September is one of the warmer months of the year in Kilwinning, with average highs near 14.8°C and lows around 10.5°C (mean 12.7°C). It is about average for rainfall, averaging 106 mm of rainfall and 87% relative humidity across the period.
September is one of the warmer months of the year in Kilwinning. Across 45 years of records, the warmest September in Kilwinning was 2006 — when the month averaged 14.4°C — while the coldest was 1986 at 10.8°C. Typical September days reach 14.8°C with nights near 10.5°C. The long-term trend is warming, about 0.3°C per decade.
September is about average for rainfall in Kilwinning, averaging 106 mm of rainfall. The wettest September on record was 1981 with 201 mm, while the driest was 2014 at 17 mm.
Relative humidity in Kilwinning during September averages 87%. The most humid September was 1985 at 90%, and the least humid was 1991 at 84%.
September receives about 2.6 kWh/m²/day of solar energy in Kilwinning. The sunniest September was 1991 at 3.1 kWh/m²/day, and the cloudiest was 2000 at 2.1.
Average wind speed in Kilwinning during September is 4.6 m/s. The windiest Septembers were 1983, 2004 and 2011 at 5.7 m/s, while the calmest was 2014 at 3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 11.9°C | 12.4°C | 13.0°C | 12.6°C | 13.4°C | +1.5°C |
| Avg High | 13.9°C | 14.7°C | 15.1°C | 14.7°C | 15.7°C | +1.8°C |
| Avg Low | 9.9°C | 10.2°C | 11.0°C | 10.6°C | 11.0°C | +1.1°C |
| Avg Rain | 130 mm | 90 mm | 106 mm | 104 mm | 102 mm | -28 mm |
September temperatures in Kilwinning have risen by about 1.3°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 4.4°C (2007) to a record high of 23.1°C (2023).
Rainfall in September is about average for rainfall, averaging 106 mm, with a wettest year of 201 mm.
One of the best times to visit Kilwinning
September is one of the best times to visit Kilwinning. Expect days averaging 14.8°C and nights around 10.5°C (mean 12.7°C) — warmer than Kilwinning's yearly average — with higher rainfall (106 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 | 15.1°C | 13.0°C | 10.9°C | 17.1°C | 7.6°C | 107 mm | 85% | 4.9 m/s | 2.6 |
| 2024 | 15.0°C | 12.4°C | 9.8°C | 20.8°C | 6.5°C | 53 mm | 86% | 4.3 m/s | 2.8 |
| 2023 | 16.8°C | 14.3°C | 11.9°C | 23.1°C | 8.6°C | 143 mm | 87% | 4.5 m/s | 2.8 |
| 2022 | 15.9°C | 13.6°C | 11.2°C | 19.2°C | 7.0°C | 132 mm | 86% | 4.3 m/s | 2.9 |
| 2021 | 16.7°C | 14.3°C | 12.0°C | 21.6°C | 9.2°C | 77 mm | 88% | 3.5 m/s | 2.4 |
| 2020 | 14.8°C | 12.6°C | 10.4°C | 18.2°C | 4.6°C | 96 mm | 87% | 4.6 m/s | 2.7 |
| 2019 | 14.8°C | 12.8°C | 10.8°C | 18.1°C | 8.8°C | 123 mm | 87% | 4.5 m/s | 2.7 |
| 2018 | 13.9°C | 11.9°C | 9.9°C | 17.7°C | 7.1°C | 103 mm | 85% | 5.5 m/s | 2.6 |
| 2017 | 14.4°C | 12.5°C | 10.7°C | 16.7°C | 7.7°C | 137 mm | 88% | 4.6 m/s | 2.4 |
| 2016 | 15.6°C | 13.7°C | 11.9°C | 18.7°C | 9.0°C | 123 mm | 88% | 5.1 m/s | 2.5 |
| 2015 | 14.4°C | 12.0°C | 9.5°C | 17.0°C | 8.2°C | 44 mm | 87% | 3.9 m/s | 3 |
| 2014 | 16.0°C | 13.5°C | 11.0°C | 18.6°C | 8.6°C | 17 mm | 88% | 3 m/s | 2.9 |
| 2013 | 14.3°C | 12.3°C | 10.2°C | 17.4°C | 7.7°C | 97 mm | 88% | 4.6 m/s | 2.5 |
| 2012 | 13.5°C | 11.6°C | 9.8°C | 16.6°C | 5.5°C | 132 mm | 86% | 5.6 m/s | 2.5 |
| 2011 | 14.7°C | 12.9°C | 11.1°C | 18.3°C | 8.8°C | 157 mm | 88% | 5.7 m/s | 2.5 |
| 2010 | 15.1°C | 12.9°C | 10.7°C | 18.2°C | 4.9°C | 112 mm | 86% | 4.8 m/s | 2.8 |
| 2009 | 14.6°C | 12.8°C | 11.0°C | 16.8°C | 8.4°C | 68 mm | 88% | 4.7 m/s | 2.6 |
| 2008 | 14.5°C | 12.5°C | 10.5°C | 16.2°C | 7.9°C | 120 mm | 88% | 4.1 m/s | 2.3 |
