Average Weather in September in Vian Oklahoma, United States
Daily high temperatures decrease by 11°F, from 90°F to 79°F, rarely falling below 69°F or exceeding 98°F.
Daily low temperatures decrease by 11°F, from 68°F to 57°F, rarely falling below 46°F or exceeding 74°F.
For reference, on July 24, the hottest day of the year, temperatures in Vian typically range from 72°F to 93°F, while on January 7, the coldest day of the year, they range from 30°F to 49°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
’Aïn el Bell, Algeria (5,298 miles away); Kafr Takhārīm, Syria (6,596 miles); and Shahrisabz, Uzbekistan (7,164 miles) are the far-away foreign places with temperatures most similar to Vian (view comparison).
The month of September in Vian 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 clearest day of the month is September 30, with clear, mostly clear, or partly cloudy conditions 70% of the time.
For reference, on February 16, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 49%, while on October 5, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 71%.
Cloud Cover Categories in September
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Vian, the chance of a wet day over the course of September is essentially constant, remaining around 28% throughout.
For reference, the year's highest daily chance of a wet day is 43% on May 21, and its lowest chance is 15% on January 16.
Probability of Precipitation in September
The average sliding 31-day rainfall during September in Vian is increasing, starting the month at 3.3 inches, when it rarely exceeds 6.3 inches or falls below 1.0 inches, and ending the month at 3.9 inches, when it rarely exceeds 7.4 inches or falls below 1.1 inches.
The highest average 31-day accumulation is 4.0 inches on September 21.
Average Monthly Rainfall in September
Over the course of September in Vian, 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, 4 minutes, implying an average daily decrease of 2 minutes, 12 seconds, and weekly decrease of 15 minutes, 23 seconds.
The shortest day of the month is September 30, with 11 hours, 51 minutes of daylight and the longest day is September 1, with 12 hours, 55 minutes of daylight.
Hours of Daylight and Twilight in September
The earliest sunrise of the month in Vian is 6:52 AM on September 1 and the latest sunrise is 22 minutes later at 7:14 AM on September 30.
The latest sunset is 7:46 PM on September 1 and the earliest sunset is 42 minutes earlier at 7:04 PM on September 30.
Daylight saving time is observed in Vian 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 6:04 AM and sets 14 hours, 34 minutes later, at 8:38 PM, while on December 21, the shortest day of the year, it rises at 7:25 AM and sets 9 hours, 45 minutes later, at 5:10 PM.
Sunrise & Sunset with Twilight in September
The chance that a given day will be muggy in Vian is very rapidly decreasing during September, falling from 57% to 18% over the course of the month.
For reference, on July 6, the muggiest day of the year, there are muggy conditions 82% of the time, while on December 13, the least muggy day of the year, there are muggy conditions 0% of the time.
Humidity Comfort Levels in September
The average hourly wind speed in Vian is gradually increasing during September, increasing from 6.1 miles per hour to 6.9 miles per hour over the course of the month.
For reference, on March 19, the windiest day of the year, the daily average wind speed is 9.1 miles per hour, while on August 3, the calmest day of the year, the daily average wind speed is 5.6 miles per hour.
Average Wind Speed in September
Wind Direction in September
The growing season in Vian typically lasts for 7.3 months (223 days), from around March 28 to around November 6, rarely starting before March 6 or after April 17, and rarely ending before October 18 or after November 27.
The month of September in Vian 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 Vian are rapidly increasing during September, increasing by 648°F, from 3,827°F to 4,475°F, over the course of the month.
Growing Degree Days in September
The average daily incident shortwave solar energy in Vian is gradually decreasing during September, falling by 0.9 kWh, from 5.9 kWh to 4.9 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 Vian are 35.498 deg latitude, -94.970 deg longitude, and 564 ft elevation.
The topography within 2 miles of Vian contains only modest variations in elevation, with a maximum elevation change of 397 feet and an average elevation above sea level of 563 feet. Within 10 miles contains only modest variations in elevation (869 feet). Within 50 miles contains very significant variations in elevation (2,211 feet).
The area within 2 miles of Vian is covered by cropland (65%) and trees (31%), within 10 miles by trees (43%) and cropland (40%), and within 50 miles by cropland (46%) and trees (44%).
This report illustrates the typical weather in Vian 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 Vian.
For each station, the records are corrected for the elevation difference between that station and Vian 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 Vian is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Vian and a given station.
The stations contributing to this reconstruction are: Sallisaw Municipal Airport (51%, 17 kilometers, southeast); Stigler Regional Airport (25%, 27 kilometers, southwest); Davis Field Airport (14%, 40 kilometers, northwest); and Tahlequah Municipal Airport (10%, 48 kilometers, north).
Time zones for aiports and weather stations are provided by AskGeo.com .