National Geographic, Esri, DeLorme, NAVTEQ, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, and iPC.