Carlisle Weather in September (1981–2025)

📍 40.21°N, 77.21°W •
📊

September at a Glance in Carlisle

(1981–2025)
Avg High
🔥
25.1°C
Avg Low
❄️
12.8°C
Avg Temp
🌡️
19.0°C
Avg Rain
🌧️
105 mm
Avg Humidity
💧
70%
Avg Wind
🌬️
0.9 m/s
Avg Solar
☀️
4.1
kWh/m²/day
vs Annual
📈
+8.3°C
temp difference
🌤️Mild afternoons🌤️Cool mornings🌤️Fairly sunny🌧️Wet month🍃Light winds😊Comfortable humidity

Carlisle September Weather Overview

September is one of the warmer months of the year in Carlisle, with average highs near 25.1°C and lows around 12.8°C (mean 19°C). It is a relatively wet time of year, averaging 105 mm of rainfall and 70% relative humidity across the period.

Carlisle September Temperature History (1981–2025)

Range

September is one of the warmer months of the year in Carlisle. Across 45 years of records, the warmest September in Carlisle was 2019 — when the month averaged 21.9°C — while the coldest was 1984 at 16.9°C. Typical September days reach 25.1°C with nights near 12.8°C. The long-term trend is warming, about 0.5°C per decade.

1981–1985 vs 2021–2025

Avg Temp18.5°C→19.7°C+1.2°C
Max Temp25.3°C→25.7°C+0.4°C
Min Temp11.7°C→13.8°C+2.1°C

Trend (per decade)

Avg Temp+0.5°C/decade ↗
Max Temp+0.3°C/decade ↗
Min Temp+0.6°C/decade ↗

Distribution of Avg Temp

16.0°C–17.5°C5 yr (11%)
17.5°C–19.0°C20 yr (44%)
19.0°C–20.5°C14 yr (31%)
20.5°C–22.0°C6 yr (13%)

Carlisle September Rainfall History (1981–2025)

Range

September is a relatively wet time of year in Carlisle, averaging 105 mm of rainfall. The wettest September on record was 2011 with 307 mm, while the driest was 2005 at 13 mm.

Carlisle September Humidity History (1981–2025)

Range

Relative humidity in Carlisle during September averages 70%. The most humid September was 2018 at 88%, and the least humid was 1983 at 57%.

Carlisle September Solar History (1981–2025)

Range

September receives about 4.1 kWh/m²/day of solar energy in Carlisle. The sunniest September was 2007 at 5.1 kWh/m²/day, and the cloudiest was 2011 at 3.

Carlisle September Wind History (1981–2025)

Range

Average wind speed in Carlisle during September is 0.9 m/s. The windiest Septembers were 1996 and 1999 at 1 m/s, while the calmest were 2023, 2024 and 2025, among others at 0.8 m/s.

What September Feels Like in Carlisle

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

How September Ranks in Carlisle

🔥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 Carlisle Weather by Month

Carlisle September Averages by Decade

Metric1980s1990s2000s2010s2020sChange
Avg Temp18.5°C18.3°C18.8°C19.9°C19.6°C+1.1°C
Avg High25.0°C24.5°C24.9°C25.9°C25.6°C+0.6°C
Avg Low12.0°C12.1°C12.7°C13.8°C13.6°C+1.6°C
Avg Rain70 mm111 mm113 mm123 mm106 mm+36 mm

Extreme September Records in Carlisle

🔥Warmest September37.0°C2023
🧊Coldest September1.7°C2000
🌧️Wettest September307 mm2011
🏜️Driest September13 mm2005
🌬️Windiest September1 m/s1996

Key Insights for September

✅

September temperatures in Carlisle have risen by about 1.2°C between 1981–1985 and 2021–2025.

✅

September has ranged from a record low of 1.7°C (2000) to a record high of 37°C (2023).

✅

Rainfall in September is a relatively wet time of year, averaging 105 mm, with a wettest year of 307 mm.

