Auburn Weather in September (1981–2025)

📍 47.30°N, 122.20°W •
📊

September at a Glance in Auburn

(1981–2025)
Avg High
🔥
20.8°C
Avg Low
❄️
10.8°C
Avg Temp
🌡️
15.8°C
Avg Rain
🌧️
54 mm
Avg Humidity
💧
77%
Avg Wind
🌬️
0.6 m/s
Avg Solar
☀️
4
kWh/m²/day
vs Annual
📈
+5.2°C
temp difference
🌤️Mild afternoons🌤️Cool mornings🌤️Fairly sunny🌦️Some rain🍃Light winds💦Humid air

Auburn September Weather Overview

September is one of the warmer months of the year in Auburn, with average highs near 20.8°C and lows around 10.8°C (mean 15.8°C). It is one of the drier months, averaging 54 mm of rainfall and 77% relative humidity across the period.

Auburn September Temperature History (1981–2025)

Range

September is one of the warmer months of the year in Auburn. Across 45 years of records, the warmest September in Auburn was 1990 — when the month averaged 17.7°C — while the coldest was 1983 at 13.7°C. Typical September days reach 20.8°C with nights near 10.8°C. The long-term September temperature trend is broadly flat.

1981–1985 vs 2021–2025

Avg Temp14.8°C→15.7°C+0.9°C
Max Temp19.8°C→20.2°C+0.4°C
Min Temp9.7°C→11.1°C+1.4°C

Trend (per decade)

Avg Temp0°C/decade →
Max Temp-0.2°C/decade ↘
Min Temp+0.3°C/decade ↗

Distribution of Avg Temp

13.0°C–14.3°C2 yr (4%)
14.3°C–15.5°C15 yr (33%)
15.5°C–16.8°C19 yr (42%)
16.8°C–18.0°C9 yr (20%)

Auburn September Rainfall History (1981–2025)

Range

September is one of the drier months in Auburn, averaging 54 mm of rainfall. The wettest September on record was 2013 with 185 mm, while the driest was 2022 at 5 mm.

Auburn September Humidity History (1981–2025)

Range

Relative humidity in Auburn during September averages 77%. The most humid September was 2025 at 89%, and the least humid was 1989 at 68%.

Auburn September Solar History (1981–2025)

Range

September receives about 4 kWh/m²/day of solar energy in Auburn. The sunniest September was 1998 at 4.8 kWh/m²/day, and the cloudiest were 2010, 2013 and 2019 at 3.2.

Auburn September Wind History (1981–2025)

Range

Average wind speed in Auburn during September is 0.6 m/s. The windiest September was 1997 at 0.8 m/s, while the calmest were 1991, 1993 and 2025 at 0.5 m/s.

What September Feels Like in Auburn

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

How September Ranks in Auburn

🔥3rd warmest month of the year
🌵3rd driest month of the year
☀️6th sunniest month of the year

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

Explore Auburn Weather by Month

Auburn September Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp15.3°C16.3°C15.7°C15.8°C16.0°C+0.7°C
Avg High20.7°C21.6°C20.8°C20.3°C20.6°C-0.1°C
Avg Low10.0°C11.1°C10.6°C11.1°C11.4°C+1.4°C
Avg Rain56 mm39 mm44 mm71 mm63 mm+7 mm

Extreme September Records in Auburn

🔥Warmest September34.7°C1988
🧊Coldest September3.8°C2019
🌧️Wettest September185 mm2013
🏜️Driest September5 mm2022
🌬️Windiest September0.8 m/s1997

Key Insights for September

✅

September temperatures in Auburn have risen by about 0.9°C between 1981–1985 and 2021–2025.

✅

September has ranged from a record low of 3.8°C (2019) to a record high of 34.7°C (1988).

✅

Rainfall in September is one of the drier months, averaging 54 mm, with a wettest year of 185 mm.

✅

Daytime highs and overnight lows have shifted differently — highs fell about 0.2°C per decade while lows rose 0.3°C per decade, narrowing the gap between day and night.

Is September a Good Time to Visit Auburn?

One of the best times to visit Auburn

September is one of the best times to visit Auburn. Expect days averaging 20.8°C and nights around 10.8°C (mean 15.8°C) — warmer than Auburn's yearly average — with moderate rainfall (54 mm), so conditions are generally comfortable for sightseeing and outdoor plans.

See Auburn'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 →

Auburn Weather in September — In Depth

☀️ September climate overview

September is one of the warmer months of the year in Auburn, with average highs near 20.8°C and lows around 10.8°C (mean 15.8°C). It is one of the drier months, averaging 54 mm of rainfall and 77% relative humidity across the period.

