Average Weather in September in Jacksonville Alabama, United States
In Jacksonville, the month of September is characterized by falling daily high temperatures, with daily highs decreasing by 8°F, from 87°F to 79°F over the course of the month, and rarely exceeding 93°F or dropping below 70°F.
Daily low temperatures decrease by 10°F, from 67°F to 58°F, rarely falling below 46°F or exceeding 72°F.
For reference, on July 22, the hottest day of the year, temperatures in Jacksonville typically range from 70°F to 89°F, while on January 26, the coldest day of the year, they range from 34°F to 53°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 Jacksonville experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 35% throughout the month.
The clearest day of the month is September 21, with clear, mostly clear, or partly cloudy conditions 67% of the time.
For reference, on January 4, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 55%, while on October 13, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 67%.
Cloud Cover Categories in September
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Jacksonville, the chance of a wet day over the course of September is decreasing, starting the month at 27% and ending it at 22%.
For reference, the year's highest daily chance of a wet day is 44% on July 9, and its lowest chance is 21% on October 15.
Probability of Precipitation in September
The average sliding 31-day rainfall during September in Jacksonville is gradually increasing, starting the month at 2.8 inches, when it rarely exceeds 5.8 inches or falls below 0.9 inches, and ending the month at 3.1 inches, when it rarely exceeds 6.6 inches or falls below 0.7 inches.
The highest average 31-day accumulation is 3.2 inches on September 23.
Average Monthly Rainfall in September
Over the course of September in Jacksonville, the length of the day is decreasing. From the start to the end of the month, the length of the day decreases by 60 minutes, implying an average daily decrease of 2 minutes, 4 seconds, and weekly decrease of 14 minutes, 28 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, 51 minutes of daylight.
Hours of Daylight and Twilight in September
The earliest sunrise of the month in Jacksonville is 6:17 AM on September 1 and the latest sunrise is 20 minutes later at 6:36 AM on September 30.
The latest sunset is 7:08 PM on September 1 and the earliest sunset is 40 minutes earlier at 6:28 PM on September 30.
Daylight saving time is observed in Jacksonville 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 5:32 AM and sets 14 hours, 24 minutes later, at 7:57 PM, while on December 21, the shortest day of the year, it rises at 6:44 AM and sets 9 hours, 54 minutes later, at 4:38 PM.
Sunrise & Sunset with Twilight in September
The chance that a given day will be muggy in Jacksonville is very rapidly decreasing during September, falling from 68% to 21% over the course of the month.
For reference, on July 22, the muggiest day of the year, there are muggy conditions 90% of the time, while on January 23, 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 Jacksonville is gradually increasing during September, increasing from 3.5 miles per hour to 4.1 miles per hour over the course of the month.
For reference, on February 26, the windiest day of the year, the daily average wind speed is 5.3 miles per hour, while on August 4, the calmest day of the year, the daily average wind speed is 3.2 miles per hour.
Average Wind Speed in September
Wind Direction in September
The growing season in Jacksonville typically lasts for 7.3 months (225 days), from around March 28 to around November 7, rarely starting before March 5 or after April 18, and rarely ending before October 20 or after November 28.
The month of September in Jacksonville 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 Jacksonville is rapidly increasing during September, increasing by 630°F, from 3,722°F to 4,352°F, over the course of the month.
Growing Degree Days in September
The average daily incident shortwave solar energy in Jacksonville is gradually decreasing during September, falling by 0.8 kWh, from 5.8 kWh to 5.0 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 Jacksonville are 33.814 deg latitude, -85.761 deg longitude, and 719 ft elevation.
The topography within 2 miles of Jacksonville contains very significant variations in elevation, with a maximum elevation change of 981 feet and an average elevation above sea level of 764 feet. Within 10 miles also contains very significant variations in elevation (1,555 feet). Within 50 miles contains very significant variations in elevation (2,005 feet).
The area within 2 miles of Jacksonville is covered by trees (50%), artificial surfaces (38%), and cropland (12%), within 10 miles by trees (74%) and cropland (19%), and within 50 miles by trees (67%) and cropland (25%).
This report illustrates the typical weather in Jacksonville 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 5 weather stations near enough to contribute to our estimation of the temperature and dew point in Jacksonville.
For each station, the records are corrected for the elevation difference between that station and Jacksonville 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 Jacksonville is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Jacksonville and a given station.
The stations contributing to this reconstruction are: Anniston Metropolitan Airport (42%, 27 kilometers, south); Northeast Alabama Regional Airport (29%, 34 kilometers, northwest); West Georgia Regional Airport - O V Gray Field (12%, 60 kilometers, east); Isbell Field (9%, 74 kilometers, north); and Richard B Russell Airport (8%, 81 kilometers, northeast).
Time zones for aiports and weather stations are provided by AskGeo.com .