September is one of the warmer months of the year in Glasgow, with average highs near 14.4°C and lows around 8.2°C (mean 11.3°C). It is about average for rainfall, averaging 112 mm of rainfall and 89% relative humidity across the period.
September is one of the warmer months of the year in Glasgow. Across 45 years of records, the warmest September in Glasgow was 2006 — when the month averaged 13.4°C — while the coldest was 1986 at 9.4°C. Typical September days reach 14.4°C with nights near 8.2°C. The long-term trend is warming, about 0.3°C per decade.
September is about average for rainfall in Glasgow, averaging 112 mm of rainfall. The wettest September on record was 1981 with 199 mm, while the driest was 2014 at 26 mm.
Relative humidity in Glasgow during September averages 89%. The most humid September was 1985 at 92%, and the least humid was 1991 at 86%.
September receives about 2.6 kWh/m²/day of solar energy in Glasgow. The sunniest September was 1991 at 3.1 kWh/m²/day, and the cloudiest was 2000 at 2.1.
Average wind speed in Glasgow during September is 3.4 m/s. The windiest September was 2012 at 4.4 m/s, while the calmest were 2002 and 2014 at 2.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 10.6°C | 11.1°C | 11.7°C | 11.4°C | 12.0°C | +1.4°C |
| Avg High | 13.5°C | 14.3°C | 14.7°C | 14.3°C | 15.4°C | +1.9°C |
| Avg Low | 7.6°C | 7.9°C | 8.7°C | 8.4°C | 8.7°C | +1.1°C |
| Avg Rain | 140 mm | 96 mm | 113 mm | 108 mm | 99 mm | -40 mm |
September temperatures in Glasgow have risen by about 1.5°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 0.5°C (2007) to a record high of 24.3°C (2023).
Rainfall in September is about average for rainfall, averaging 112 mm, with a wettest year of 199 mm.
One of the best times to visit Glasgow
September is one of the best times to visit Glasgow. Expect days averaging 14.4°C and nights around 8.2°C (mean 11.3°C) — warmer than Glasgow's yearly average — with higher rainfall (112 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 | 14.6°C | 11.5°C | 8.3°C | 17.4°C | 3.0°C | 105 mm | 88% | 3.4 m/s | 2.6 |
| 2024 | 14.6°C | 11.0°C | 7.4°C | 20.7°C | 3.1°C | 51 mm | 89% | 3.1 m/s | 2.8 |
| 2023 | 16.5°C | 13.1°C | 9.8°C | 24.3°C | 5.3°C | 140 mm | 89% | 3.5 m/s | 2.8 |
| 2022 | 15.7°C | 12.1°C | 8.5°C | 20.3°C | 3.7°C | 114 mm | 88% | 3.1 m/s | 2.9 |
| 2021 | 16.6°C | 13.3°C | 10.0°C | 22.9°C | 6.2°C | 88 mm | 89% | 2.8 m/s | 2.4 |
| 2020 | 14.4°C | 11.2°C | 8.0°C | 18.9°C | 0.8°C | 98 mm | 89% | 3.6 m/s | 2.7 |
| 2019 | 14.5°C | 11.5°C | 8.4°C | 18.7°C | 5.2°C | 121 mm | 90% | 3.3 m/s | 2.7 |
| 2018 | 13.4°C | 10.5°C | 7.6°C | 18.5°C | 3.5°C | 127 mm | 88% | 4.2 m/s | 2.6 |
