September is one of the cooler months of the year in Ayr, with average highs near 25.9°C and lows around 21.1°C (mean 23.5°C). It is one of the drier months, averaging 9 mm of rainfall and 70% relative humidity across the period.
September is one of the cooler months of the year in Ayr. Across 45 years of records, the warmest September in Ayr was 2010 — when the month averaged 25.1°C — while the coldest was 1990 at 21.7°C. Typical September days reach 25.9°C with nights near 21.1°C. The long-term September temperature trend is broadly flat.
September is one of the drier months in Ayr, averaging 9 mm of rainfall. The wettest September on record was 2010 with 63 mm, while the driest was 1989 at 0 mm.
Relative humidity in Ayr during September averages 70%. The most humid September was 2010 at 79%, and the least humid was 1991 at 61%.
September receives about 6 kWh/m²/day of solar energy in Ayr. The sunniest September was 2019 at 6.5 kWh/m²/day, and the cloudiest was 2010 at 5.1.
Average wind speed in Ayr during September is 4.6 m/s. The windiest September was 1981 at 5.8 m/s, while the calmest was 1984 at 3.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 23.3°C | 23.2°C | 23.5°C | 23.7°C | 23.8°C | +0.5°C |
| Avg High | 25.9°C | 25.6°C | 26.0°C | 25.9°C | 26.1°C | +0.2°C |
| Avg Low | 20.8°C | 20.8°C | 21.1°C | 21.4°C | 21.5°C | +0.7°C |
| Avg Rain | 9 mm | 9 mm | 8 mm | 11 mm | 9 mm | +0 mm |
September temperatures in Ayr have risen by about 0.7°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 13.3°C (1990) to a record high of 32.5°C (1989).
Rainfall in September is one of the drier months, averaging 9 mm, with a wettest year of 63 mm.
One of the best times to visit Ayr
September is one of the best times to visit Ayr. Expect days averaging 25.9°C and nights around 21.1°C (mean 23.5°C) — cooler than Ayr's yearly average — with low rainfall (9 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 26.4°C | 24.1°C | 21.8°C | 29.1°C | 18.8°C | 10 mm | 71% | 5 m/s | 5.9 |
| 2024 | 26.6°C | 24.3°C | 22.0°C | 32.2°C | 19.4°C | 5 mm | 70% | 5 m/s | 5.6 |
| 2023 | 26.0°C | 23.8°C | 21.5°C | 28.9°C | 20.0°C | 7 mm | 70% | 5.5 m/s | 6.1 |
| 2022 | 26.4°C | 24.1°C | 21.8°C | 28.9°C | 16.6°C | 22 mm | 75% | 4.1 m/s | 6 |
| 2021 | 25.3°C | 23.0°C | 20.7°C | 30.4°C | 16.7°C | 4 mm | 70% | 5.2 m/s | 6.1 |
| 2020 | 25.7°C | 23.5°C | 21.3°C | 29.0°C | 19.1°C | 5 mm | 74% | 5.5 m/s | 5.9 |
| 2019 | 25.7°C | 22.9°C | 20.1°C | 28.3°C | 17.2°C | 1 mm | 65% | 4.3 m/s | 6.5 |
| 2018 | 26.1°C | 23.7°C | 21.3°C | 30.6°C | 17.9°C | 3 mm | 68% | 4.7 m/s | 6.4 |
| 2017 | 26.2°C | 23.9°C | 21.6°C | 30.2°C | 20.5°C | 5 mm | 68% | 4.2 m/s | 6.2 |
| 2016 | 26.7°C | 24.7°C | 22.6°C | 31.0°C | 20.2°C | 12 mm | 75% | 4.3 m/s | 5.6 |
| 2015 | 26.0°C | 23.6°C | 21.2°C | 29.7°C | 17.8°C | 5 mm | 66% | 4.6 m/s | 6.2 |
| 2014 | 25.3°C | 23.1°C | 20.9°C | 28.0°C | 17.8°C | 11 mm | 70% | 4 m/s | 6.1 |
| 2013 | 26.3°C | 24.1°C | 21.8°C | 28.7°C | 20.1°C | 2 mm | 72% | 4.6 m/s | 6.2 |
| 2012 | 25.4°C | 23.2°C | 21.0°C | 26.9°C | 18.9°C | 5 mm | 71% | 4.3 m/s | 6.1 |
| 2011 | 24.8°C | 22.2°C | 19.7°C | 28.2°C | 15.7°C | 2 mm | 69% | 5 m/s | 6 |
| 2010 🔥 🌧️ | 27.0°C | 25.1°C | 23.3°C | 28.9°C | 20.4°C | 63 mm | 79% | 4.4 m/s | 5.1 |
| 2009 | 27.0°C | 24.5°C | 21.9°C | 29.6°C | 19.4°C | 3 mm | 65% | 4.2 m/s | 6.1 |
| 2008 | 25.6°C | 23.4°C | 21.1°C | 27.6°C | 18.3°C | 13 mm | 73% | 4.7 m/s | 5.7 |