✅

Daytime highs and overnight lows have shifted differently — highs rose about 0.3°C per decade while lows rose 0.6°C per decade, narrowing the gap between day and night.

Is September a Good Time to Visit Carlisle?

One of the best times to visit Carlisle

September is one of the best times to visit Carlisle. Expect days averaging 25.1°C and nights around 12.8°C (mean 19°C) — warmer than Carlisle's yearly average — with higher rainfall (105 mm), so conditions are generally comfortable for sightseeing and outdoor plans.

See Carlisle'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 →

Carlisle Weather in September — In Depth

☀️ September climate overview

September is one of the warmer months of the year in Carlisle, with average highs near 25.1°C and lows around 12.8°C (mean 19°C). It is a relatively wet time of year, averaging 105 mm of rainfall and 70% relative humidity across the period.

🌧️ Rain, humidity & wind in September

September averages 105 mm of rainfall in Carlisle, a relatively wet time of year compared with the rest of the year. The wettest September on record saw 307 mm (2011), and the driest just 13 mm (2005). Humidity sits around 70% and average wind speed is 0.9 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 1.2°C. Daytime highs moved from 25.3°C to 25.7°C and overnight lows from 11.7°C to 13.8°C over the same span.
September Weather in Carlisle, Year by Year
🔥 warmest❄️ coldest🌧️ wettest
YearAvg HighAvg TempAvg LowHottest DayColdest DayRainfallHumidityWindSolar
202527.5°C20.9°C14.3°C32.4°C8.4°C41 mm61%0.8 m/s4.4
202425.2°C19.5°C13.9°C29.8°C7.3°C87 mm74%0.8 m/s4.1
202326.2°C20.0°C13.8°C37.0°C7.3°C116 mm70%0.8 m/s4.3
202225.3°C19.4°C13.5°C32.4°C6.8°C97 mm72%0.8 m/s4.1
202124.3°C18.9°C13.4°C29.1°C8.0°C240 mm81%0.9 m/s4.3
202025.3°C18.9°C12.5°C30.3°C2.8°C56 mm68%0.8 m/s4.1
2019 🔥28.7°C21.9°C15.1°C35.5°C7.8°C25 mm64%0.8 m/s4.4
201824.3°C20.2°C16.2°C32.2°C8.4°C300 mm88%0.8 m/s3.1
201725.8°C19.5°C13.2°C32.9°C7.0°C45 mm70%0.8 m/s4.4
201627.8°C21.4°C15.0°C34.6°C8.3°C97 mm65%0.9 m/s4.5
201526.9°C20.6°C14.3°C34.5°C8.3°C88 mm67%0.8 m/s4.4
201425.6°C19.1°C12.7°C31.9°C5.7°C42 mm68%0.8 m/s4.4
201325.3°C18.4°C11.6°C34.1°C3.8°C37 mm64%0.8 m/s4.7
201224.3°C18.4°C12.6°C32.3°C4.5°C129 mm73%0.8 m/s4.2
2011 🌧️23.2°C18.7°C14.2°C31.8°C4.0°C307 mm87%0.8 m/s3
201027.3°C20.3°C13.4°C35.9°C8.3°C159 mm62%0.9 m/s4.5
200923.4°C18.0°C12.6°C29.2°C6.8°C74 mm74%0.9 m/s3.9
200824.9°C19.1°C13.2°C33.0°C7.7°C152 mm74%0.8 m/s4.2
200726.8°C20.0°C13.1°C33.3°C5.0°C37 mm67%0.8 m/s5.1
200622.5°C17.2°C11.9°C27.7°C5.1°C130 mm79%0.9 m/s3.4
200528.2°C21.2°C14.2°C32.6°C5.2°C13 mm61%0.8 m/s4.8
200424.5°C19.2°C13.8°C28.9°C5.9°C247 mm80%0.9 m/s4
200323.2°C18.1°C13.0°C28.7°C4.8°C197 mm83%0.9 m/s3.6
200227.0°C20.4°C13.7°C34.8°C7.7°C108 mm65%0.9 m/s4.3
200125.1°C17.9°C10.7°C31.7°C4.4°C66 mm61%0.9 m/s4.7
200023.4°C17.1°C10.8°C30.7°C1.7°C109 mm72%0.9 m/s4.2
199924.2°C18.3°C12.4°C31.5°C4.7°C195 mm73%1 m/s4.1
199828.2°C20.9°C13.7°C34.7°C4.8°C46 mm61%0.8 m/s4.6
199724.0°C17.7°C11.5°C32.3°C4.1°C110 mm68%0.9 m/s4.2
199622.5°C17.5°C12.6°C29.8°C6.7°C232 mm82%1 m/s3.7
199525.1°C18.5°C11.8°C32.0°C3.8°C52 mm61%0.8 m/s4.1
199423.2°C17.2°C11.3°C29.9°C5.2°C81 mm74%0.9 m/s4.2
199324.2°C18.5°C12.7°C32.4°C3.6°C150 mm73%0.9 m/s3.3
199223.8°C17.9°C11.9°C29.7°C2.9°C108 mm73%0.9 m/s3.8
199125.3°C18.5°C11.7°C34.7°C1.8°C78 mm63%0.8 m/s4.1
199024.2°C17.9°C11.6°C31.7°C2.3°C60 mm72%0.9 m/s3.9
198924.9°C18.9°C13.0°C33.6°C3.5°C61 mm71%0.9 m/s3.5
198824.0°C17.4°C10.8°C29.4°C5.4°C84 mm70%0.8 m/s4.1
198723.6°C18.2°C12.9°C27.9°C5.2°C165 mm79%0.8 m/s3.7
198625.7°C19.3°C12.9°C32.0°C3.5°C42 mm69%0.9 m/s3.9
198526.7°C19.7°C12.6°C34.2°C5.4°C57 mm61%0.8 m/s4.5
1984 ❄️23.8°C16.9°C10.1°C32.1°C3.8°C43 mm68%0.9 m/s4.5
198326.8°C19.5°C12.2°C35.5°C3.2°C45 mm57%0.9 m/s—
198225.4°C18.8°C12.3°C30.6°C6.7°C69 mm67%0.8 m/s—
198123.8°C17.7°C11.5°C31.3°C3.7°C65 mm70%0.9 m/s—

