Monthly outlook for Lemont, IL: average high 63°, average low 48.4°. That is 3.1° above the climate normal for October. Precipitation is expected on 6 days (about 2.0 inches), against a normal of 5 days and 1.7 inches. The warmest day looks like 24 October (71.5°), the coolest 2 November (39.7°).
63°/48.4°
Average high / low
+3.1°
Above normal
6 / 5
Wet days / normal
2.0 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
18 October – 27 October
63.8°
58.4°
+3°
28 October – 6 November
61.8°
54.7°
+4°
7 November – 16 November
at normal
49.1°
—
October records over 66 years
86.7°7 October 2007All-time high
23.9°26 October 1962All-time low
Climate normals and records are computed from the nearest reference point — Orland Hills (9 mi).
Mon, 1964° / 43°0
64 °
Lemont, Monday, 19 October
Clear. High 64°, low 43°.
Pressure30.42 inHg
Wind2 mph SW
Humidity63%
Visibility6.2 mi
Dew point46°
Tue, 2064° / 45°0
64 °
Lemont, Tuesday, 20 October
Clear. High 64°, low 45°.
Pressure30.39 inHg
Wind2.9 mph SE
Humidity60%
Visibility6.2 mi
Dew point48°
Wed, 2166° / 45°0
66 °
Lemont, Wednesday, 21 October
Clear. High 66°, low 45°.
Pressure30.30 inHg
Wind2.7 mph SW
Humidity61%
Visibility6.2 mi
Dew point50°
Thu, 2266° / 48°0
66 °
Lemont, Thursday, 22 October
Overcast. High 66°, low 48°.
Pressure30.30 inHg
Wind5.8 mph E
Humidity61%
Visibility—
Dew point50°
Fri, 2363° / 48°0
63 °
Lemont, Friday, 23 October
Overcast. High 63°, low 48°.
Pressure30.36 inHg
Wind7.9 mph SE
Humidity62%
Visibility—
Dew point48°
Sat, 2471° / 52°0
71 °
Lemont, Saturday, 24 October
Overcast. High 71°, low 52°.
Pressure30.27 inHg
Wind13.3 mph S
Humidity46%
Visibility—
Dew point46°
Sun, 2564° / 52°0.15
64 °
Lemont, Sunday, 25 October
Rain. High 64°, low 52°.
Pressure30.42 inHg
Wind9.6 mph NW
Humidity31%
Visibility—
Dew point28°
Mon, 2653° / 48°0.11
53 °
Lemont, Monday, 26 October
Light rain. High 53°, low 48°.
Pressure30.36 inHg
Wind5.3 mph S
Humidity71%
Visibility—
Dew point40°
Tue, 2764° / 52°0
64 °
Lemont, Tuesday, 27 October
Overcast. High 64°, low 52°.
Pressure30.30 inHg
Wind7.5 mph E
Humidity65%
Visibility—
Dew point48°
Wed, 2863° / 58°0.07
63 °
Lemont, Wednesday, 28 October
Light rain. High 63°, low 58°.
Pressure30.00 inHg
Wind9.3 mph S
Humidity68%
Visibility—
Dew point47°
Thu, 2969° / 59°0.31
69 °
Lemont, Thursday, 29 October
Light rain. High 69°, low 59°.
Pressure29.77 inHg
Wind9.9 mph S
Humidity87%
Visibility—
Dew point60°
Fri, 3069° / 55°0.5
69 °
Lemont, Friday, 30 October
Rain. High 69°, low 55°.
Pressure29.80 inHg
Wind19.3 mph S
Humidity54%
Visibility—
Dew point49°
Sat, 3166° / 48°0.85
66 °
Lemont, Saturday, 31 October
Heavy rain. High 66°, low 48°.
Pressure29.65 inHg
Wind20.5 mph SW
Humidity48%
Visibility—
Dew point37°
Sun, 0149° / 42°0
49 °
Lemont, Sunday, 1 November
Overcast. High 49°, low 42°.
