Mount Prospect Weather in October (1981–2025)

📍 42.07°N, 87.93°W •
📊

October at a Glance in Mount Prospect

(1981–2025)
Avg High
🔥
16.7°C
Avg Low
❄️
5.6°C
Avg Temp
🌡️
11.1°C
Avg Rain
🌧️
83 mm
Avg Humidity
💧
75%
Avg Wind
🌬️
3.3 m/s
Avg Solar
☀️
2.7
kWh/m²/day
vs Annual
📈
+1.8°C
temp difference
❄️Cool afternoons❄️Cold mornings☁️Cloudier skies🌧️Wet month💨Breezy💦Humid air

Mount Prospect October Weather Overview

October is one of the warmer months of the year in Mount Prospect, with average highs near 16.7°C and lows around 5.6°C (mean 11.1°C). It is about average for rainfall, averaging 83 mm of rainfall and 75% relative humidity across the period.

Mount Prospect October Temperature History (1981–2025)

Range

October is one of the warmer months of the year in Mount Prospect. Across 45 years of records, the warmest October in Mount Prospect was 2021 — when the month averaged 14.7°C — while the coldest was 1987 at 7.2°C. Typical October days reach 16.7°C with nights near 5.6°C. The long-term trend is warming, about 0.5°C per decade.

1981–1985 vs 2021–2025

Avg Temp11.2°C→13.3°C+2.1°C
Max Temp16.8°C→19.0°C+2.2°C
Min Temp5.7°C→7.5°C+1.8°C

Trend (per decade)

Avg Temp+0.5°C/decade ↗
Max Temp+0.5°C/decade ↗
Min Temp+0.6°C/decade ↗

Distribution of Avg Temp

7.0°C–9.0°C5 yr (11%)
9.0°C–11.0°C17 yr (38%)
11.0°C–13.0°C17 yr (38%)
13.0°C–15.0°C6 yr (13%)

Mount Prospect October Rainfall History (1981–2025)

Range

October is about average for rainfall in Mount Prospect, averaging 83 mm of rainfall. The wettest October on record was 2017 with 209 mm, while the driest was 2005 at 21 mm.

Mount Prospect October Humidity History (1981–2025)

Range

Relative humidity in Mount Prospect during October averages 75%. The most humid October was 1986 at 85%, and the least humid was 2024 at 59%.

Mount Prospect October Solar History (1981–2025)

Range

October receives about 2.7 kWh/m²/day of solar energy in Mount Prospect. The sunniest October was 2024 at 3.5 kWh/m²/day, and the cloudiest were 1986 and 2009 at 2.1.

Mount Prospect October Wind History (1981–2025)

Range

Average wind speed in Mount Prospect during October is 3.3 m/s. The windiest Octobers were 1990 and 2012 at 3.8 m/s, while the calmest were 1986, 2003 and 2011 at 2.9 m/s.

What October Feels Like in Mount Prospect

🌅
Cold
Morning
🌞
Cool
Afternoon
🌆
Cold
Evening
Rain chanceModerate
Outdoor comfort★★★☆☆

How October Ranks in Mount Prospect

🔥6th warmest month of the year
🌧️6th wettest month of the year
☀️8th sunniest month of the year

Ranked against the other 11 months using 1981–2025 averages.

Explore Mount Prospect Weather by Month

Mount Prospect October Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp10.3°C10.6°C11.2°C11.5°C12.6°C+2.3°C
Avg High15.8°C16.4°C16.6°C16.9°C18.4°C+2.6°C
Avg Low4.7°C4.8°C5.8°C6.1°C6.8°C+2.1°C
Avg Rain73 mm83 mm82 mm96 mm76 mm+3 mm

Extreme October Records in Mount Prospect

🔥Warmest October31.7°C2025
🧊Coldest October-8.0°C2019
🌧️Wettest October209 mm2017
🏜️Driest October21 mm2005
🌬️Windiest October3.8 m/s1990

Key Insights for October

✅

October temperatures in Mount Prospect have risen by about 2.1°C between 1981–1985 and 2021–2025.

✅

October has ranged from a record low of -8°C (2019) to a record high of 31.7°C (2025).

