Climate Alton - Illinois
| JanJa | FebFe | MarMa | AprAp | MayMa | JunJu | |
|---|---|---|---|---|---|---|
| Average high in ºF Av. high Hi | 40 | 44 | 55 | 67 | 76 | 85 |
| Average low in ºF Av. low Lo | 23 | 26 | 36 | 47 | 57 | 66 |
| Av. precipitation in inch Av. precip. Pre. | 2.42 | 2.58 | 3.18 | 4.25 | 5.12 | 3.48 |
| JulJu | AugAu | SepSe | OctOc | NovNo | DecDe | |
|---|---|---|---|---|---|---|
| Average high in ºF Av. high Hi | 89 | 88 | 81 | 69 | 56 | 43 |
| Average low in ºF Av. low Lo | 70 | 69 | 60 | 49 | 38 | 27 |
| Av. precipitation in inch Av. precip. Pre. | 3.64 | 3.15 | 3.30 | 3.29 | 3.91 | 2.98 |
What is the average weather in Alton, Illinois?
Alton experiences a humid continental climate, marked by very large seasonal temperature contrasts. Summers are hot, while winters are cold. The area is fairly wet overall, with precipitation spread relatively evenly throughout the year, though spring tends to be the wettest season.
Alton Climate Graph - Illinois Climate Chart
Daily normals Alton - Illinois - January
Day | High ºF | Low ºF | Prec/mo inch | Prec/yr inch | Snow/mo inch | Snow/yr inch |
|---|---|---|---|---|---|---|
| 1 Jan | 39.6 | 23.3 | 0.09 | 0.09 | 0.00 | 0.00 |
| 2 Jan | 39.4 | 23.1 | 0.18 | 0.18 | 0.00 | 0.00 |
| 3 Jan | 39.3 | 23.0 | 0.27 | 0.27 | 0.00 | 0.00 |
| 4 Jan | 39.2 | 22.8 | 0.37 | 0.37 | 0.00 | 0.00 |
| 5 Jan | 39.0 | 22.6 | 0.46 | 0.46 | 0.00 | 0.00 |
| 6 Jan | 38.9 | 22.4 | 0.55 | 0.55 | 0.00 | 0.00 |
| 7 Jan | 38.8 | 22.3 | 0.65 | 0.65 | 0.00 | 0.00 |
| 8 Jan | 38.7 | 22.1 | 0.74 | 0.74 | 0.00 | 0.00 |
| 9 Jan | 38.7 | 22.0 | 0.83 | 0.83 | 0.00 | 0.00 |
| 10 Jan | 38.6 | 21.8 | 0.92 | 0.92 | 0.00 | 0.00 |
| 11 Jan | 38.6 | 21.7 | 1.02 | 1.02 | 0.00 | 0.00 |
| 12 Jan | 38.5 | 21.6 | 1.11 | 1.11 | 0.00 | 0.00 |
| 13 Jan | 38.5 | 21.5 | 1.20 | 1.20 | 0.00 | 0.00 |
| 14 Jan | 38.5 | 21.4 | 1.29 | 1.29 | 0.00 | 0.00 |
| 15 Jan | 38.5 | 21.3 | 1.38 | 1.38 | 0.00 | 0.00 |
| 16 Jan | 38.5 | 21.2 | 1.47 | 1.47 | 0.00 | 0.00 |
| 17 Jan | 38.5 | 21.2 | 1.56 | 1.56 | 0.00 | 0.00 |
| 18 Jan | 38.6 | 21.1 | 1.64 | 1.64 | 0.00 | 0.00 |
| 19 Jan | 38.6 | 21.1 | 1.72 | 1.72 | 0.00 | 0.00 |
| 20 Jan | 38.7 | 21.1 | 1.80 | 1.80 | 0.00 | 0.00 |
| 21 Jan | 38.8 | 21.1 | 1.86 | 1.86 | 0.00 | 0.00 |
| 22 Jan | 38.9 | 21.1 | 1.94 | 1.94 | 0.00 | 0.00 |
| 23 Jan | 39.0 | 21.1 | 2.00 | 2.00 | 0.00 | 0.00 |
| 24 Jan | 39.1 | 21.1 | 2.07 | 2.07 | 0.00 | 0.00 |
| 25 Jan | 39.2 | 21.1 | 2.14 | 2.14 | 0.00 | 0.00 |
| 26 Jan | 39.3 | 21.2 | 2.21 | 2.21 | 0.00 | 0.00 |
