Caledonia Weather in September (1981–2025)

📍 43.08°N, 79.95°W •
📊

September at a Glance in Caledonia

(1981–2025)
Avg High
🔥
23.2°C
Avg Low
❄️
12.5°C
Avg Temp
🌡️
17.9°C
Avg Rain
🌧️
73 mm
Avg Humidity
💧
71%
Avg Wind
🌬️
2.9 m/s
Avg Solar
☀️
4.1
kWh/m²/day
vs Annual
📈
+9°C
temp difference
🌤️Mild afternoons🌤️Cool mornings🌤️Fairly sunny🌧️Wet month🍃Light winds😊Comfortable humidity

Caledonia September Weather Overview

September is one of the warmer months of the year in Caledonia, with average highs near 23.2°C and lows around 12.5°C (mean 17.9°C). It is a relatively wet time of year, averaging 73 mm of rainfall and 71% relative humidity across the period.

Caledonia September Temperature History (1981–2025)

Range

September is one of the warmer months of the year in Caledonia. Across 45 years of records, the warmest September in Caledonia was 2024 — when the month averaged 20.7°C — while the coldest was 1993 at 15°C. Typical September days reach 23.2°C with nights near 12.5°C. The long-term trend is warming, about 0.8°C per decade.

1981–1985 vs 2021–2025

Avg Temp16.9°C→19.7°C+2.8°C
Max Temp22.1°C→25.2°C+3.1°C
Min Temp11.7°C→14.2°C+2.5°C

Trend (per decade)

Avg Temp+0.8°C/decade ↗
Max Temp+0.8°C/decade ↗
Min Temp+0.8°C/decade ↗

Distribution of Avg Temp

15.0°C–16.5°C7 yr (16%)
16.5°C–18.0°C16 yr (36%)
18.0°C–19.5°C14 yr (31%)
19.5°C–21.0°C8 yr (18%)

Caledonia September Rainfall History (1981–2025)

Range

September is a relatively wet time of year in Caledonia, averaging 73 mm of rainfall. The wettest September on record was 1986 with 154 mm, while the driest was 2023 at 26 mm.

Caledonia September Humidity History (1981–2025)

Range

Relative humidity in Caledonia during September averages 71%. The most humid September was 1992 at 77%, and the least humid was 1991 at 62%.

Caledonia September Solar History (1981–2025)

Range

September receives about 4.1 kWh/m²/day of solar energy in Caledonia. The sunniest September was 2005 at 4.7 kWh/m²/day, and the cloudiest were 1993 and 2006 at 3.2.

Caledonia September Wind History (1981–2025)

Range

Average wind speed in Caledonia during September is 2.9 m/s. The windiest September was 2010 at 3.5 m/s, while the calmest was 2025 at 2.2 m/s.

What September Feels Like in Caledonia

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

How September Ranks in Caledonia

🔥4th warmest month of the year
🌧️2nd wettest month of the year
☀️6th sunniest month of the year

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

Explore Caledonia Weather by Month

Caledonia September Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp16.8°C16.9°C18.0°C18.6°C19.5°C+2.7°C
Avg High22.1°C22.4°C23.4°C23.8°C25.0°C+2.9°C
Avg Low11.6°C11.4°C12.7°C13.5°C14.0°C+2.4°C
Avg Rain88 mm60 mm84 mm81 mm38 mm-50 mm

Extreme September Records in Caledonia

🔥Warmest September33.2°C1983
🧊Coldest September0.2°C1993
🌧️Wettest September154 mm1986
🏜️Driest September26 mm2023
🌬️Windiest September3.5 m/s2010

Key Insights for September

✅

September temperatures in Caledonia have risen by about 2.8°C between 1981–1985 and 2021–2025.

✅

September has ranged from a record low of 0.2°C (1993) to a record high of 33.2°C (1983).

✅

Rainfall in September is a relatively wet time of year, averaging 73 mm, with a wettest year of 154 mm.