| 2007 | 25.6°C | 23.1°C | 20.6°C | 28.1°C | 18.8°C | 16 mm | 71% | 3.9 m/s | 6.1 |
| 2006 | 25.2°C | 22.6°C | 20.1°C | 27.4°C | 15.7°C | 23 mm | 69% | 5.4 m/s | 5.9 |
| 2005 | 25.8°C | 23.5°C | 21.1°C | 28.5°C | 19.5°C | 2 mm | 69% | 4.3 m/s | 6 |
| 2004 | 25.3°C | 23.0°C | 20.8°C | 27.1°C | 17.6°C | 12 mm | 67% | 4.8 m/s | 6 |
| 2003 | 26.5°C | 23.9°C | 21.3°C | 31.4°C | 17.9°C | 1 mm | 63% | 4.2 m/s | 6.4 |
| 2002 | 26.2°C | 23.6°C | 21.1°C | 29.7°C | 18.7°C | 2 mm | 68% | 4 m/s | 6.4 |
| 2001 | 26.5°C | 24.1°C | 21.7°C | 31.5°C | 19.4°C | 6 mm | 69% | 5.1 m/s | 6.2 |
| 2000 | 26.3°C | 23.7°C | 21.1°C | 31.6°C | 18.7°C | 1 mm | 66% | 4.7 m/s | 6.2 |
| 1999 | 25.3°C | 22.9°C | 20.4°C | 29.5°C | 18.4°C | 7 mm | 72% | 5.2 m/s | 6.1 |
| 1998 | 25.7°C | 23.8°C | 22.0°C | 28.4°C | 19.3°C | 19 mm | 79% | 4.7 m/s | 5.7 |
| 1997 | 25.9°C | 23.5°C | 21.2°C | 28.9°C | 18.4°C | 5 mm | 73% | 4.3 m/s | 6 |
| 1996 | 25.7°C | 22.9°C | 20.2°C | 29.5°C | 14.9°C | 11 mm | 64% | 4.4 m/s | 6.4 |
| 1995 | 25.2°C | 22.9°C | 20.6°C | 29.3°C | 15.9°C | 2 mm | 71% | 4.3 m/s | 6 |
| 1994 | 25.0°C | 22.6°C | 20.1°C | 29.1°C | 17.7°C | 3 mm | 69% | 4.2 m/s | 6.3 |
| 1993 | 25.3°C | 23.3°C | 21.3°C | 27.2°C | 19.8°C | 22 mm | 72% | 5 m/s | 5.8 |
| 1992 | 26.9°C | 24.7°C | 22.6°C | 29.3°C | 19.5°C | 20 mm | 71% | 4.1 m/s | 5.5 |
| 1991 | 26.8°C | 24.0°C | 21.2°C | 29.9°C | 16.5°C | 1 mm | 61% | 4.1 m/s | 6.4 |
| 1990 ❄️ | 24.4°C | 21.7°C | 18.9°C | 26.1°C | 13.3°C | 2 mm | 67% | 5.4 m/s | 6.1 |
| 1989 | 25.9°C | 23.2°C | 20.4°C | 32.5°C | 14.7°C | 0 mm | 69% | 4.2 m/s | 6.2 |
| 1988 | 26.1°C | 23.3°C | 20.6°C | 29.2°C | 16.1°C | 2 mm | 70% | 4.5 m/s | 6 |
| 1987 | 25.4°C | 23.2°C | 20.9°C | 26.6°C | 17.2°C | 3 mm | 68% | 5 m/s | 5.7 |
| 1986 | 26.6°C | 24.0°C | 21.5°C | 32.3°C | 18.9°C | 19 mm | 69% | 4.5 m/s | 5.9 |
| 1985 | 25.9°C | 22.9°C | 19.9°C | 31.1°C | 14.9°C | 4 mm | 64% | 4.4 m/s | 6.3 |
| 1984 | 26.1°C | 23.6°C | 21.0°C | 28.9°C | 16.6°C | 26 mm | 68% | 3.7 m/s | 5.9 |
| 1983 | 26.3°C | 24.1°C | 22.0°C | 28.8°C | 19.1°C | 4 mm | 74% | 4.4 m/s | — |
| 1982 | 24.9°C | 22.3°C | 19.8°C | 32.2°C | 17.5°C | 15 mm | 69% | 4.4 m/s | — |
| 1981 | 25.6°C | 23.3°C | 21.0°C | 29.3°C | 17.2°C | 4 mm | 68% | 5.8 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 25.9°C with lows near 21.1°C (mean 23.5°C), based on 45 years of NASA POWER data.
September averages 9 mm of rainfall in Ayr, one of the drier months. The wettest on record was 63 mm in 2010.
The hottest September reached 32.5°C in 1989. The coldest dipped to 13.3°C in 1990.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 0.7°C. Daytime highs moved from 25.8°C to 26.1°C and overnight lows from 20.7°C to 21.6°C over the same span.
September is one of the cooler months of the year in Ayr and one of the drier months, so plan for around 25.9°C daytime highs and 21.1°C at night.
Not quite — September is the 4th coolest month in Ayr, averaging 23.5°C.
For September in Ayr, pack light layers you can adjust through the day, with typical highs of 25.9°C and lows of 21.1°C.
Relative humidity in September averages 70% — moderately humid.
Average wind speed in September is 4.6 m/s. The windiest September on record averaged 5.8 m/s (1981).
The wettest September on record was 2010 with 63 mm. On average, September sees 9 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Ayr 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.