🌧️ Rain, humidity & wind in September

September averages 54 mm of rainfall in Auburn, one of the drier months compared with the rest of the year. The wettest September on record saw 185 mm (2013), and the driest just 5 mm (2022). Humidity sits around 77% and average wind speed is 0.6 m/s, with solar radiation averaging 4 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 0.9°C. Daytime highs moved from 19.8°C to 20.2°C and overnight lows from 9.7°C to 11.1°C over the same span.
September Weather in Auburn, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
202518.4°C14.3°C10.2°C29.4°C6.7°C62 mm89%0.5 m/s4
202419.1°C14.8°C10.5°C32.6°C5.6°C54 mm86%0.6 m/s3.7
202320.7°C16.1°C11.4°C28.1°C6.7°C82 mm78%0.6 m/s3.9
202222.3°C17.4°C12.4°C28.8°C10.2°C5 mm76%0.6 m/s4.3
202120.7°C15.9°C11.2°C25.6°C8.0°C94 mm77%0.7 m/s3.8
202022.4°C17.5°C12.6°C30.8°C9.2°C80 mm78%0.7 m/s3.7
201920.1°C15.9°C11.6°C27.5°C3.8°C90 mm81%0.7 m/s3.2
201819.5°C14.9°C10.4°C26.9°C6.3°C54 mm81%0.7 m/s3.9
201721.2°C16.6°C11.9°C28.4°C7.9°C38 mm78%0.6 m/s3.8
201619.6°C14.9°C10.2°C25.6°C7.5°C43 mm78%0.6 m/s4
201519.5°C14.8°C10.1°C27.1°C6.1°C43 mm79%0.7 m/s3.8
201421.5°C16.7°C11.8°C28.4°C8.6°C66 mm77%0.6 m/s4.1
2013 🌧️20.4°C16.3°C12.1°C32.3°C7.2°C185 mm85%0.7 m/s3.2
201221.0°C15.7°C10.5°C28.1°C7.4°C5 mm76%0.6 m/s4.6
201121.4°C16.6°C11.7°C26.6°C8.9°C45 mm78%0.7 m/s4
201019.2°C15.1°C10.9°C26.4°C8.3°C139 mm87%0.6 m/s3.2
200922.0°C16.5°C11.0°C32.7°C5.4°C55 mm75%0.6 m/s4.1
200821.2°C15.8°C10.4°C27.3°C7.2°C20 mm75%0.6 m/s4.2
200719.1°C14.7°C10.3°C28.2°C5.8°C59 mm80%0.6 m/s3.7
200621.6°C16.2°C10.8°C30.9°C7.3°C32 mm73%0.6 m/s4.4
200519.6°C14.8°C9.9°C24.7°C6.8°C55 mm77%0.6 m/s4.2
200419.2°C15.0°C10.7°C22.9°C7.2°C81 mm83%0.7 m/s3.6
200322.6°C17.0°C11.5°C30.9°C7.3°C34 mm72%0.6 m/s4.2
200220.8°C15.5°C10.2°C25.6°C5.8°C21 mm74%0.6 m/s4.3
200121.5°C16.2°C10.9°C26.4°C7.2°C20 mm75%0.6 m/s4
200020.3°C15.4°C10.5°C28.7°C5.8°C67 mm77%0.6 m/s3.9
199920.9°C15.2°C9.5°C29.1°C5.9°C11 mm75%0.6 m/s4.7
199822.2°C16.8°C11.5°C29.0°C9.2°C17 mm76%0.6 m/s4.8
199721.3°C16.7°C12.2°C30.1°C9.0°C122 mm82%0.8 m/s3.8
199618.5°C14.3°C10.2°C25.0°C4.8°C74 mm81%0.6 m/s3.6
199522.5°C17.3°C12.2°C27.5°C7.3°C53 mm76%0.6 m/s3.9
199422.6°C17.3°C12.0°C28.1°C8.2°C42 mm75%0.6 m/s4.1
199322.4°C16.5°C10.6°C29.5°C6.0°C6 mm70%0.5 m/s4.7
199220.3°C14.9°C9.6°C26.0°C6.0°C59 mm73%0.6 m/s4.1
199122.0°C16.6°C11.1°C27.6°C7.1°C5 mm75%0.5 m/s4.4
1990 🔥23.5°C17.7°C11.9°C29.8°C8.0°C7 mm73%0.6 m/s4
198923.2°C17.0°C10.8°C28.6°C8.1°C11 mm68%0.6 m/s4.5
198821.6°C15.9°C10.3°C34.7°C6.0°C71 mm71%0.6 m/s4
198723.1°C17.1°C11.2°C30.2°C7.0°C17 mm69%0.6 m/s4.2
198619.2°C14.3°C9.5°C27.1°C6.6°C72 mm77%0.6 m/s3.5
198519.4°C14.2°C9.1°C24.2°C5.6°C65 mm73%0.7 m/s3.8
198419.4°C14.4°C9.4°C23.3°C5.7°C57 mm76%0.7 m/s3.7
1983 ❄️18.6°C13.7°C8.8°C24.2°C3.9°C66 mm79%0.7 m/s—
198221.1°C15.9°C10.7°C29.1°C6.3°C60 mm77%0.6 m/s—
198120.7°C15.6°C10.5°C31.4°C6.7°C83 mm77%0.7 m/s—

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

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Auburn September Weather — FAQ

What is the average temperature in Auburn in September?▼

The average high in September is around 20.8°C with lows near 10.8°C (mean 15.8°C), based on 45 years of NASA POWER data.

Does it rain a lot in Auburn in September?▼

September averages 54 mm of rainfall in Auburn, one of the drier months. The wettest on record was 185 mm in 2013.

What was the hottest September on record in Auburn?▼

The hottest September reached 34.7°C in 1988. The coldest dipped to 3.8°C in 2019.

Has September in Auburn 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 0.9°C. Daytime highs moved from 19.8°C to 20.2°C and overnight lows from 9.7°C to 11.1°C over the same span.

Is September a good time to visit Auburn?▼

September is one of the warmer months of the year in Auburn and one of the drier months, so plan for around 20.8°C daytime highs and 10.8°C at night.

Is September the coldest month in Auburn?▼

Not quite — September is the 10th coolest month in Auburn, averaging 15.8°C.

What should I pack for Auburn in September?▼

For September in Auburn, pack light layers you can adjust through the day, with typical highs of 20.8°C and lows of 10.8°C. Bring an umbrella or light rain jacket too.

Is Auburn humid in September?▼

Relative humidity in September averages 77% — quite humid.

How windy is Auburn in September?▼

Average wind speed in September is 0.6 m/s. The windiest September on record averaged 0.8 m/s (1997).

Which September had the most rainfall in Auburn?▼

The wettest September on record was 2013 with 185 mm. On average, September sees 54 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 Auburn 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.