| 27 Jan | 39.5 | 21.3 | 2.28 | 2.28 | 0.00 | 0.00 |
| 28 Jan | 39.6 | 21.4 | 2.35 | 2.35 | 0.00 | 0.00 |
| 29 Jan | 39.8 | 21.5 | 2.41 | 2.41 | 0.00 | 0.00 |
| 30 Jan | 40.0 | 21.6 | 2.47 | 2.47 | 0.00 | 0.00 |
| 31 Jan | 40.2 | 21.7 | 2.53 | 2.53 | 0.00 | 0.00 |
Weather history Alton - August 2026
| Day | High ºF | Low ºF | Precip. inch | Snow inch | Snow d. inch |
|---|---|---|---|---|---|
| 01 Aug | 73.9 | 66.9 | 1.20 | 0.00 | 0.0 |
| 02 Aug | - | 66.9 | 0.13 | 0.00 | 0.0 |
| 03 Aug | 84.0 | 64.0 | 0.00 | 0.00 | 0.0 |
| 04 Aug | 84.9 | 64.9 | 0.00 | 0.00 | 0.0 |
| 05 Aug | 88.0 | 66.9 | 0.00 | 0.00 | 0.0 |
| 06 Aug | 81.0 | 70.0 | 0.00 | - | - |
| 07 Aug | 89.1 | 72.0 | 0.42 | - | - |
| 08 Aug | - | - | - | - | - |
| 09 Aug | 95.0 | 73.9 | 0.00 | - | - |
| 10 Aug | 91.9 | 72.0 | 0.00 | - | - |
| 11 Aug | 95.0 | 77.0 | 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 Alton
| Aug 26 | Normal | ||
|---|---|---|---|
| Average high temperature Av. high temp. | 87.0 ºF | 40 ºF | |
| Average low temperature Av. low temp. | 69.5 ºF | 23 ºF | |
| Total precipitation Total precip. | 1.75 inch | 2.42 inch | |
| Total snowfall Total snowfall | 0.00 inch | 0 inch | |
| Highest max temperature Highest max temp. | 95.0 ºF | - | |
| Lowest max temperature Lowest max temp. | 73.9 ºF | - | |
| Highest min temperature Highest min temp. | 77.0 ºF | - | |
| Lowest min temperature Lowest min temp. | 64.0 ºF | - | |
Past weather August 2026 incomplete - Missing data
Geo Alton - Illinois
| Country | United States | |
|---|---|---|
| State | Illinois | |
| County | Madison | |
| City | Alton | |
| Zip Code | 62002 | |
| Longitude | -90.18 dec. degr. | |
| Latitude | 38.89 dec. degr. | |
| Altitude - Elevation | 495ft | |
| ICAO | - | |
| IATA | - |
Date and Time Alton - Illinois
| Local Time | 04:34 PM | |
|---|---|---|
| Sunrise | 06:11 AM | |
| Sunset | 07:59 PM | |
| Day/Night | Day | |
| Timezone | Central Daylight Time | |
| Timezone DB | America - Chicago |
Map of Alton - Illinois
USGS National Map — Open interactive map
Alton weather averages
| Annual high temperature | 66ºF |
| Annual low temperature | 47ºF |
| Average annual precip. | 41.3 inch |
Station Data
Monthly averages Alton
Longitude: -90.1843, Latitude: 38.8906
Average weather Alton, IL - 62002
Monthly: 1991-2020 normals
History: 2007-2026
Abbreviations
Average precipitation in : Av. precipitation in
Jan: January, Feb: February, ...Jan: January, Feb: February, ...Ja: January, Fe: February, ...