As of 21:24 CDT

Weather in Alton, IL

50°Current weather

Alton, Friday, 16 October, 21:24

Mostly clear. Feels like 49°. High 59°, low 50°.

Pressure30.39 inHg
Wind4 mph N
Humidity93%
Visibility6.2 mi
Dew point47°

Monthly outlook for Alton, IL: average high 67.9°, average low 51°. That is 2.5° above the climate normal for October. Precipitation is expected on 3 days (about 0.8 inches), against a normal of 5 days and 1.8 inches. The warmest day looks like 24 October (79°), the coolest 17 October (41.3°).

67.9°/51°
Average high / low
+2.5°
Above normal
3 / 5
Wet days / normal
0.8 in
Precipitation this month

Ten-day blocks vs climate normal

PeriodForecast highNormalDifference
16 October – 25 October68.1°64.5°+2°
26 October – 4 November67.5°60.6°+3.8°
5 November – 14 Novemberat normal55.6°—

October records over 66 years

91.4°1 October 2019All-time high
28.6°24 October 1981All-time low

Climate normals and records are computed from the nearest reference point — Edwardsville (12 mi).

Sat, 1758° / 41°0Clear
58 °Clear

Alton, Saturday, 17 October

Clear. High 58°, low 41°.

Pressure30.56 inHg
Wind1.2 mph NE
Humidity48%
Visibility6.2 mi
Dew point35°
Sun, 1862° / 44°0Clear
62 °Clear

Alton, Sunday, 18 October

Clear. High 62°, low 44°.

Pressure30.47 inHg
Wind7.4 mph S
Humidity48%
Visibility6.2 mi
Dew point39°
Mon, 1966° / 46°0Partly cloudy
66 °Partly cloudy

Alton, Monday, 19 October

Partly cloudy. High 66°, low 46°.

Pressure30.39 inHg
Wind3.5 mph S
Humidity52%
Visibility6.2 mi
Dew point45°
Tue, 2068° / 47°0Clear
68 °Clear

Alton, Tuesday, 20 October

Clear. High 68°, low 47°.

Pressure30.36 inHg
Wind3.1 mph SE
Humidity52%
Visibility6.2 mi
Dew point46°
Wed, 2170° / 49°0Clear
70 °Clear

Alton, Wednesday, 21 October

Clear. High 70°, low 49°.

Pressure30.27 inHg
Wind3.7 mph E
Humidity47%
Visibility—
Dew point45°
Thu, 2275° / 53°0Mostly clear
75 °Mostly clear

Alton, Thursday, 22 October

Mostly clear. High 75°, low 53°.

Pressure30.18 inHg
Wind5.3 mph SE
Humidity43%
Visibility—
Dew point45°
Fri, 2378° / 56°0Partly cloudy
78 °Partly cloudy

Alton, Friday, 23 October

Partly cloudy. High 78°, low 56°.

Pressure30.21 inHg
Wind8.2 mph SE
Humidity25%
Visibility—
Dew point35°
Sat, 2479° / 57°0Overcast
79 °Overcast

Alton, Saturday, 24 October

Overcast. High 79°, low 57°.

Pressure30.21 inHg
Wind7.9 mph S
Humidity25%
Visibility—
Dew point36°
Sun, 2567° / 56°0Overcast
67 °Overcast

Alton, Sunday, 25 October

Overcast. High 67°, low 56°.

Pressure30.30 inHg
Wind10.8 mph N
Humidity44%
Visibility—
Dew point41°
Mon, 2673° / 54°0Overcast
73 °Overcast

Alton, Monday, 26 October

Overcast. High 73°, low 54°.

Pressure30.27 inHg
Wind8.5 mph NE
Humidity41%
Visibility—
Dew point42°
Tue, 2779° / 59°0.04Light rain
79 °Light rain

Alton, Tuesday, 27 October

Light rain. High 79°, low 59°.

Pressure30.15 inHg
Wind8.6 mph SW
Humidity32%
Visibility—
Dew point43°
Wed, 2865° / 55°0.15Light rain
65 °Light rain

Alton, Wednesday, 28 October

Light rain. High 65°, low 55°.

Pressure30.12 inHg
Wind10.6 mph N
Humidity75%
Visibility—
Dew point54°
Thu, 2961° / 49°0.58Rain
61 °Rain

Alton, Thursday, 29 October

Rain. High 61°, low 49°.

Pressure29.88 inHg
Wind17.4 mph SE
Humidity93%
Visibility—
Dew point50°
Fri, 3069° / 51°0Light rain
69 °Light rain

Alton, Friday, 30 October

Light rain. High 69°, low 51°.

