Crystal Lake Weather in October (1981–2025)

📍 42.25°N, 88.32°W •
📊

October at a Glance in Crystal Lake

(1981–2025)
Avg High
🔥
16.0°C
Avg Low
❄️
5.5°C
Avg Temp
🌡️
10.8°C
Avg Rain
🌧️
77 mm
Avg Humidity
💧
76%
Avg Wind
🌬️
3.5 m/s
Avg Solar
☀️
2.9
kWh/m²/day
vs Annual
📈
+2.1°C
temp difference
❄️Cool afternoons❄️Cold mornings☁️Cloudier skies🌧️Wet month💨Breezy💦Humid air

Crystal Lake October Weather Overview

October is one of the warmer months of the year in Crystal Lake, with average highs near 16°C and lows around 5.5°C (mean 10.8°C). It is about average for rainfall, averaging 77 mm of rainfall and 76% relative humidity across the period.

Crystal Lake October Temperature History (1981–2025)

Range

October is one of the warmer months of the year in Crystal Lake. Across 45 years of records, the warmest October in Crystal Lake was 2021 — when the month averaged 14.5°C — while the coldest was 1987 at 7°C. Typical October days reach 16°C with nights near 5.5°C. The long-term trend is warming, about 0.5°C per decade.

1981–1985 vs 2021–2025

Avg Temp10.7°C→12.9°C+2.2°C
Max Temp15.9°C→18.3°C+2.4°C
Min Temp5.5°C→7.5°C+2°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°C8 yr (18%)
9.0°C–11.0°C18 yr (40%)
11.0°C–13.0°C14 yr (31%)
13.0°C–15.0°C5 yr (11%)

Crystal Lake October Rainfall History (1981–2025)

Range

October is about average for rainfall in Crystal Lake, averaging 77 mm of rainfall. The wettest October on record was 1985 with 167 mm, while the driest was 2005 at 15 mm.

Crystal Lake October Humidity History (1981–2025)

Range

Relative humidity in Crystal Lake during October averages 76%. The most humid October was 1986 at 85%, and the least humid was 2024 at 60%.

Crystal Lake October Solar History (1981–2025)

Range

October receives about 2.9 kWh/m²/day of solar energy in Crystal Lake. The sunniest October was 2024 at 3.7 kWh/m²/day, and the cloudiest were 1984 and 2009 at 2.2.

Crystal Lake October Wind History (1981–2025)

Range

Average wind speed in Crystal Lake during October is 3.5 m/s. The windiest October was 1990 at 4.1 m/s, while the calmest were 2005, 2013 and 2021, among others at 3.1 m/s.

What October Feels Like in Crystal Lake

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

How October Ranks in Crystal Lake

🔥6th warmest month of the year
🌵6th driest month of the year
☀️8th sunniest month of the year

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

Explore Crystal Lake Weather by Month

Crystal Lake October Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp9.8°C10.3°C10.8°C11.1°C12.2°C+2.4°C
Avg High15.1°C15.8°C15.8°C16.2°C17.5°C+2.4°C
Avg Low4.6°C4.8°C5.7°C6.0°C6.8°C+2.2°C
Avg Rain80 mm73 mm73 mm90 mm66 mm-14 mm

Extreme October Records in Crystal Lake

🔥Warmest October30.8°C2025
🧊Coldest October-7.6°C2019
🌧️Wettest October167 mm1985
🏜️Driest October15 mm2005
🌬️Windiest October4.1 m/s1990

Key Insights for October

✅

October temperatures in Crystal Lake have risen by about 2.2°C between 1981–1985 and 2021–2025.

✅

October has ranged from a record low of -7.6°C (2019) to a record high of 30.8°C (2025).

✅

Rainfall in October is about average for rainfall, averaging 77 mm, with a wettest year of 167 mm.

Is October a Good Time to Visit Crystal Lake?

A good time to visit Crystal Lake

October is a good time to visit Crystal Lake, with days averaging 16°C and nights around 5.5°C (mean 10.8°C, warmer than Crystal Lake's yearly average) and moderate rainfall. August and July are marginally more temperate, but October still suits most travellers.

See Crystal Lake'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 →

Crystal Lake Weather in October — In Depth

☀️ October climate overview

October is one of the warmer months of the year in Crystal Lake, with average highs near 16°C and lows around 5.5°C (mean 10.8°C). It is about average for rainfall, averaging 77 mm of rainfall and 76% relative humidity across the period.

