Milton Weather in September (1981–2025)

📍 43.51°N, 79.88°W •
📊

September at a Glance in Milton

(1981–2025)
Avg High
🔥
23.2°C
Avg Low
❄️
11.1°C
Avg Temp
🌡️
17.2°C
Avg Rain
🌧️
70 mm
Avg Humidity
💧
71%
Avg Wind
🌬️
2.6 m/s
Avg Solar
☀️
4.1
kWh/m²/day
vs Annual
📈
+9.2°C
temp difference
🌤️Mild afternoons🌤️Cool mornings🌤️Fairly sunny🌧️Wet month🍃Light winds😊Comfortable humidity

Milton September Weather Overview

September is one of the warmer months of the year in Milton, with average highs near 23.2°C and lows around 11.1°C (mean 17.2°C). It is a relatively wet time of year, averaging 70 mm of rainfall and 71% relative humidity across the period.

Milton September Temperature History (1981–2025)

Range

September is one of the warmer months of the year in Milton. Across 45 years of records, the warmest September in Milton was 2002 — when the month averaged 20.1°C — while the coldest was 1993 at 14.2°C. Typical September days reach 23.2°C with nights near 11.1°C. The long-term trend is warming, about 0.7°C per decade.

1981–1985 vs 2021–2025

Avg Temp16.1°C→18.7°C+2.6°C
Max Temp22.0°C→24.8°C+2.8°C
Min Temp10.3°C→12.6°C+2.3°C

Trend (per decade)

Avg Temp+0.7°C/decade ↗
Max Temp+0.7°C/decade ↗
Min Temp+0.7°C/decade ↗

Distribution of Avg Temp

14.0°C–15.8°C10 yr (22%)
15.8°C–17.5°C17 yr (38%)
17.5°C–19.3°C14 yr (31%)
19.3°C–21.0°C4 yr (9%)

Milton September Rainfall History (1981–2025)

Range

September is a relatively wet time of year in Milton, averaging 70 mm of rainfall. The wettest September on record was 1986 with 176 mm, while the driest was 2023 at 20 mm.

Milton September Humidity History (1981–2025)

Range

Relative humidity in Milton during September averages 71%. The most humid September was 1986 at 78%, and the least humid was 1991 at 63%.

Milton September Solar History (1981–2025)

Range

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

Milton September Wind History (1981–2025)

Range

Average wind speed in Milton during September is 2.6 m/s. The windiest September was 2010 at 3.1 m/s, while the calmest were 2017 and 2025 at 2 m/s.

What September Feels Like in Milton

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

How September Ranks in Milton

🔥4th warmest month of the year
🌧️3rd wettest month of the year
☀️6th sunniest month of the year

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

Explore Milton Weather by Month

Milton September Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp16.2°C16.2°C17.5°C17.8°C18.5°C+2.3°C
Avg High22.2°C22.3°C23.7°C23.7°C24.6°C+2.4°C
Avg Low10.3°C10.0°C11.4°C12.0°C12.4°C+2.1°C
Avg Rain80 mm67 mm71 mm75 mm54 mm-27 mm

Extreme September Records in Milton

🔥Warmest September35.5°C2002
🧊Coldest September-1.0°C1993
🌧️Wettest September176 mm1986
🏜️Driest September20 mm2023
🌬️Windiest September3.1 m/s2010

Key Insights for September

✅

September temperatures in Milton have risen by about 2.6°C between 1981–1985 and 2021–2025.

✅

September has ranged from a record low of -1°C (1993) to a record high of 35.5°C (2002).

✅

Rainfall in September is a relatively wet time of year, averaging 70 mm, with a wettest year of 176 mm.

Is September a Good Time to Visit Milton?

One of the best times to visit Milton

September is one of the best times to visit Milton. Expect days averaging 23.2°C and nights around 11.1°C (mean 17.2°C) — warmer than Milton's yearly average — with moderate rainfall (70 mm), so conditions are generally comfortable for sightseeing and outdoor plans.

See Milton'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 →

Milton Weather in September — In Depth

☀️ September climate overview

September is one of the warmer months of the year in Milton, with average highs near 23.2°C and lows around 11.1°C (mean 17.2°C). It is a relatively wet time of year, averaging 70 mm of rainfall and 71% relative humidity across the period.