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

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Carlisle September Weather — FAQ

What is the average temperature in Carlisle in September?▼

The average high in September is around 25.1°C with lows near 12.8°C (mean 19°C), based on 45 years of NASA POWER data.

Does it rain a lot in Carlisle in September?▼

September averages 105 mm of rainfall in Carlisle, a relatively wet time of year. The wettest on record was 307 mm in 2011.

What was the hottest September on record in Carlisle?▼

The hottest September reached 37°C in 2023. The coldest dipped to 1.7°C in 2000.

Has September in Carlisle 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 1.2°C. Daytime highs moved from 25.3°C to 25.7°C and overnight lows from 11.7°C to 13.8°C over the same span.

Is September a good time to visit Carlisle?▼

September is one of the warmer months of the year in Carlisle and a relatively wet time of year, so plan for around 25.1°C daytime highs and 12.8°C at night.

Is September the coldest month in Carlisle?▼

Not quite — September is the 9th coolest month in Carlisle, averaging 19°C.

What should I pack for Carlisle in September?▼

For September in Carlisle, pack light layers you can adjust through the day, with typical highs of 25.1°C and lows of 12.8°C. Bring an umbrella or light rain jacket too.

Is Carlisle humid in September?▼

Relative humidity in September averages 70% — moderately humid.

How windy is Carlisle in September?▼

Average wind speed in September is 0.9 m/s. The windiest September on record averaged 1 m/s (1996).

Which September had the most rainfall in Carlisle?▼

The wettest September on record was 2011 with 307 mm. On average, September sees 105 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 Carlisle 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.