| 2007 | 14.5°C | 12.2°C | 10.0°C | 17.4°C | 4.4°C | 71 mm | 87% | 4.6 m/s | 2.6 |
| 2006 🔥 | 16.4°C | 14.4°C | 12.3°C | 19.3°C | 9.1°C | 164 mm | 89% | 4.5 m/s | 2.5 |
| 2005 | 15.2°C | 13.3°C | 11.3°C | 20.5°C | 6.6°C | 96 mm | 87% | 5.3 m/s | 2.4 |
| 2004 | 14.9°C | 13.1°C | 11.3°C | 18.4°C | 7.9°C | 136 mm | 88% | 5.7 m/s | 2.7 |
| 2003 | 15.2°C | 13.1°C | 11.1°C | 18.0°C | 6.8°C | 89 mm | 86% | 3.8 m/s | 2.7 |
| 2002 | 15.5°C | 13.2°C | 10.9°C | 18.5°C | 7.4°C | 59 mm | 88% | 3.2 m/s | 2.7 |
| 2001 | 14.6°C | 12.3°C | 10.0°C | 16.9°C | 6.4°C | 76 mm | 88% | 4.7 m/s | 2.6 |
| 2000 | 15.4°C | 13.3°C | 11.2°C | 18.7°C | 9.0°C | 179 mm | 88% | 4.4 m/s | 2.1 |
| 1999 | 15.6°C | 13.6°C | 11.5°C | 19.4°C | 8.8°C | 148 mm | 88% | 4.7 m/s | 2.4 |
| 1998 | 15.4°C | 13.2°C | 11.0°C | 19.8°C | 6.7°C | 89 mm | 89% | 4.1 m/s | 2.8 |
| 1997 | 14.8°C | 12.4°C | 10.1°C | 17.6°C | 6.8°C | 78 mm | 86% | 4.7 m/s | 2.8 |
| 1996 | 15.4°C | 12.8°C | 10.2°C | 20.3°C | 6.6°C | 51 mm | 86% | 4.2 m/s | 3 |
| 1995 | 14.9°C | 12.6°C | 10.3°C | 17.1°C | 7.0°C | 96 mm | 86% | 4 m/s | 2.7 |
| 1994 | 13.6°C | 11.5°C | 9.4°C | 17.1°C | 6.8°C | 72 mm | 86% | 4.1 m/s | 2.5 |
| 1993 | 14.0°C | 11.5°C | 9.1°C | 17.5°C | 5.5°C | 70 mm | 85% | 4.4 m/s | 2.6 |
| 1992 | 13.6°C | 11.7°C | 9.9°C | 17.5°C | 7.5°C | 138 mm | 87% | 4.9 m/s | 2.5 |
| 1991 | 15.5°C | 12.9°C | 10.4°C | 21.8°C | 5.6°C | 78 mm | 84% | 4.4 m/s | 3.1 |
| 1990 | 13.8°C | 11.7°C | 9.6°C | 18.5°C | 5.5°C | 81 mm | 85% | 4.9 m/s | 2.6 |
| 1989 | 14.4°C | 12.2°C | 9.9°C | 16.5°C | 7.7°C | 85 mm | 86% | 4.5 m/s | 2.4 |
| 1988 | 13.5°C | 11.8°C | 10.1°C | 17.4°C | 5.9°C | 130 mm | 87% | 5.3 m/s | 2.4 |
| 1987 | 13.6°C | 11.8°C | 9.9°C | 16.5°C | 6.2°C | 120 mm | 85% | 5.2 m/s | 2.8 |
| 1986 ❄️ | 13.0°C | 10.8°C | 8.5°C | 16.2°C | 4.8°C | 38 mm | 84% | 4.1 m/s | 2.9 |
| 1985 | 14.2°C | 12.3°C | 10.4°C | 17.6°C | 6.9°C | 193 mm | 90% | 4.4 m/s | 2.3 |
| 1984 | 14.0°C | 11.9°C | 9.9°C | 18.3°C | 6.8°C | 134 mm | 85% | 4.4 m/s | 2.4 |
| 1983 | 13.8°C | 11.9°C | 10.0°C | 16.5°C | 6.4°C | 123 mm | 85% | 5.7 m/s | — |
| 1982 | 14.0°C | 11.9°C | 9.7°C | 18.1°C | 7.0°C | 146 mm | 86% | 5.3 m/s | — |
| 1981 🌧️ | 14.9°C | 12.9°C | 11.0°C | 18.5°C | 8.7°C | 201 mm | 86% | 5 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 14.8°C with lows near 10.5°C (mean 12.7°C), based on 45 years of NASA POWER data.
September averages 106 mm of rainfall in Kilwinning, about average for rainfall. The wettest on record was 201 mm in 1981.
The hottest September reached 23.1°C in 2023. The coldest dipped to 4.4°C in 2007.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 1.3°C. Daytime highs moved from 14.2°C to 15.9°C and overnight lows from 10.2°C to 11.2°C over the same span.
September is one of the warmer months of the year in Kilwinning and about average for rainfall, so plan for around 14.8°C daytime highs and 10.5°C at night.
Not quite — September is the 10th coolest month in Kilwinning, averaging 12.7°C.
For September in Kilwinning, pack light layers you can adjust through the day, with typical highs of 14.8°C and lows of 10.5°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 87% — quite humid.
Average wind speed in September is 4.6 m/s. The windiest September on record averaged 5.7 m/s (1983).
The wettest September on record was 1981 with 201 mm. On average, September sees 106 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 Kilwinning 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.
