Currently: 36 °F. Passing clouds. (Weather station: Quebec Weather Station, Canada). See more current weatherAnnual Weather Averages in Quebec Weather Station
Quebec Weather Station is 34 miles from Alton, so the actual climate in Alton can vary a bit.
Based on weather reports collected during 1992–2021.
All Year Climate & Weather Averages in Alton
High Temp: 77 °F
Low Temp: 2 °F
Mean Temp: 41 °F
Precipitation: 3.86"
Humidity: 73%
Dew Point: 33 °F
Wind: 15 mph
Pressure: 29.98 "Hg
Visibility: 17 mi
January Climate & Weather Averages in Alton
High Temp: 20 °F
Low Temp: 2 °F
Mean Temp: 11 °F
Precipitation: 3.21"
Humidity: 75%
Dew Point: 6 °F
Wind: 18 mph
Pressure: 30.00 "Hg
Visibility: 14 mi
February Climate & Weather Averages in Alton
High Temp: 23 °F
Low Temp: 4 °F
Mean Temp: 13 °F
Precipitation: 2.68"
Humidity: 72%
Dew Point: 7 °F
Wind: 18 mph
Pressure: 30.00 "Hg
Visibility: 15 mi
March Climate & Weather Averages in Alton
High Temp: 33 °F
Low Temp: 16 °F
Mean Temp: 24 °F
Precipitation: 3.03"
Humidity: 69%
Dew Point: 16 °F
Wind: 17 mph
Pressure: 30.01 "Hg
Visibility: 17 mi
April Climate & Weather Averages in Alton
High Temp: 47 °F
Low Temp: 30 °F
Mean Temp: 39 °F
Precipitation: 3.71"
Humidity: 66%
Dew Point: 28 °F
Wind: 17 mph
Pressure: 29.96 "Hg
Visibility: 19 mi
May Climate & Weather Averages in Alton
High Temp: 63 °F
Low Temp: 42 °F
Mean Temp: 52 °F
Precipitation: 3.56"
Humidity: 64%
Dew Point: 40 °F
Wind: 16 mph
Pressure: 29.96 "Hg
Visibility: 20 mi
June Climate & Weather Averages in Alton
High Temp: 72 °F
Low Temp: 52 °F
Mean Temp: 62 °F
Precipitation: 4.63"
Humidity: 70%
Dew Point: 52 °F
Wind: 14 mph
Pressure: 29.90 "Hg
Visibility: 19 mi
July Climate & Weather Averages in Alton
High Temp: 77 °F
Low Temp: 57 °F
Mean Temp: 67 °F
Precipitation: 4.82"
Humidity: 74%
Dew Point: 58 °F
Wind: 13 mph
Pressure: 29.90 "Hg
Visibility: 19 mi
August Climate & Weather Averages in Alton
High Temp: 75 °F
Low Temp: 55 °F
Mean Temp: 65 °F
Precipitation: 4.15"
Humidity: 75%
Dew Point: 57 °F
Wind: 12 mph
Pressure: 29.96 "Hg
Visibility: 19 mi
September Climate & Weather Averages in Alton
High Temp: 66 °F
Low Temp: 47 °F
Mean Temp: 57 °F
Precipitation: 4.39"
Humidity: 78%
Dew Point: 50 °F
Wind: 13 mph
Pressure: 30.02 "Hg
Visibility: 18 mi
October Climate & Weather Averages in Alton
High Temp: 52 °F
Low Temp: 36 °F
Mean Temp: 44 °F
Precipitation: 4.49"
Humidity: 77%
Dew Point: 38 °F
Wind: 15 mph
Pressure: 30.01 "Hg
Visibility: 18 mi
November Climate & Weather Averages in Alton
High Temp: 39 °F
Low Temp: 26 °F
Mean Temp: 32 °F
Precipitation: 3.61"
Humidity: 79%
Dew Point: 26 °F
Wind: 16 mph
Pressure: 30.02 "Hg
Visibility: 15 mi
December Climate & Weather Averages in Alton
High Temp: 27 °F
Low Temp: 12 °F
Mean Temp: 20 °F
Precipitation: 4.03"
Humidity: 80%
Dew Point: 15 °F
Wind: 16 mph
Pressure: 30.01 "Hg
Visibility: 13 mi