Pressure30.18 inHg
Wind19.2 mph W
Humidity58%
Visibility—
Dew point32°
Mon, 0255° / 40°0
55 °
Lemont, Monday, 2 November
Overcast. High 55°, low 40°.
Pressure30.42 inHg
Wind6.3 mph S
Humidity42%
Visibility—
Dew point28°
From day 17 onward the outlook is built from 60-year climate statistics
Tue, 0353° / 40°0.07
53 °
Lemont, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high53°
Average low40°
Average precipitation0.07 in
Chance of precipitation22%
Record high73° (1987)
Record low18° (1991)
Wed, 0453° / 42°0.09
53 °
Lemont, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high53°
Average low42°
Average precipitation0.09 in
Chance of precipitation28%
Record high71° (2015)
Record low18° (1991)
Thu, 0553° / 40°0.12
53 °
Lemont, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high53°
Average low40°
Average precipitation0.12 in
Chance of precipitation30%
Record high75° (1978)
Record low19° (1991)
Fri, 0653° / 38°0.07
53 °
Lemont, Friday, 6 November
Climate normal for this date — 60-year average.
Average high53°
Average low38°
Average precipitation0.07 in
Chance of precipitation35%
Record high72° (1975)
Record low24° (1991)
Sat, 0752° / 38°0.06
52 °
Lemont, Saturday, 7 November
Climate normal for this date — 60-year average.
Average high52°
Average low38°
Average precipitation0.06 in
Chance of precipitation20%
Record high69° (2020)
Record low20° (1991)
Sun, 0852° / 38°0.06
52 °
Lemont, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high52°
Average low38°
Average precipitation0.06 in
Chance of precipitation22%
Record high74° (2020)
Record low14° (1991)
Mon, 0952° / 39°0.13
52 °
Lemont, Monday, 9 November
Climate normal for this date — 60-year average.
Average high52°
Average low39°
Average precipitation0.13 in
Chance of precipitation35%
Record high71° (1999)
Record low18° (1991)
Tue, 1051° / 38°0.14
51 °
Lemont, Tuesday, 10 November
Climate normal for this date — 60-year average.
Average high51°
Average low38°
Average precipitation0.14 in
Chance of precipitation33%
Record high72° (2020)
Record low17° (2018)
Wed, 1148° / 35°0.07
48 °
Lemont, Wednesday, 11 November
Climate normal for this date — 60-year average.
Average high48°
Average low35°
Average precipitation0.07 in
Chance of precipitation30%
Record high71° (1964)
Record low18° (2019)
Thu, 1247° / 34°0.06
47 °
Lemont, Thursday, 12 November
Climate normal for this date — 60-year average.
Average high47°
Average low34°
Average precipitation0.06 in
Chance of precipitation23%
Record high68° (1964)
Record low5° (2019)
Fri, 1347° / 34°0.06
47 °
Lemont, Friday, 13 November
Climate normal for this date — 60-year average.
Average high47°
Average low34°
Average precipitation0.06 in
Chance of precipitation20%
Record high69° (1999)
Record low3° (2019)
Sat, 1448° / 34°0.08
48 °
Lemont, Saturday, 14 November
Climate normal for this date — 60-year average.
Average high48°
Average low34°
Average precipitation0.08 in
Chance of precipitation37%
Record high70° (1971)
Record low13° (1986)
Sun, 1548° / 35°0.09
48 °
Lemont, Sunday, 15 November
Climate normal for this date — 60-year average.
Average high48°
Average low35°
Average precipitation0.09 in
Chance of precipitation33%
Record high67° (2025)
Record low20° (1982)
Mon, 1647° / 35°0.05
47 °
Lemont, Monday, 16 November
Climate normal for this date — 60-year average.
Average high47°
Average low35°
Average precipitation0.05 in
Chance of precipitation22%
Record high64° (1988)
Record low21° (1997)
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 Lemont, 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 Lemont, 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.