Monthly outlook for Mount Prospect, IL: average high 62.9°, average low 52°. That is 2.5° above the climate normal for October. Precipitation is expected on 4 days (about 1.5 inches), against a normal of 5 days and 1.7 inches. The warmest day looks like 13 October (81.3°), the coolest 17 October (38.6°).
62.9°/52°
Average high / low
+2.5°
Above normal
4 / 5
Wet days / normal
1.5 in
Precipitation this month
Ten-day blocks vs climate normal
Period
Forecast high
Normal
Difference
13 October – 22 October
65.3°
59.7°
+3.1°
23 October – 1 November
59°
56°
+1.7°
2 November – 11 November
at normal
51.4°
—
October records over 66 years
88.2°3 October 2025All-time high
26.2°31 October 2023All-time low
Climate normals and records are computed from the nearest reference point — Park Ridge (6 mi).
Wed, 1474° / 58°0.34
74 °
Mount Prospect, Wednesday, 14 October
Heavy rain. High 74°, low 58°.
Pressure30.09 inHg
Wind7.8 mph NE
Humidity67%
Visibility6.2 mi
Dew point57°
Thu, 1559° / 56°0.91
59 °
Mount Prospect, Thursday, 15 October
Rain. High 59°, low 56°.
Pressure30.03 inHg
Wind8.4 mph E
Humidity97%
Visibility2.1 mi
Dew point57°
Fri, 1656° / 46°0.01
56 °
Mount Prospect, Friday, 16 October
Light rain. High 56°, low 46°.
Pressure30.12 inHg
Wind19.3 mph NW
Humidity61%
Visibility6.2 mi
Dew point39°
Sat, 1756° / 39°0
56 °
Mount Prospect, Saturday, 17 October
Clear. High 56°, low 39°.
Pressure30.47 inHg
Wind10.2 mph SW
Humidity47%
Visibility—
Dew point33°
Sun, 1861° / 45°0
61 °
Mount Prospect, Sunday, 18 October
Mostly clear. High 61°, low 45°.
Pressure30.24 inHg
Wind13.1 mph SW
Humidity56%
Visibility—
Dew point42°
Mon, 1956° / 52°0.07
56 °
Mount Prospect, Monday, 19 October
Light rain. High 56°, low 52°.
Pressure30.24 inHg
Wind7.2 mph SW
Humidity47%
Visibility—
Dew point36°
Tue, 2063° / 53°0
63 °
Mount Prospect, Tuesday, 20 October
Overcast. High 63°, low 53°.
Pressure30.27 inHg
Wind5.6 mph SE
Humidity87%
Visibility—
Dew point56°
Wed, 2174° / 60°0
74 °
Mount Prospect, Wednesday, 21 October
Partly cloudy. High 74°, low 60°.
Pressure30.21 inHg
Wind8.3 mph S
Humidity60%
Visibility—
Dew point56°
Thu, 2272° / 64°0.01
72 °
Mount Prospect, Thursday, 22 October
Light rain. High 72°, low 64°.
Pressure30.03 inHg
Wind13.4 mph S
Humidity58%
Visibility—
Dew point55°
Fri, 2370° / 58°0.17
70 °
Mount Prospect, Friday, 23 October
Rain. High 70°, low 58°.
Pressure29.91 inHg
Wind15.9 mph SW
Humidity81%
Visibility—
Dew point59°
Sat, 2457° / 50°0
57 °
Mount Prospect, Saturday, 24 October
Overcast. High 57°, low 50°.
Pressure30.21 inHg
Wind10.8 mph W
Humidity42%
Visibility—
Dew point33°
Sun, 2557° / 44°0
57 °
Mount Prospect, Sunday, 25 October
Clear. High 57°, low 44°.
Pressure30.15 inHg
Wind7.4 mph NW
Humidity40%
Visibility—
Dew point30°
Mon, 2657° / 45°0
57 °
Mount Prospect, Monday, 26 October
Clear. High 57°, low 45°.
Pressure30.30 inHg
Wind6.4 mph NW
Humidity32%
Visibility—
Dew point25°
Tue, 2758° / 45°0
58 °
Mount Prospect, Tuesday, 27 October
Overcast. High 58°, low 45°.
