Weather for Alton, Illinois
Current Weather
Humidity: 82%
Feels Like: 66.9°F
Wind: NE 6.7 mph
Wind Gusts: 14.1 mph
Precipitation: 0 in
Cloud Cover: 0%
Visibility: 9 mi
UV Index: 0
Five Day Weather Forecast
Sun
H: 84°F
L: 57°F
Mon
H: 80°F
L: 59°F
Tue
H: 82°F
L: 70°F
Wed
H: 86°F
L: 68°F
Thu
H: 87°F
L: 69°F
Air Quality
Nitrogen Dioxide: 38.48 μg/m3
Sulphur Dioxide: 5.37 μg/m3
Ozone: 45 μg/m3
Astronomical
Sun Transit: 1:06 PM
Sunset: 8:09 PM
Daylight: 14 hrs 6 mins
Moon Transit: 8:38 PM
Moonset: 12:30 AM
Moon Phase: First Quarter
Moon Illumination: 70.0%
Best Times for Fishing or Hunting
Major Periods
7:41 AM - 10:11 AM8:08 PM - 10:38 PM
Minor Periods
3:35 PM - 5:05 PM12:00 AM - 12:00 AM
Action Rating: 3 out of 5
Flood Warning issued August 3 at 10:38AM CDT until August 8 at 1:00AM CDT by NWS St Louis MO
Effective: Sun August 3, 2025, 10:38 AM
Expires: Mon August 4, 2025, 10:45 PM
...The Flood Warning is extended for the following rivers in Illinois...Missouri... Mississippi River at Clarksville. Mississippi River at Louisiana. River forecasts are based on observed precipitation and forecast precipitation for the next 24 hours. * WHAT...Minor flooding is occurring and minor flooding is forecast. * WHERE...Mississippi River at Clarksville. * WHEN...Until late Thursday night. * IMPACTS...At 25.3 feet, The road to Port Marmac, a riverside community of about 15 homes just south of Clarksville, begins flooding. * ADDITIONAL DETAILS... - At 10:30 AM CDT Sunday the stage was 25.2 feet. - Recent Activity...The maximum river stage in the 24 hours ending at 10:30 AM CDT Sunday was 25.2 feet. - Forecast...The river is expected to rise to a crest of 25.2 feet this afternoon. It will then fall below flood stage Wednesday evening. - Flood stage is 25.0 feet.
Motorists should not attempt to drive around barricades or drive cars through flooded areas. This product, along with additional weather and stream information, is available at https://water.noaa.gov/wfo/lsx
Flood Warning issued August 3 at 10:38AM CDT until August 8 at 1:00AM CDT by NWS St Louis MO
Effective: Sun August 3, 2025, 10:38 AM
Expires: Mon August 4, 2025, 10:45 PM
...The Flood Warning is extended for the following rivers in Illinois...Missouri... Mississippi River at Clarksville. Mississippi River at Louisiana. River forecasts are based on observed precipitation and forecast precipitation for the next 24 hours. * WHAT...Minor flooding is occurring and minor flooding is forecast. * WHERE...Mississippi River at Clarksville. * WHEN...Until late Thursday night. * IMPACTS...At 25.3 feet, The road to Port Marmac, a riverside community of about 15 homes just south of Clarksville, begins flooding. * ADDITIONAL DETAILS... - At 10:30 AM CDT Sunday the stage was 25.2 feet. - Recent Activity...The maximum river stage in the 24 hours ending at 10:30 AM CDT Sunday was 25.2 feet. - Forecast...The river is expected to rise to a crest of 25.2 feet this afternoon. It will then fall below flood stage Wednesday evening. - Flood stage is 25.0 feet.
