Climate Jacksonville - Illinois
Jan Ja Feb Fe Mar Ma Apr Ap May Ma Jun Ju Average high in ºF Av. high Hi 35 41 52 65 74 83 Average low in ºF Av. low Lo 17 20 29 40 50 59 Av. precipitation in inch Av. precip. Pre. 1.59 1.69 2.72 4.03 4.81 4.58 Av. snowfall in inch Snowfall Sn 5 5 2 0 0 0
Jul Ju Aug Au Sep Se Oct Oc Nov No Dec De Average high in ºF Av. high Hi 86 85 79 67 53 39 Average low in ºF Av. low Lo 63 61 52 41 32 21 Av. precipitation in inch Av. precip. Pre. 3.95 3.42 3.53 3.01 3.62 2.50 Av. snowfall in inch Snowfall Sn 0 0 0 0 1 5
What is the average weather in Jacksonville, Illinois? Jacksonville experiences a humid continental climate, marked by a very large seasonal temperature contrast. Summers are warm, while winters are cold and bring regular snowfall. The area is fairly wet overall, with precipitation spread relatively evenly throughout the year, though summer tends to be wetter and winter drier.
January February March April May June July August September October November December
1 Jan 36.9 19.7 0.08 0.08 0.10 0.10 2 Jan 36.7 19.6 0.16 0.16 0.30 0.30 3 Jan 36.5 19.4 0.23 0.23 0.40 0.40 4 Jan 36.4 19.2 0.31 0.31 0.60 0.60 5 Jan 36.2 19.0 0.38 0.38 0.70 0.70 6 Jan 36.1 18.9 0.46 0.46 0.90 0.90 7 Jan 36.0 18.7 0.53 0.53 1.00 1.00 8 Jan 35.9 18.5 0.60 0.60 1.20 1.20 9 Jan 35.8 18.4 0.67 0.67 1.30 1.30 10 Jan 35.7 18.3 0.74 0.74 1.50 1.50 11 Jan 35.6 18.1 0.81 0.81 1.60 1.60 12 Jan 35.6 18.0 0.87 0.87 1.80 1.80 13 Jan 35.5 17.9 0.93 0.93 1.90 1.90 14 Jan 35.5 17.8 1.00 1.00 2.10 2.10 15 Jan 35.5 17.7 1.06 1.06 2.30 2.30 16 Jan 35.5 17.6 1.12 1.12 2.40 2.40 17 Jan 35.5 17.6 1.19 1.19 2.60 2.60 18 Jan 35.5 17.5 1.25 1.25 2.80 2.80 19 Jan 35.5 17.5 1.31 1.31 3.00 3.00 20 Jan 35.6 17.5 1.37 1.37 3.20 3.20 21 Jan 35.6 17.4 1.42 1.42 3.40 3.40 22 Jan 35.7 17.4 1.48 1.48 3.60 3.60 23 Jan 35.8 17.5 1.53 1.53 3.70 3.70 24 Jan 35.9 17.5 1.58 1.58 3.90 3.90 25 Jan 36.0 17.5 1.64 1.64 4.10 4.10 26 Jan 36.2 17.6 1.69 1.69 4.30 4.30 27 Jan 36.3 17.7 1.74 1.74 4.40 4.40 28 Jan 36.5 17.7 1.78 1.78 4.60 4.60 29 Jan 36.6 17.8 1.83 1.83 4.80 4.80 30 Jan 36.8 17.9 1.88 1.88 4.90 4.90 31 Jan 37.0 18.1 1.93 1.93 5.10 5.10
Weather history Jacksonville - August 2026
Day 01 Aug 80.1 66.0 0.32 - - 02 Aug 77.0 64.0 0.14 0.00 0.0 03 Aug 82.0 60.1 0.00 0.00 0.0 04 Aug 84.9 60.1 0.00 0.00 0.0 05 Aug 88.0 60.1 0.00 0.00 0.0 06 Aug 82.9 68.0 0.12 0.00 0.0 07 Aug 79.0 66.0 0.13 0.00 0.0 08 Aug 88.0 68.0 0.00 0.00 0.0 09 Aug 90.0 70.0 T 0.00 0.0 10 Aug 91.0 73.0 0.00 0.00 0.0 11 Aug 91.9 73.9 0.00 0.00 0.0 12 Aug - - - - - 13 Aug - - - - - 14 Aug - - - - - 15 Aug - - - - - 16 Aug - - - - - 17 Aug - - - - - 18 Aug - - - - - 19 Aug - - - - - 20 Aug - - - - - 21 Aug - - - - - 22 Aug - - - - - 23 Aug - - - - - 24 Aug - - - - - 25 Aug - - - - - 26 Aug - - - - - 27 Aug - - - - - 28 Aug - - - - - 29 Aug - - - - - 30 Aug - - - - - 31 Aug - - - - -
Past weather Jacksonville
Aug 26 Normal Average high temperature Av. high temp. 85.0 ºF 35 ºF Average low temperature Av. low temp. 66.3 ºF 17 ºF Total precipitation Total precip. 0.71 inch 1.59 inch Total snowfall Total snowfall - inch 5 inch Highest max temperature Highest max temp. 91.9 ºF - Lowest max temperature Lowest max temp. 77.0 ºF - Highest min temperature Highest min temp. 73.9 ºF - Lowest min temperature Lowest min temp. 60.1 ºF -
× Past weather August 2026 incomplete - Missing data
Geo Jacksonville - Illinois
Country United States State Illinois County Morgan City Jacksonville Zip Code 62650 Longitude -90.24 dec. degr. Latitude 39.77 dec. degr. Altitude - Elevation
617ft ICAO - IATA -
Date and Time Jacksonville - Illinois
Local Time 03:30 PM Sunrise 06:10 AM Sunset 08:01 PM Day/Night Day Timezone Central Daylight Time Timezone DB America - Chicago
Map of Jacksonville - Illinois