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Average Weather in August in Jacksonville Alabama, United States

In Jacksonville, the month of August is characterized by essentially constant daily high temperatures, with daily highs around 88°F throughout the month, rarely exceeding 95°F or dropping below 81°F.

Daily low temperatures decrease by 2°F, from 70°F to 67°F, rarely falling below 61°F or exceeding 73°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 August

The daily average high (red line) and low (blue line) temperature, with 25th to 75th and 10th to 90th percentile bands. The thin dotted lines are the corresponding average perceived temperatures.

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

Average Hourly Temperature in August in Jacksonville12 AM4 AM8 AM12 PM4 PM8 PM12 AM181522291122334455667788991010111112121313141415151616171718181919202021212222232324242525262627272828292930303131JulSepcoolcomfortablewarmhot
The average hourly temperature, color coded into bands: frigid < 15°F < freezing < 32°F < chilly < 45°F < cold < 55°F < cool < 65°F < comfortable < 75°F < warm < 85°F < hot < 95°F < sweltering. The shaded overlays indicate night and civil twilight.


The month of August in Jacksonville experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 37% throughout the month.

The clearest day of the month is August 12, with clear, mostly clear, or partly cloudy conditions 65% 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 in August

The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds: clear < 20% < mostly clear < 40% < partly cloudy < 60% < mostly cloudy < 80% < overcast.


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 August is very rapidly decreasing, starting the month at 37% and ending it at 28%.

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 August

The percentage of days in which various types of precipitation are observed, excluding trace quantities: rain alone, snow alone, and mixed (both rain and snow fell in the same day).


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 August in Jacksonville is essentially constant, remaining about 2.8 inches throughout, and rarely exceeding 5.7 inches or falling below 0.9 inches.

The lowest average 31-day accumulation is 2.7 inches on August 22.

Average Monthly Rainfall in August

The average rainfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average liquid-equivalent snowfall.


Over the course of August 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 55 minutes, implying an average daily decrease of 1 minute, 50 seconds, and weekly decrease of 12 minutes, 48 seconds.

The shortest day of the month is August 31, with 12 hours, 53 minutes of daylight and the longest day is August 1, with 13 hours, 48 minutes of daylight.

Hours of Daylight and Twilight in August

The number of hours during which the Sun is visible (black line). From bottom (most yellow) to top (most gray), the color bands indicate: full daylight, twilight (civil, nautical, and astronomical), and full night.

The earliest sunrise of the month in Jacksonville is 5:55 AM on August 1 and the latest sunrise is 21 minutes later at 6:16 AM on August 31.

The latest sunset is 7:43 PM on August 1 and the earliest sunset is 34 minutes earlier at 7:09 PM on August 31.

Daylight saving time is observed in Jacksonville during 2017, 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 5:32 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 August

The solar day over the course of August. From bottom to top, the black lines are the previous solar midnight, sunrise, solar noon, sunset, and the next solar midnight. The day, twilights (civil, nautical, and astronomical), and night are indicated by the color bands from yellow to gray.


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 in Jacksonville is rapidly decreasing during August, falling from 87% to 69% 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 August

Humidity Comfort Levels in August in Jacksonville0%10%20%30%40%50%60%70%80%90%100%181522291122334455667788991010111112121313141415151616171718181919202021212222232324242525262627272828292930303131JulSepAug 187%Aug 187%Aug 3169%Aug 3169%Aug 1184%Aug 1184%Aug 2179%Aug 2179%oppressiveoppressivemuggymuggyhumidhumidcomfortablecomfortabledrydrymiserablemiserable
The percentage of time spent at various humidity comfort levels, categorized by dew point: dry < 55°F < comfortable < 60°F < humid < 65°F < muggy < 70°F < oppressive < 75°F < miserable.


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 in Jacksonville is essentially constant during August, remaining within 0.1 miles per hour of 1.8 miles per hour throughout.

For reference, on February 26, 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 1.7 miles per hour.

The lowest daily average wind speed during August is 1.7 miles per hour on August 5.

Average Wind Speed in August

The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.
The wind direction in Jacksonville during August is predominantly out of the west from August 1 to August 11 and the east from August 11 to August 31.

Wind Direction in August

Wind Direction in August in JacksonvilleWE0%20%40%60%80%100%181522291122334455667788991010111112121313141415151616171718181919202021212222232324242525262627272828292930303131JulSepwestsoutheastnorth
The percentage of hours in which the mean wind direction is from each of the four cardinal wind directions (north, east, south, and west), excluding hours in which the mean wind speed is less than 1 mph. The lightly tinted areas at the boundaries are the percentage of hours spent in the implied intermediate directions (northeast, southeast, southwest, and northwest).

Solar Energy

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 in Jacksonville is gradually decreasing during August, falling by 0.6 kWh, from 6.4 kWh to 5.8 kWh, over the course of the month.

Average Daily Incident Shortwave Solar Energy in August

The average daily shortwave solar energy reaching the ground per square meter (orange line), with 25th to 75th and 10th to 90th percentile bands.


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%).

Data Sources

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).

Other Data

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.