Monthly outlook for Deer Park, IL: average high 59.4°, average low 46.1°. That is 3° above the climate normal for October. Precipitation is expected on 5 days (about 2.0 inches), against a normal of 5 days and 1.6 inches. The warmest day looks like 22 October (72.2°), the coolest 30 October (33.8°).
59.4°/46.1°
Average high / low
+3°
Above normal
5 / 5
Wet days / normal
2.0 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
21 October – 30 October
62.3°
55.2°
+3.9°
31 October – 9 November
54.6°
51.2°
+1.9°
10 November – 19 November
at normal
46°
—
October records over 66 years
87.4°3 October 2025All-time high
27.5°31 October 2019All-time low
Climate normals and records are computed from the nearest reference point — Highwood (14 mi).
Thu, 2272° / 45°0
72 °
Deer Park, Thursday, 22 October
Clear. High 72°, low 45°.
Pressure30.27 inHg
Wind1 mph NE
Humidity63%
Visibility6.2 mi
Dew point55°
Fri, 2368° / 47°0
68 °
Deer Park, Friday, 23 October
Clear. High 68°, low 47°.
Pressure30.33 inHg
Wind3 mph SE
Humidity76%
Visibility6.2 mi
Dew point56°
Sat, 2466° / 50°0
66 °
Deer Park, Saturday, 24 October
Overcast. High 66°, low 50°.
Pressure30.39 inHg
Wind7.9 mph S
Humidity62%
Visibility6.2 mi
Dew point50°
Sun, 2567° / 53°0
67 °
Deer Park, Sunday, 25 October
Overcast. High 67°, low 53°.
Pressure30.36 inHg
Wind5.3 mph S
Humidity61%
Visibility6.2 mi
Dew point51°
Mon, 2667° / 50°0
67 °
Deer Park, Monday, 26 October
Overcast. High 67°, low 50°.
Pressure30.27 inHg
Wind7 mph S
Humidity58%
Visibility—
Dew point49°
Tue, 2757° / 50°0.09
57 °
Deer Park, Tuesday, 27 October
Light rain. High 57°, low 50°.
Pressure30.21 inHg
Wind10.2 mph SE
Humidity75%
Visibility—
Dew point46°
Wed, 2861° / 45°0.65
61 °
Deer Park, Wednesday, 28 October
Heavy rain. High 61°, low 45°.
Pressure29.94 inHg
Wind16.8 mph NW
Humidity71%
Visibility—
Dew point50°
Thu, 2947° / 38°0
47 °
Deer Park, Thursday, 29 October
Partly cloudy. High 47°, low 38°.
Pressure30.27 inHg
Wind14.1 mph NW
Humidity48%
Visibility—
Dew point26°
Fri, 3048° / 34°0.02
48 °
Deer Park, Friday, 30 October
Light rain. High 48°, low 34°.
Pressure30.18 inHg
Wind9.5 mph SW
Humidity49%
Visibility—
Dew point28°
Sat, 3160° / 45°0.05
60 °
Deer Park, Saturday, 31 October
Light rain. High 60°, low 45°.
Pressure30.03 inHg
Wind14.2 mph SW
Humidity61%
Visibility—
Dew point41°
Sun, 0161° / 50°0
61 °
Deer Park, Sunday, 1 November
Overcast. High 61°, low 50°.
Pressure30.21 inHg
Wind8.1 mph SW
Humidity55%
Visibility—
Dew point43°
Mon, 0255° / 54°0.74
55 °
Deer Park, Monday, 2 November
Rain. High 55°, low 54°.
Pressure29.88 inHg
Wind11.1 mph NE
Humidity97%
Visibility—
Dew point53°
Tue, 0354° / 47°0.47
54 °
Deer Park, Tuesday, 3 November
Light rain. High 54°, low 47°.
Pressure29.88 inHg
Wind19.5 mph NE
Humidity94%
Visibility—
Dew point52°
Wed, 0448° / 44°0.02
48 °
Deer Park, Wednesday, 4 November
Light rain. High 48°, low 44°.