✅

Rainfall in October is about average for rainfall, averaging 83 mm, with a wettest year of 209 mm.

Is October a Good Time to Visit Mount Prospect?

A good time to visit Mount Prospect

October is a good time to visit Mount Prospect, with days averaging 16.7°C and nights around 5.6°C (mean 11.1°C, warmer than Mount Prospect's yearly average) and higher rainfall. August and July are marginally more temperate, but October still suits most travellers.

See Mount Prospect's complete weather history All 12 months side by side, 1981–2025 records, annual trends and long-term averages in one place. View full history →

Mount Prospect Weather in October — In Depth

☀️ October climate overview

October is one of the warmer months of the year in Mount Prospect, with average highs near 16.7°C and lows around 5.6°C (mean 11.1°C). It is about average for rainfall, averaging 83 mm of rainfall and 75% relative humidity across the period.

🌧️ Rain, humidity & wind in October

October averages 83 mm of rainfall in Mount Prospect, about average for rainfall compared with the rest of the year. The wettest October on record saw 209 mm (2017), and the driest just 21 mm (2005). Humidity sits around 75% and average wind speed is 3.3 m/s, with solar radiation averaging 2.7 kWh/m²/day.

📈 How October has changed

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average October temperatures have risen by about 2.1°C. Daytime highs moved from 16.8°C to 19°C and overnight lows from 5.7°C to 7.5°C over the same span.
October Weather in Mount Prospect, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
202519.6°C13.9°C8.3°C31.7°C-1.3°C55 mm70%3.1 m/s3
202421.1°C14.3°C7.4°C28.9°C0.5°C28 mm59%3.4 m/s3.5
202317.5°C12.3°C7.0°C29.8°C-4.1°C86 mm75%3.4 m/s2.5
202217.4°C11.1°C4.8°C25.4°C-3.1°C52 mm69%3.3 m/s3
2021 🔥19.5°C14.7°C9.8°C30.6°C1.5°C158 mm80%3 m/s2.3
202015.1°C9.4°C3.6°C26.1°C-3.4°C77 mm75%3.4 m/s2.6
201914.7°C9.7°C4.8°C27.9°C-8.0°C149 mm82%3.4 m/s2.5
201815.3°C10.2°C5.1°C29.0°C-4.4°C123 mm81%3.2 m/s2.6
2017 🌧️18.1°C13.0°C8.0°C27.6°C-3.2°C209 mm77%3.5 m/s2.5
201618.5°C13.3°C8.1°C26.7°C1.5°C87 mm81%3.1 m/s2.5
201517.4°C12.2°C7.0°C25.2°C-2.1°C50 mm73%3.6 m/s2.8
201415.7°C10.7°C5.6°C24.0°C0.3°C80 mm79%3.1 m/s2.7
201316.8°C11.2°C5.5°C27.0°C-3.7°C95 mm77%3 m/s2.7
201215.7°C10.2°C4.6°C25.4°C-1.5°C84 mm74%3.8 m/s2.6
201117.4°C11.7°C5.9°C26.9°C-1.0°C49 mm75%2.9 m/s3.3
201019.0°C12.7°C6.4°C29.9°C-3.8°C38 mm69%3.2 m/s3.3
200913.1°C8.8°C4.5°C20.8°C-3.7°C171 mm83%3.4 m/s2.1
200815.7°C10.6°C5.5°C27.0°C-3.4°C62 mm78%3.2 m/s2.8
200719.8°C14.3°C8.7°C30.3°C-0.3°C63 mm76%3.5 m/s2.9
200614.0°C8.8°C3.5°C26.1°C-3.1°C116 mm77%3.4 m/s2.8
200518.2°C12.9°C7.6°C30.2°C0.5°C21 mm73%3 m/s2.9
200417.8°C12.2°C6.5°C25.9°C-2.2°C67 mm73%3.4 m/s2.7
200317.4°C11.2°C4.9°C28.2°C-2.1°C47 mm70%2.9 m/s3.1
200214.9°C9.7°C4.4°C27.6°C-2.2°C55 mm75%3 m/s2.6
200115.6°C10.4°C5.3°C26.2°C-2.1°C172 mm79%3.7 m/s2.5
200019.0°C12.8°C6.7°C26.7°C-2.5°C45 mm74%3 m/s2.9
199917.2°C10.8°C4.5°C24.9°C-4.0°C27 mm70%3.2 m/s3
199817.7°C12.3°C6.8°C24.6°C-0.4°C117 mm78%3 m/s2.8
199717.5°C11.6°C5.6°C30.1°C-4.5°C53 mm70%3.3 m/s2.9
199616.6°C10.6°C4.7°C24.8°C-5.0°C65 mm75%3.5 m/s2.8
199516.7°C11.0°C5.4°C26.6°C-0.6°C120 mm75%3.7 m/s2.8
199417.1°C11.3°C5.5°C25.5°C-1.4°C70 mm73%3.2 m/s2.6
199314.2°C8.8°C3.3°C24.6°C-3.0°C50 mm80%3.4 m/s2.8
199215.3°C9.5°C3.7°C24.8°C-5.5°C27 mm78%3 m/s2.6
199115.7°C10.3°C4.9°C23.8°C-3.3°C190 mm77%3.7 m/s2.5
199016.0°C9.9°C3.8°C26.9°C-2.7°C107 mm75%3.8 m/s2.9
198916.8°C10.8°C4.8°C25.0°C-1.9°C35 mm74%3.5 m/s2.8
198813.3°C7.6°C2.0°C22.8°C-5.9°C78 mm66%3.5 m/s2.5
1987 ❄️13.1°C7.2°C1.4°C20.8°C-2.7°C36 mm73%3.1 m/s2.7
198615.5°C10.6°C5.6°C21.8°C-0.4°C71 mm85%2.9 m/s2.1
198515.9°C10.8°C5.8°C23.3°C0.7°C141 mm78%3.2 m/s2.5
198418.4°C12.8°C7.1°C24.5°C-0.7°C103 mm77%3 m/s2.2
198316.6°C11.3°C6.0°C27.5°C-0.7°C84 mm75%3.4 m/s—
198218.1°C11.9°C5.7°C27.4°C-3.3°C69 mm69%3.1 m/s—
198114.8°C9.3°C3.7°C22.4°C-5.6°C43 mm77%3.1 m/s—