Is September a Good Time to Visit Caledonia?

One of the best times to visit Caledonia

September is one of the best times to visit Caledonia. Expect days averaging 23.2°C and nights around 12.5°C (mean 17.9°C) — warmer than Caledonia's yearly average — with moderate rainfall (73 mm), so conditions are generally comfortable for sightseeing and outdoor plans.

See Caledonia'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 →

Caledonia Weather in September — In Depth

☀️ September climate overview

September is one of the warmer months of the year in Caledonia, with average highs near 23.2°C and lows around 12.5°C (mean 17.9°C). It is a relatively wet time of year, averaging 73 mm of rainfall and 71% relative humidity across the period.

🌧️ Rain, humidity & wind in September

September averages 73 mm of rainfall in Caledonia, a relatively wet time of year compared with the rest of the year. The wettest September on record saw 154 mm (1986), and the driest just 26 mm (2023). Humidity sits around 71% and average wind speed is 2.9 m/s, with solar radiation averaging 4.1 kWh/m²/day.

📈 How September has changed

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 2.8°C. Daytime highs moved from 22.1°C to 25.2°C and overnight lows from 11.7°C to 14.2°C over the same span.
September Weather in Caledonia, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
202526.0°C19.9°C13.8°C30.7°C8.0°C29 mm63%2.2 m/s4.5
2024 🔥26.3°C20.7°C15.2°C29.8°C10.0°C36 mm67%2.5 m/s4.3
202325.1°C19.6°C14.1°C32.5°C9.1°C26 mm69%2.5 m/s4.4
202224.1°C18.9°C13.6°C30.8°C5.6°C33 mm67%2.8 m/s3.9
202124.7°C19.4°C14.1°C28.9°C8.3°C77 mm67%3.3 m/s4.3
202023.7°C18.3°C12.9°C29.4°C5.2°C30 mm67%3.3 m/s4.2
201924.0°C18.9°C13.9°C28.9°C10.6°C101 mm76%2.9 m/s3.8
201824.6°C19.9°C15.2°C32.5°C8.0°C89 mm75%2.9 m/s3.9
201724.8°C19.3°C13.8°C32.0°C6.4°C70 mm71%2.3 m/s4.6
201625.7°C20.5°C15.2°C32.2°C9.6°C58 mm68%2.9 m/s4.4
201525.5°C20.3°C15.1°C31.8°C8.7°C80 mm72%2.7 m/s4.2
201422.8°C17.5°C12.3°C29.5°C6.8°C84 mm73%2.7 m/s4.1
201322.1°C16.8°C11.4°C30.5°C5.0°C80 mm73%2.7 m/s4.1
201222.5°C17.2°C12.0°C31.5°C5.6°C86 mm70%2.7 m/s4.2
201123.2°C18.4°C13.6°C32.3°C6.2°C82 mm75%3 m/s3.8
201022.6°C17.4°C12.1°C31.7°C7.0°C86 mm70%3.5 m/s3.6
200923.1°C18.0°C12.9°C27.4°C4.3°C45 mm71%2.7 m/s4.4
200823.6°C18.2°C12.7°C31.5°C7.5°C79 mm74%2.6 m/s4
200725.3°C19.4°C13.5°C33.1°C6.5°C45 mm65%2.7 m/s4.5
200620.9°C16.3°C11.7°C26.9°C4.5°C103 mm77%3.2 m/s3.2
200525.2°C19.6°C13.9°C30.7°C7.1°C90 mm70%3 m/s4.7
200424.4°C19.1°C13.8°C29.3°C8.6°C66 mm72%2.7 m/s4.6
200322.1°C17.0°C11.8°C27.8°C5.0°C122 mm74%3.1 m/s4.1
200225.4°C19.6°C13.8°C33.1°C8.4°C101 mm68%2.7 m/s4.6
200122.1°C16.7°C11.3°C30.3°C5.0°C78 mm69%2.9 m/s4.3
200021.7°C16.6°C11.4°C31.3°C2.7°C107 mm73%3.2 m/s4
199924.1°C18.3°C12.5°C31.7°C3.1°C105 mm66%2.8 m/s4.2
199825.3°C19.4°C13.5°C31.8°C6.7°C33 mm65%2.9 m/s4.3
199722.6°C17.2°C11.7°C28.1°C4.6°C53 mm70%3.3 m/s3.9
199622.3°C17.4°C12.5°C30.3°C4.5°C80 mm73%3 m/s3.4
199521.7°C15.9°C10.0°C29.8°C4.5°C41 mm65%3 m/s4.1
199422.9°C17.0°C11.2°C28.7°C5.2°C28 mm69%3 m/s3.9
1993 ❄️20.1°C15.0°C10.0°C29.7°C0.2°C64 mm70%3.3 m/s3.2
199220.8°C15.5°C10.3°C27.2°C2.8°C90 mm77%3.1 m/s4.1
199122.2°C16.5°C10.7°C30.4°C2.3°C33 mm62%2.9 m/s4.2
199021.8°C16.5°C11.2°C30.0°C3.2°C69 mm73%3.1 m/s3.6
198922.4°C16.9°C11.4°C29.3°C0.9°C77 mm70%2.9 m/s4
198822.1°C16.5°C11.0°C27.3°C6.8°C76 mm71%3.2 m/s4.3
198722.2°C17.1°C12.0°C27.7°C6.6°C65 mm75%2.5 m/s3.7
1986 🌧️22.0°C16.6°C11.2°C27.2°C3.4°C154 mm76%3.1 m/s3.6
198523.7°C18.3°C12.9°C31.2°C5.2°C35 mm69%3 m/s4.5
198421.2°C15.9°C10.7°C27.7°C5.0°C92 mm71%2.8 m/s4
198323.8°C18.2°C12.6°C33.2°C4.8°C57 mm66%3.2 m/s—
198221.4°C16.2°C11.0°C29.8°C4.7°C117 mm75%2.5 m/s—
198120.3°C15.9°C11.4°C27.4°C3.1°C121 mm77%3.1 m/s—

