As of 21:57 CDT

Weather in Chester, IL

70°

Chester, Wednesday, 14 October, 21:57

Partly cloudy. Feels like 71°. High 78°, low 70°.

Pressure30.03 inHg

Wind0 mph N

Humidity94%

Visibility6.2 mi

Dew point69°

See detailed hourly forecast

Monthly outlook for Chester, IL: average high 69.3°, average low 53°. That is 2° above the climate normal for October. Precipitation is expected on 6 days (about 4.0 inches), against a normal of 4 days and 1.9 inches. The warmest day looks like 23 October (79.6°), the coolest 18 October (42.8°).

69.3°/53°

Average high / low

+2°

Above normal

6 / 4

Wet days / normal

4.0 in

Precipitation this month

Ten-day blocks vs climate normal

Period	Forecast high	Normal	Difference
14 October – 23 October	71.5°	67.1°	+2.4°
24 October – 2 November	65.7°	63.1°	+1.5°
3 November – 12 November	at normal	58.3°	—

October records over 66 years

93.6°1 October 2019All-time high

26.8°24 October 1981All-time low

Climate normals and records are computed from the nearest reference point — St. Mary (7 mi).

Thu, 1579° / 65°

0.93

79 °

Chester, Thursday, 15 October

Heavy rain. High 79°, low 65°.

Pressure30.00 inHg

Wind6.6 mph S

Humidity71%

Visibility6.2 mi

Dew point72°

Fri, 1666° / 52°

0.37

66 °

Chester, Friday, 16 October

Heavy rain. High 66°, low 52°.

Pressure30.21 inHg

Wind18.6 mph NW

Humidity46%

Visibility6.2 mi

Dew point37°

Sat, 1757° / 45°

57 °

Chester, Saturday, 17 October

Clear. High 57°, low 45°.

Pressure30.56 inHg

Wind6.2 mph N

Humidity54%

Visibility6.2 mi

Dew point38°

Sun, 1862° / 43°

62 °

Chester, Sunday, 18 October

Clear. High 62°, low 43°.

Pressure30.50 inHg

Wind4.8 mph SE

Humidity49%

Visibility6.2 mi

Dew point38°

Mon, 1967° / 46°

67 °

Chester, Monday, 19 October

Overcast. High 67°, low 46°.

Pressure30.39 inHg

Wind6.7 mph S

Humidity43%

Visibility—

Dew point40°

Tue, 2071° / 47°

71 °

Chester, Tuesday, 20 October

Clear. High 71°, low 47°.

Pressure30.33 inHg

Wind7.3 mph SE

Humidity47%

Visibility—

Dew point45°

Wed, 2177° / 57°

77 °

Chester, Wednesday, 21 October

Partly cloudy. High 77°, low 57°.

Pressure30.27 inHg

Wind8.3 mph SE

Humidity41%

Visibility—

Dew point48°

Thu, 2279° / 57°

79 °

Chester, Thursday, 22 October

Mostly clear. High 79°, low 57°.

Pressure30.21 inHg

Wind11.7 mph S

Humidity37%

Visibility—

Dew point47°

Fri, 2380° / 63°

80 °

Chester, Friday, 23 October

Overcast. High 80°, low 63°.

Pressure30.09 inHg

Wind19.6 mph S

Humidity54%

Visibility—

Dew point57°

Sat, 2476° / 65°

0.57

76 °

Chester, Saturday, 24 October

Rain. High 76°, low 65°.

Pressure30.18 inHg

Wind11.6 mph S

Humidity67%

Visibility—

Dew point63°

Sun, 2566° / 57°

1.26

66 °

Chester, Sunday, 25 October

Rain. High 66°, low 57°.

Pressure30.12 inHg

Wind13.2 mph NW

Humidity94%

Visibility—

Dew point62°

Mon, 2659° / 47°

0.59

59 °

Chester, Monday, 26 October

Rain. High 59°, low 47°.

Pressure30.15 inHg

Wind16.2 mph NW

Humidity46%

Visibility—

Dew point35°

Tue, 2762° / 43°

62 °

Chester, Tuesday, 27 October

Overcast. High 62°, low 43°.

Pressure30.12 inHg

Wind8.1 mph NE

Humidity40%

Visibility—

Dew point34°

Wed, 2864° / 45°

64 °

Chester, Wednesday, 28 October

Partly cloudy. High 64°, low 45°.