Actual recorded October data for each year, 1981–2025 — sourced from NASA POWER.

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Mount Prospect October Weather — FAQ

What is the average temperature in Mount Prospect in October?▼

The average high in October is around 16.7°C with lows near 5.6°C (mean 11.1°C), based on 45 years of NASA POWER data.

Does it rain a lot in Mount Prospect in October?▼

October averages 83 mm of rainfall in Mount Prospect, about average for rainfall. The wettest on record was 209 mm in 2017.

What was the hottest October on record in Mount Prospect?▼

The hottest October reached 31.7°C in 2025. The coldest dipped to -8°C in 2019.

Has October in Mount Prospect gotten warmer over time?▼

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average October temperatures have risen by about 2.1°C. Daytime highs moved from 16.8°C to 19°C and overnight lows from 5.7°C to 7.5°C over the same span.

Is October a good time to visit Mount Prospect?▼

October is one of the warmer months of the year in Mount Prospect and about average for rainfall, so plan for around 16.7°C daytime highs and 5.6°C at night.

Is October the coldest month in Mount Prospect?▼

Not quite — October is the 7th coolest month in Mount Prospect, averaging 11.1°C.

What should I pack for Mount Prospect in October?▼

For October in Mount Prospect, pack warm layers and a jacket for chilly mornings, with typical highs of 16.7°C and lows of 5.6°C. Bring an umbrella or light rain jacket too.

Is Mount Prospect humid in October?▼

Relative humidity in October averages 75% — quite humid.

How windy is Mount Prospect in October?▼

Average wind speed in October is 3.3 m/s. The windiest October on record averaged 3.8 m/s (1990).

Which October had the most rainfall in Mount Prospect?▼

The wettest October on record was 2017 with 209 mm. On average, October sees 83 mm.

Where does this October weather data come from?▼

All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.

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Explore how the weather in Mount Prospect behaves each October, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for October specifically, along with year-by-year records and how the month has changed over the decades.