Pressure29.65 inHg
Wind18.9 mph W
Humidity51%
Visibility—
Dew point49°
Sat, 3159° / 48°0Clear
59 °Clear

Alton, Saturday, 31 October

Clear. High 59°, low 48°.

Pressure30.15 inHg
Wind16.1 mph NW
Humidity41%
Visibility—
Dew point33°
From day 17 onward the outlook is built from 60-year climate statistics
Sun, 0161° / 46°0.18Climate normal
61 °Climate normal

Alton, Sunday, 1 November

Climate normal for this date — 60-year average.

Average high61°
Average low46°
Average precipitation0.18 in
Chance of precipitation30%
Record high79° (2016)
Record low27° (1993)
Mon, 0260° / 45°0.08Climate normal
60 °Climate normal

Alton, Monday, 2 November

Climate normal for this date — 60-year average.

Average high60°
Average low45°
Average precipitation0.08 in
Chance of precipitation30%
Record high79° (2016)
Record low27° (1966)
Tue, 0358° / 44°0.11Climate normal
58 °Climate normal

Alton, Tuesday, 3 November

Climate normal for this date — 60-year average.

Average high58°
Average low44°
Average precipitation0.11 in
Chance of precipitation30%
Record high78° (1987)
Record low20° (1991)
Wed, 0457° / 45°0.16Climate normal
57 °Climate normal

Alton, Wednesday, 4 November

Climate normal for this date — 60-year average.

Average high57°
Average low45°
Average precipitation0.16 in
Chance of precipitation28%
Record high76° (2022)
Record low20° (1991)
Thu, 0558° / 43°0.16Climate normal
58 °Climate normal

Alton, Thursday, 5 November

Climate normal for this date — 60-year average.

Average high58°
Average low43°
Average precipitation0.16 in
Chance of precipitation30%
Record high76° (1978)
Record low24° (1991)
Fri, 0657° / 42°0.09Climate normal
57 °Climate normal

Alton, Friday, 6 November

Climate normal for this date — 60-year average.

Average high57°
Average low42°
Average precipitation0.09 in
Chance of precipitation33%
Record high77° (2023)
Record low28° (1982)
Sat, 0757° / 42°0.08Climate normal
57 °Climate normal

Alton, Saturday, 7 November

Climate normal for this date — 60-year average.

Average high57°
Average low42°
Average precipitation0.08 in
Chance of precipitation22%
Record high74° (1980)
Record low17° (1991)
Sun, 0857° / 42°0.04Climate normal
57 °Climate normal

Alton, Sunday, 8 November

Climate normal for this date — 60-year average.

Average high57°
Average low42°
Average precipitation0.04 in
Chance of precipitation17%
Record high80° (2023)
Record low4° (1991)
Mon, 0958° / 43°0.1Climate normal
58 °Climate normal

Alton, Monday, 9 November

Climate normal for this date — 60-year average.

Average high58°
Average low43°
Average precipitation0.1 in
Chance of precipitation30%
Record high76° (2022)
Record low8° (1991)
Tue, 1056° / 41°0.13Climate normal
56 °Climate normal

Alton, Tuesday, 10 November

Climate normal for this date — 60-year average.

Average high56°
Average low41°
Average precipitation0.13 in
Chance of precipitation30%
Record high74° (2020)
Record low20° (2018)
Wed, 1154° / 39°0.11Climate normal
54 °Climate normal

Alton, Wednesday, 11 November

Climate normal for this date — 60-year average.

Average high54°
Average low39°
Average precipitation0.11 in
Chance of precipitation27%
Record high74° (1989)
Record low23° (2019)
Thu, 1252° / 37°0.09Climate normal
52 °Climate normal

Alton, Thursday, 12 November

Climate normal for this date — 60-year average.

Average high52°
Average low37°
Average precipitation0.09 in
Chance of precipitation25%
Record high72° (2010)
Record low12° (2019)
Fri, 1353° / 38°0.06Climate normal
53 °Climate normal

Alton, Friday, 13 November

Climate normal for this date — 60-year average.

Average high53°
Average low38°
Average precipitation0.06 in
Chance of precipitation22%
Record high77° (1999)
Record low11° (1986)
Sat, 1454° / 39°0.1Climate normal
54 °Climate normal

Alton, Saturday, 14 November

Climate normal for this date — 60-year average.

Average high54°
Average low39°
Average precipitation0.1 in
Chance of precipitation28%
Record high77° (1971)
Record low16° (1986)

About the monthly outlook

How accurate is a 30-day forecast?

The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Alton, IL are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.

What does "above normal" mean?

We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.

Where do the 66-year records come from?

They are real temperature extremes recorded in Alton, IL since 1960: the highest and lowest reading for each calendar date, with the year it happened.

How often is it updated?

The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.