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

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Caledonia September Weather — FAQ

What is the average temperature in Caledonia in September?▼

The average high in September is around 23.2°C with lows near 12.5°C (mean 17.9°C), based on 45 years of NASA POWER data.

Does it rain a lot in Caledonia in September?▼

September averages 73 mm of rainfall in Caledonia, a relatively wet time of year. The wettest on record was 154 mm in 1986.

What was the hottest September on record in Caledonia?▼

The hottest September reached 33.2°C in 1983. The coldest dipped to 0.2°C in 1993.

Has September in Caledonia gotten warmer over time?▼

Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 2.8°C. Daytime highs moved from 22.1°C to 25.2°C and overnight lows from 11.7°C to 14.2°C over the same span.

Is September a good time to visit Caledonia?▼

September is one of the warmer months of the year in Caledonia and a relatively wet time of year, so plan for around 23.2°C daytime highs and 12.5°C at night.

Is September the coldest month in Caledonia?▼

Not quite — September is the 9th coolest month in Caledonia, averaging 17.9°C.

What should I pack for Caledonia in September?▼

For September in Caledonia, pack light layers you can adjust through the day, with typical highs of 23.2°C and lows of 12.5°C. Bring an umbrella or light rain jacket too.

Is Caledonia humid in September?▼

Relative humidity in September averages 71% — moderately humid.

How windy is Caledonia in September?▼

Average wind speed in September is 2.9 m/s. The windiest September on record averaged 3.5 m/s (2010).

Which September had the most rainfall in Caledonia?▼

The wettest September on record was 1986 with 154 mm. On average, September sees 73 mm.

Where does this September 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 Caledonia behaves each September, 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 September specifically, along with year-by-year records and how the month has changed over the decades.