Pressure30.33 inHg
Wind16.9 mph NE
Humidity51%
Visibility—
Dew point30°
Thu, 0549° / 45°0
49 °
Deer Park, Thursday, 5 November
Light rain. High 49°, low 45°.
Pressure30.09 inHg
Wind7.7 mph NE
Humidity64%
Visibility—
Dew point37°
From day 17 onward the outlook is built from 60-year climate statistics
Fri, 0651° / 40°0.09
51 °
Deer Park, Friday, 6 November
Climate normal for this date — 60-year average.
Average high51°
Average low40°
Average precipitation0.09 in
Chance of precipitation28%
Record high70° (2020)
Record low25° (1991)
Sat, 0750° / 41°0.05
50 °
Deer Park, Saturday, 7 November
Climate normal for this date — 60-year average.
Average high50°
Average low41°
Average precipitation0.05 in
Chance of precipitation18%
Record high68° (2020)
Record low21° (1991)
Sun, 0849° / 41°0.06
49 °
Deer Park, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high49°
Average low41°
Average precipitation0.06 in
Chance of precipitation17%
Record high72° (2020)
Record low18° (2019)
Mon, 0950° / 40°0.12
50 °
Deer Park, Monday, 9 November
Climate normal for this date — 60-year average.
Average high50°
Average low40°
Average precipitation0.12 in
Chance of precipitation38%
Record high72° (2020)
Record low23° (2018)
Tue, 1049° / 40°0.11
49 °
Deer Park, Tuesday, 10 November
Climate normal for this date — 60-year average.
Average high49°
Average low40°
Average precipitation0.11 in
Chance of precipitation37%
Record high72° (2022)
Record low18° (2017)
Wed, 1147° / 38°0.08
47 °
Deer Park, Wednesday, 11 November
Climate normal for this date — 60-year average.
Average high47°
Average low38°
Average precipitation0.08 in
Chance of precipitation33%
Record high64° (1964)
Record low16° (2019)
Thu, 1245° / 36°0.06
45 °
Deer Park, Thursday, 12 November
Climate normal for this date — 60-year average.
Average high45°
Average low36°
Average precipitation0.06 in
Chance of precipitation20%
Record high63° (1964)
Record low7° (2019)
Fri, 1345° / 36°0.05
45 °
Deer Park, Friday, 13 November
Climate normal for this date — 60-year average.
Average high45°
Average low36°
Average precipitation0.05 in
Chance of precipitation23%
Record high63° (1999)
Record low8° (2019)
Sat, 1446° / 37°0.07
46 °
Deer Park, Saturday, 14 November
Climate normal for this date — 60-year average.
Average high46°
Average low37°
Average precipitation0.07 in
Chance of precipitation30%
Record high64° (2025)
Record low18° (1986)
Sun, 1546° / 37°0.09
46 °
Deer Park, Sunday, 15 November
Climate normal for this date — 60-year average.
Average high46°
Average low37°
Average precipitation0.09 in
Chance of precipitation28%
Record high69° (2025)
Record low20° (2019)
Mon, 1646° / 37°0.05
46 °
Deer Park, Monday, 16 November
Climate normal for this date — 60-year average.
Average high46°
Average low37°
Average precipitation0.05 in
Chance of precipitation18%
Record high62° (2023)
Record low24° (1997)
Tue, 1746° / 37°0.09
46 °
Deer Park, Tuesday, 17 November
Climate normal for this date — 60-year average.
Average high46°
Average low37°
Average precipitation0.09 in
Chance of precipitation25%
Record high63° (2016)
Record low18° (2014)
Wed, 1846° / 37°0.11
46 °
Deer Park, Wednesday, 18 November
Climate normal for this date — 60-year average.
Average high46°
Average low37°
Average precipitation0.11 in
Chance of precipitation28%
Record high62° (2016)
Record low15° (2014)
Thu, 1946° / 37°0.07
46 °
Deer Park, Thursday, 19 November
Climate normal for this date — 60-year average.
Average high46°
Average low37°
Average precipitation0.07 in
Chance of precipitation32%
Record high63° (2020)
Record low16° (2018)
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 Deer Park, 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 Deer Park, 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.