Pressure29.91 inHg

Wind8.2 mph N

Humidity46%

Visibility—

Dew point39°

Thu, 2968° / 47°

68 °

Chester, Thursday, 29 October

Clear. High 68°, low 47°.

Pressure30.06 inHg

Wind11.6 mph NW

Humidity42%

Visibility—

Dew point41°

From day 17 onward the outlook is built from 60-year climate statistics

Fri, 3064° / 48°

0.13

64 °

Chester, Friday, 30 October

Climate normal for this date — 60-year average.

Average high64°

Average low48°

Average precipitation0.13 in

Chance of precipitation28%

Record high80° (1971)

Record low29° (1980)

Sat, 3164° / 48°

0.17

64 °

Chester, Saturday, 31 October

Climate normal for this date — 60-year average.

Average high64°

Average low48°

Average precipitation0.17 in

Chance of precipitation38%

Record high78° (1968)

Record low28° (2023)

Sun, 0163° / 47°

0.16

63 °

Chester, Sunday, 1 November

Climate normal for this date — 60-year average.

Average high63°

Average low47°

Average precipitation0.16 in

Chance of precipitation35%

Record high80° (2016)

Record low26° (1993)

Mon, 0261° / 46°

0.09

61 °

Chester, Monday, 2 November

Climate normal for this date — 60-year average.

Average high61°

Average low46°

Average precipitation0.09 in

Chance of precipitation30%

Record high80° (2016)

Record low29° (1966)

Tue, 0360° / 45°

0.08

60 °

Chester, Tuesday, 3 November

Climate normal for this date — 60-year average.

Average high60°

Average low45°

Average precipitation0.08 in

Chance of precipitation30%

Record high78° (1987)

Record low24° (1991)

Wed, 0460° / 45°

0.11

60 °

Chester, Wednesday, 4 November

Climate normal for this date — 60-year average.

Average high60°

Average low45°

Average precipitation0.11 in

Chance of precipitation25%

Record high77° (1978)

Record low20° (1991)

Thu, 0559° / 44°

0.15

59 °

Chester, Thursday, 5 November

Climate normal for this date — 60-year average.

Average high59°

Average low44°

Average precipitation0.15 in

Chance of precipitation35%

Record high77° (1978)

Record low24° (1991)

Fri, 0658° / 42°

0.11

58 °

Chester, Friday, 6 November

Climate normal for this date — 60-year average.

Average high58°

Average low42°

Average precipitation0.11 in

Chance of precipitation32%

Record high77° (1999)

Record low27° (1982)

Sat, 0759° / 43°

0.1

59 °

Chester, Saturday, 7 November

Climate normal for this date — 60-year average.

Average high59°

Average low43°

Average precipitation0.1 in

Chance of precipitation20%

Record high77° (1999)

Record low22° (1993)

Sun, 0859° / 43°

0.03

59 °

Chester, Sunday, 8 November

Climate normal for this date — 60-year average.

Average high59°

Average low43°

Average precipitation0.03 in

Chance of precipitation15%

Record high79° (1999)

Record low16° (1991)

Mon, 0960° / 43°

0.07

60 °

Chester, Monday, 9 November

Climate normal for this date — 60-year average.

Average high60°

Average low43°

Average precipitation0.07 in

Chance of precipitation25%

Record high77° (2022)

Record low19° (1991)

Tue, 1058° / 42°

0.13

58 °

Chester, Tuesday, 10 November

Climate normal for this date — 60-year average.

Average high58°

Average low42°

Average precipitation0.13 in

Chance of precipitation28%

Record high76° (1999)

Record low20° (2018)

Wed, 1156° / 40°

0.11

56 °

Chester, Wednesday, 11 November

Climate normal for this date — 60-year average.

Average high56°

Average low40°

Average precipitation0.11 in

Chance of precipitation28%

Record high76° (2010)

Record low24° (1960)

Thu, 1254° / 38°

0.08

54 °

Chester, Thursday, 12 November

Climate normal for this date — 60-year average.

Average high54°

Average low38°

Average precipitation0.08 in

Chance of precipitation23%

Record high74° (2010)

Record low14° (2019)

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 Chester, 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 Chester, 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.