Motorists should not attempt to drive around barricades or drive cars through flooded areas. This product, along with additional weather and stream information, is available at https://water.noaa.gov/wfo/lsx
Weather Forecast
Average Temperature: 70°F
Average Humidity: 74%
Wind: 8.5 mph
UV Index: 2.3
Air Quality
Nitrogen Dioxide: 14.63 μg/m3
Sulphur Dioxide: 3.68 μg/m3
Ozone: 95.56 μg/m3
Astronomical
Sun Transit: 1:06 PM
Sunset: 8:09 PM
Daylight: 14 hrs 6 mins
Moon Transit: 8:38 PM
Moonset: 12:30 AM
Moon Phase: First Quarter
Moon Illumination: 70.0%
Best Times for Fishing or Hunting
Major Periods
7:41 AM - 10:11 AM8:08 PM - 10:38 PM
Minor Periods
3:35 PM - 5:05 PM12:00 AM - 12:00 AM
Action Rating: 3 out of 5
Weather Forecast
Average Temperature: 70.4°F
Average Humidity: 86%
Wind: 7.2 mph
UV Index: 2
Air Quality
Nitrogen Dioxide: 24.24 μg/m3
Sulphur Dioxide: 6.89 μg/m3
Ozone: 86.56 μg/m3
Astronomical
Sun Transit: 1:06 PM
Sunset: 8:08 PM
Daylight: 14 hrs 4 mins
Moon Transit: 9:30 PM
Moonset: 1:08 AM
Moon Phase: Waxing Gibbous
Moon Illumination: 79.8%
Best Times for Fishing or Hunting
Major Periods
8:33 AM - 11:03 AM9:00 PM - 11:30 PM
Minor Periods
4:35 PM - 6:05 PM12:38 AM - 2:08 AM
Action Rating: 2 out of 5
Weather Forecast
Average Temperature: 74.8°F
Average Humidity: 87%
Wind: 6.5 mph
UV Index: 0
Air Quality
Nitrogen Dioxide: 15.06 μg/m3
Sulphur Dioxide: 5.96 μg/m3
Ozone: 100.44 μg/m3
Astronomical
Sun Transit: 1:06 PM
Sunset: 8:07 PM
Daylight: 14 hrs 1 mins
Moon Transit: 10:25 PM
Moonset: 1:56 AM
Moon Phase: Waxing Gibbous
Moon Illumination: 88.0%
Best Times for Fishing or Hunting
Major Periods
9:26 AM - 11:56 AM12:00 AM - 12:00 AM
Minor Periods
5:30 PM - 7:00 PM1:26 AM - 2:56 AM
Action Rating: 2 out of 5
Weather Forecast
Average Temperature: 76.5°F
Average Humidity: 82%
Wind: 9.2 mph
UV Index: 5
Air Quality
Nitrogen Dioxide: 22.16 μg/m3
Sulphur Dioxide: 5.49 μg/m3
Ozone: 107.36 μg/m3
Astronomical
Sun Transit: 1:06 PM
Sunset: 8:06 PM
Daylight: 13 hrs 59 mins
Moon Transit: 11:20 PM
Moonset: 2:52 AM
Moon Phase: Waxing Gibbous
Moon Illumination: 94.4%
Best Times for Fishing or Hunting
Major Periods
10:21 AM - 12:51 AM12:00 AM - 12:00 AM
Minor Periods
6:18 PM - 7:48 PM2:22 AM - 3:52 AM
Action Rating: 3 out of 5
Weather Forecast
Average Temperature: 77.5°F
Average Humidity: 77%
Wind: 10.3 mph
UV Index: 7
Air Quality
Nitrogen Dioxide: 33.31 μg/m3
Sulphur Dioxide: 9.31 μg/m3
Ozone: 85.62 μg/m3
Astronomical
Sun Transit: 1:06 PM
Sunset: 8:05 PM
Daylight: 13 hrs 57 mins
Moon Transit: 12:00 AM
Moonset: 3:56 AM
Moon Phase: Waxing Gibbous
Moon Illumination: 98.4%
Best Times for Fishing or Hunting
Major Periods
12:00 AM - 12:00 AM11:16 AM - 1:46 PM
Minor Periods
6:59 PM - 8:29 PM3:26 AM - 4:56 AM
Action Rating: 3 out of 5