Pressure30.21 inHg
Wind11.1 mph W
Humidity46%
Visibility—
Dew point35°
Wed, 2855° / 49°0
55 °
Mount Prospect, Wednesday, 28 October
Clear. High 55°, low 49°.
Pressure29.97 inHg
Wind12.3 mph NW
Humidity40%
Visibility—
Dew point30°
From day 17 onward the outlook is built from 60-year climate statistics
Thu, 2955° / 43°0.06
55 °
Mount Prospect, Thursday, 29 October
Climate normal for this date — 60-year average.
Average high55°
Average low43°
Average precipitation0.06 in
Chance of precipitation22%
Record high79° (2024)
Record low30° (1988)
Fri, 3057° / 44°0.11
57 °
Mount Prospect, Friday, 30 October
Climate normal for this date — 60-year average.
Average high57°
Average low44°
Average precipitation0.11 in
Chance of precipitation30%
Record high77° (2024)
Record low29° (2020)
Sat, 3156° / 44°0.14
56 °
Mount Prospect, Saturday, 31 October
Climate normal for this date — 60-year average.
Average high56°
Average low44°
Average precipitation0.14 in
Chance of precipitation40%
Record high72° (1974)
Record low26° (2023)
Sun, 0155° / 43°0.16
55 °
Mount Prospect, Sunday, 1 November
Climate normal for this date — 60-year average.
Average high55°
Average low43°
Average precipitation0.16 in
Chance of precipitation43%
Record high72° (2016)
Record low18° (2019)
Mon, 0254° / 42°0.12
54 °
Mount Prospect, Monday, 2 November
Climate normal for this date — 60-year average.
Average high54°
Average low42°
Average precipitation0.12 in
Chance of precipitation38%
Record high73° (1961)
Record low24° (1991)
Tue, 0353° / 41°0.06
53 °
Mount Prospect, Tuesday, 3 November
Climate normal for this date — 60-year average.
Average high53°
Average low41°
Average precipitation0.06 in
Chance of precipitation22%
Record high71° (1987)
Record low18° (1991)
Wed, 0452° / 42°0.09
52 °
Mount Prospect, Wednesday, 4 November
Climate normal for this date — 60-year average.
Average high52°
Average low42°
Average precipitation0.09 in
Chance of precipitation27%
Record high70° (2022)
Record low17° (1991)
Thu, 0553° / 41°0.13
53 °
Mount Prospect, Thursday, 5 November
Climate normal for this date — 60-year average.
Average high53°
Average low41°
Average precipitation0.13 in
Chance of precipitation33%
Record high73° (1978)
Record low20° (1991)
Fri, 0652° / 39°0.07
52 °
Mount Prospect, Friday, 6 November
Climate normal for this date — 60-year average.
Average high52°
Average low39°
Average precipitation0.07 in
Chance of precipitation30%
Record high71° (1975)
Record low24° (1991)
Sat, 0751° / 39°0.05
51 °
Mount Prospect, Saturday, 7 November
Climate normal for this date — 60-year average.
Average high51°
Average low39°
Average precipitation0.05 in
Chance of precipitation22%
Record high69° (2020)
Record low20° (1991)
Sun, 0851° / 39°0.05
51 °
Mount Prospect, Sunday, 8 November
Climate normal for this date — 60-year average.
Average high51°
Average low39°
Average precipitation0.05 in
Chance of precipitation18%
Record high74° (2020)
Record low17° (1991)
Mon, 0951° / 39°0.12
51 °
Mount Prospect, Monday, 9 November
Climate normal for this date — 60-year average.
Average high51°
Average low39°
Average precipitation0.12 in
Chance of precipitation38%
Record high72° (2020)
Record low21° (1991)
Tue, 1050° / 39°0.11
50 °
Mount Prospect, Tuesday, 10 November
Climate normal for this date — 60-year average.
Average high50°
Average low39°
Average precipitation0.11 in
Chance of precipitation33%
Record high73° (2020)
Record low18° (2017)
Wed, 1148° / 36°0.08
48 °
Mount Prospect, Wednesday, 11 November
Climate normal for this date — 60-year average.
Average high48°
Average low36°
Average precipitation0.08 in
Chance of precipitation32%
Record high69° (1964)
Record low15° (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 Mount Prospect, 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 Mount Prospect, 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.