🌧️ Rain, humidity & wind in October

October averages 77 mm of rainfall in Crystal Lake, about average for rainfall compared with the rest of the year. The wettest October on record saw 167 mm (1985), and the driest just 15 mm (2005). Humidity sits around 76% and average wind speed is 3.5 m/s, with solar radiation averaging 2.9 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 2.2°C. Daytime highs moved from 15.9°C to 18.3°C and overnight lows from 5.5°C to 7.5°C over the same span.
October Weather in Crystal Lake, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
202518.8°C13.7°C8.5°C30.8°C-1.1°C46 mm72%3.2 m/s3.2
202420.2°C13.8°C7.5°C28.1°C0.5°C22 mm60%3.6 m/s3.7
202316.8°C11.9°C7.0°C28.9°C-3.8°C92 mm76%3.5 m/s2.8
202216.4°C10.6°C4.8°C24.2°C-2.9°C40 mm72%3.4 m/s3.3
2021 🔥19.1°C14.5°C9.8°C29.7°C1.1°C126 mm80%3.1 m/s2.5
202013.8°C8.5°C3.1°C24.9°C-3.5°C68 mm76%3.5 m/s2.8
201914.0°C9.3°C4.7°C27.1°C-7.6°C149 mm83%3.6 m/s2.6
201814.2°C9.6°C4.9°C27.5°C-4.2°C127 mm83%3.4 m/s2.7
201717.5°C12.7°C7.9°C27.5°C-2.4°C154 mm77%3.7 m/s2.6
201617.9°C13.0°C8.0°C25.8°C1.5°C82 mm81%3.2 m/s2.6
201516.7°C11.8°C6.8°C24.8°C-2.3°C47 mm74%3.8 m/s3
201415.3°C10.3°C5.3°C23.4°C-0.2°C76 mm79%3.3 m/s2.8
201316.1°C10.7°C5.4°C26.4°C-3.4°C81 mm79%3.1 m/s2.7
201215.4°C10.0°C4.6°C25.0°C-1.9°C87 mm74%3.9 m/s2.9
201117.0°C11.6°C6.2°C26.3°C-0.8°C53 mm75%3.2 m/s3.4
201018.2°C12.3°C6.3°C29.2°C-3.3°C47 mm71%3.3 m/s3.5
200912.7°C8.5°C4.3°C20.7°C-4.1°C150 mm83%3.5 m/s2.2
200815.2°C10.4°C5.7°C26.0°C-3.0°C60 mm77%3.4 m/s3
200718.7°C13.7°C8.6°C29.1°C-0.5°C63 mm79%3.6 m/s2.9
200613.5°C8.4°C3.3°C24.6°C-2.9°C108 mm77%3.6 m/s2.8
200517.7°C12.6°C7.6°C29.8°C1.3°C15 mm74%3.1 m/s3.1
200417.2°C11.9°C6.6°C25.4°C-1.4°C61 mm73%3.6 m/s2.7
200317.0°C10.9°C4.9°C27.7°C-1.8°C42 mm70%3.1 m/s3.3
200213.6°C8.9°C4.2°C26.2°C-2.7°C63 mm77%3.2 m/s2.7
200114.9°C10.1°C5.2°C24.7°C-2.4°C136 mm79%3.9 m/s2.6
200018.0°C12.4°C6.8°C25.7°C-1.9°C31 mm74%3.2 m/s3
199916.5°C10.5°C4.5°C23.4°C-3.9°C24 mm71%3.5 m/s3.3
199816.9°C11.9°C6.9°C23.5°C-0.7°C116 mm79%3.3 m/s3
199717.1°C11.4°C5.6°C30.0°C-4.2°C43 mm71%3.5 m/s3.3
199616.3°C10.5°C4.7°C24.3°C-4.9°C77 mm74%3.8 m/s2.9
199516.1°C10.7°C5.3°C25.9°C-1.2°C120 mm76%3.8 m/s2.9
199416.6°C11.1°C5.7°C25.0°C-1.1°C43 mm74%3.3 m/s2.8
199313.8°C8.5°C3.1°C24.1°C-3.1°C28 mm80%3.6 m/s3
199214.6°C9.2°C3.8°C24.1°C-5.3°C26 mm78%3.2 m/s2.9
199114.8°C9.7°C4.6°C23.1°C-3.9°C165 mm77%3.9 m/s2.7
199015.6°C9.7°C3.8°C26.5°C-2.6°C87 mm74%4.1 m/s3
198916.4°C10.6°C4.8°C24.0°C-2.1°C34 mm74%3.7 m/s3.1
198812.6°C7.2°C1.9°C22.6°C-5.8°C59 mm67%3.7 m/s3
1987 ❄️12.6°C7.0°C1.5°C19.7°C-2.6°C30 mm74%3.3 m/s2.9
198614.9°C10.2°C5.5°C21.1°C0.2°C49 mm85%3.1 m/s2.4
1985 🌧️15.0°C10.2°C5.4°C21.9°C0.4°C167 mm79%3.3 m/s2.5
198417.6°C12.1°C6.7°C23.5°C-1.6°C152 mm79%3.2 m/s2.2
198316.0°C11.0°C5.9°C27.2°C-0.3°C78 mm75%3.6 m/s—
198217.2°C11.4°C5.6°C26.9°C-2.8°C92 mm71%3.4 m/s—
198113.9°C8.8°C3.7°C20.6°C-5.4°C57 mm78%3.3 m/s—

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

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Crystal Lake October Weather — FAQ

What is the average temperature in Crystal Lake in October?▼

The average high in October is around 16°C with lows near 5.5°C (mean 10.8°C), based on 45 years of NASA POWER data.

Does it rain a lot in Crystal Lake in October?▼

October averages 77 mm of rainfall in Crystal Lake, about average for rainfall. The wettest on record was 167 mm in 1985.

What was the hottest October on record in Crystal Lake?▼

The hottest October reached 30.8°C in 2025. The coldest dipped to -7.6°C in 2019.

Has October in Crystal Lake 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 2.2°C. Daytime highs moved from 15.9°C to 18.3°C and overnight lows from 5.5°C to 7.5°C over the same span.

Is October a good time to visit Crystal Lake?▼

October is one of the warmer months of the year in Crystal Lake and about average for rainfall, so plan for around 16°C daytime highs and 5.5°C at night.

Is October the coldest month in Crystal Lake?▼

Not quite — October is the 7th coolest month in Crystal Lake, averaging 10.8°C.

What should I pack for Crystal Lake in October?▼

For October in Crystal Lake, pack warm layers and a jacket for chilly mornings, with typical highs of 16°C and lows of 5.5°C. Bring an umbrella or light rain jacket too.

Is Crystal Lake humid in October?▼

Relative humidity in October averages 76% — quite humid.

How windy is Crystal Lake in October?▼

Average wind speed in October is 3.5 m/s. The windiest October on record averaged 4.1 m/s (1990).

Which October had the most rainfall in Crystal Lake?▼

The wettest October on record was 1985 with 167 mm. On average, October sees 77 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 Crystal Lake 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.