🌧️ Rain, humidity & wind in September

September averages 70 mm of rainfall in Milton, a relatively wet time of year compared with the rest of the year. The wettest September on record saw 176 mm (1986), and the driest just 20 mm (2023). Humidity sits around 71% and average wind speed is 2.6 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 2.6°C. Daytime highs moved from 22°C to 24.8°C and overnight lows from 10.3°C to 12.6°C over the same span.
September Weather in Milton, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
202525.3°C18.9°C12.6°C29.3°C6.7°C52 mm65%2 m/s4.5
202425.9°C19.8°C13.7°C30.0°C8.0°C36 mm69%2.2 m/s4.3
202324.8°C18.7°C12.6°C34.4°C6.9°C20 mm69%2.2 m/s4.4
202224.2°C18.1°C12.0°C32.9°C3.8°C32 mm67%2.4 m/s3.9
202123.7°C17.9°C12.1°C28.4°C6.1°C131 mm72%2.8 m/s4.3
202023.6°C17.4°C11.2°C29.8°C2.9°C50 mm69%2.9 m/s4.2
201924.4°C18.4°C12.4°C30.5°C8.1°C53 mm74%2.7 m/s3.8
201824.2°C19.0°C13.8°C33.3°C6.9°C64 mm75%2.6 m/s3.9
201725.2°C18.9°C12.6°C33.4°C5.1°C38 mm70%2 m/s4.6
201625.2°C19.4°C13.6°C32.4°C7.3°C62 mm69%2.5 m/s4.4
201525.6°C19.7°C13.8°C33.5°C7.5°C66 mm71%2.4 m/s4.2
201422.3°C16.5°C10.8°C29.8°C4.8°C113 mm75%2.4 m/s4.1
201322.4°C16.1°C9.9°C33.5°C3.2°C84 mm73%2.4 m/s4.1
201222.1°C16.2°C10.4°C31.2°C4.2°C94 mm70%2.4 m/s4.2
201123.0°C17.6°C12.2°C33.1°C5.0°C86 mm75%2.6 m/s3.8
201022.3°C16.5°C10.7°C33.3°C5.6°C87 mm72%3.1 m/s3.6
200923.1°C17.2°C11.4°C28.2°C3.1°C38 mm71%2.3 m/s4.4
200823.0°C17.2°C11.4°C32.3°C5.8°C92 mm75%2.2 m/s4
200725.8°C18.9°C12.0°C34.5°C3.4°C37 mm65%2.6 m/s4.5
200621.1°C15.7°C10.4°C27.8°C2.9°C84 mm75%2.9 m/s3.2
200525.8°C19.1°C12.4°C32.3°C4.7°C60 mm68%2.8 m/s4.7
200425.1°C18.7°C12.2°C30.1°C6.0°C40 mm69%2.4 m/s4.6
200322.3°C16.6°C10.8°C29.1°C3.3°C95 mm72%2.8 m/s4.1
2002 🔥26.7°C20.1°C13.5°C35.5°C7.1°C63 mm64%2.5 m/s4.6
200122.4°C16.4°C10.4°C30.8°C2.8°C84 mm69%2.7 m/s4.3
200021.3°C15.5°C9.7°C31.6°C0.4°C113 mm75%2.8 m/s4
199924.8°C18.1°C11.3°C32.7°C2.2°C74 mm64%2.6 m/s4.2
199825.5°C18.8°C12.1°C32.9°C5.2°C38 mm64%2.6 m/s4.3
199722.4°C16.3°C10.1°C28.5°C2.9°C53 mm71%2.9 m/s3.9
199622.1°C16.7°C11.3°C30.5°C3.1°C109 mm73%2.6 m/s3.4
199521.5°C15.1°C8.6°C30.5°C3.1°C32 mm65%2.6 m/s4.1
199422.7°C16.3°C9.9°C30.2°C4.5°C41 mm71%2.6 m/s3.9
1993 ❄️19.7°C14.2°C8.6°C29.6°C-1.0°C86 mm71%2.9 m/s3.2
199220.5°C14.8°C9.0°C26.8°C0.9°C118 mm78%2.9 m/s4.1
199122.1°C15.7°C9.4°C31.5°C0.5°C43 mm63%2.6 m/s4.2
199022.0°C16.0°C9.9°C29.6°C2.2°C81 mm72%2.8 m/s3.6
198922.9°C16.8°C10.6°C29.9°C-0.6°C58 mm67%2.6 m/s4
198822.8°C16.3°C9.9°C29.0°C5.8°C66 mm69%3 m/s4.3
198722.7°C16.8°C10.9°C29.3°C5.2°C45 mm73%2.4 m/s3.7
1986 🌧️21.2°C15.4°C9.6°C26.8°C2.5°C176 mm78%2.7 m/s3.6
198523.4°C17.3°C11.3°C31.0°C3.3°C37 mm71%2.6 m/s4.5
198421.0°C15.0°C9.0°C27.8°C3.3°C81 mm71%2.5 m/s4
198324.3°C17.7°C11.2°C34.5°C3.9°C53 mm64%2.9 m/s—
198221.4°C15.5°C9.7°C30.6°C3.5°C95 mm75%2.3 m/s—
198119.9°C15.0°C10.2°C27.3°C1.2°C114 mm78%2.7 m/s—

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

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Milton September Weather — FAQ

What is the average temperature in Milton in September?▼

The average high in September is around 23.2°C with lows near 11.1°C (mean 17.2°C), based on 45 years of NASA POWER data.

Does it rain a lot in Milton in September?▼

September averages 70 mm of rainfall in Milton, a relatively wet time of year. The wettest on record was 176 mm in 1986.

What was the hottest September on record in Milton?▼

The hottest September reached 35.5°C in 2002. The coldest dipped to -1°C in 1993.

Has September in Milton 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 2.6°C. Daytime highs moved from 22°C to 24.8°C and overnight lows from 10.3°C to 12.6°C over the same span.

Is September a good time to visit Milton?▼

September is one of the warmer months of the year in Milton and a relatively wet time of year, so plan for around 23.2°C daytime highs and 11.1°C at night.

Is September the coldest month in Milton?▼

Not quite — September is the 9th coolest month in Milton, averaging 17.2°C.

What should I pack for Milton in September?▼

For September in Milton, pack light layers you can adjust through the day, with typical highs of 23.2°C and lows of 11.1°C. Bring an umbrella or light rain jacket too.

Is Milton humid in September?▼

Relative humidity in September averages 71% — moderately humid.

How windy is Milton in September?▼

Average wind speed in September is 2.6 m/s. The windiest September on record averaged 3.1 m/s (2010).

Which September had the most rainfall in Milton?▼

The wettest September on record was 1986 with 176 mm. On average, September sees 70 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 Milton 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.