| 2017 | 14.0°C | 11.3°C | 8.6°C | 16.7°C | 5.6°C | 133 mm | 91% | 3.1 m/s | 2.4 |
| 2016 | 15.2°C | 12.6°C | 10.0°C | 19.9°C | 6.7°C | 149 mm | 90% | 3.9 m/s | 2.5 |
| 2015 | 14.5°C | 10.8°C | 7.1°C | 17.5°C | 4.7°C | 46 mm | 88% | 2.6 m/s | 3 |
| 2014 | 16.0°C | 12.6°C | 9.2°C | 19.3°C | 5.4°C | 26 mm | 89% | 2.3 m/s | 2.9 |
| 2013 | 14.0°C | 11.0°C | 7.9°C | 17.5°C | 4.8°C | 82 mm | 90% | 3.4 m/s | 2.5 |
| 2012 | 12.6°C | 10.0°C | 7.3°C | 16.5°C | 1.9°C | 109 mm | 90% | 4.4 m/s | 2.5 |
| 2011 | 14.3°C | 11.8°C | 9.3°C | 19.5°C | 5.6°C | 170 mm | 91% | 4.2 m/s | 2.5 |
| 2010 | 14.7°C | 11.5°C | 8.4°C | 18.8°C | 1.8°C | 116 mm | 89% | 3.5 m/s | 2.8 |
| 2009 | 14.2°C | 11.6°C | 9.1°C | 16.8°C | 6.2°C | 95 mm | 90% | 3.7 m/s | 2.6 |
| 2008 | 14.0°C | 11.2°C | 8.3°C | 16.3°C | 5.2°C | 122 mm | 90% | 3 m/s | 2.3 |
| 2007 | 13.9°C | 10.7°C | 7.4°C | 18.5°C | 0.5°C | 66 mm | 90% | 3.5 m/s | 2.6 |
| 2006 🔥 | 16.5°C | 13.4°C | 10.2°C | 20.4°C | 6.4°C | 187 mm | 90% | 3.2 m/s | 2.5 |
| 2005 | 14.9°C | 12.1°C | 9.2°C | 22.2°C | 3.0°C | 110 mm | 89% | 4.1 m/s | 2.4 |
| 2004 | 14.5°C | 11.8°C | 9.0°C | 19.5°C | 4.7°C | 141 mm | 90% | 4.3 m/s | 2.7 |
| 2003 | 14.8°C | 11.6°C | 8.4°C | 18.2°C | 3.5°C | 91 mm | 89% | 2.8 m/s | 2.7 |
| 2002 | 15.3°C | 11.9°C | 8.5°C | 18.9°C | 4.6°C | 48 mm | 90% | 2.3 m/s | 2.7 |
| 2001 | 14.3°C | 11.0°C | 7.7°C | 16.6°C | 4.1°C | 86 mm | 89% | 3.5 m/s | 2.6 |
| 2000 | 14.8°C | 11.8°C | 8.9°C | 18.7°C | 5.0°C | 184 mm | 90% | 3.2 m/s | 2.1 |
| 1999 | 15.6°C | 12.5°C | 9.4°C | 20.4°C | 5.9°C | 137 mm | 90% | 3.5 m/s | 2.4 |
| 1998 | 15.3°C | 12.3°C | 9.3°C | 21.4°C | 3.5°C | 103 mm | 91% | 2.9 m/s | 2.8 |
| 1997 | 14.2°C | 10.9°C | 7.6°C | 17.3°C | 3.0°C | 81 mm | 88% | 3.5 m/s | 2.8 |
| 1996 | 15.2°C | 11.7°C | 8.3°C | 20.0°C | 2.9°C | 62 mm | 88% | 3.3 m/s | 3 |
| 1995 | 14.6°C | 11.2°C | 7.8°C | 17.4°C | 2.7°C | 117 mm | 88% | 2.9 m/s | 2.7 |
| 1994 | 13.3°C | 10.1°C | 6.9°C | 17.7°C | 3.6°C | 68 mm | 88% | 3.1 m/s | 2.5 |
| 1993 | 13.6°C | 10.2°C | 6.7°C | 19.5°C | 1.5°C | 61 mm | 88% | 3.2 m/s | 2.6 |
| 1992 | 13.1°C | 10.4°C | 7.7°C | 18.6°C | 4.5°C | 159 mm | 90% | 3.8 m/s | 2.5 |
| 1991 | 15.2°C | 11.6°C | 7.9°C | 22.7°C | 2.6°C | 92 mm | 86% | 3.4 m/s | 3.1 |
| 1990 | 13.3°C | 10.2°C | 7.2°C | 18.5°C | 1.4°C | 84 mm | 88% | 3.7 m/s | 2.6 |
| 1989 | 14.0°C | 10.8°C | 7.5°C | 16.3°C | 4.8°C | 101 mm | 88% | 3.4 m/s | 2.4 |
| 1988 | 13.2°C | 10.7°C | 8.1°C | 19.3°C | 1.6°C | 133 mm | 90% | 4.1 m/s | 2.4 |
| 1987 | 13.1°C | 10.5°C | 7.9°C | 16.9°C | 3.5°C | 137 mm | 88% | 4 m/s | 2.8 |
| 1986 ❄️ | 12.7°C | 9.4°C | 6.0°C | 16.4°C | 0.6°C | 46 mm | 87% | 3.3 m/s | 2.9 |
| 1985 | 13.5°C | 10.9°C | 8.3°C | 18.2°C | 3.5°C | 199 mm | 92% | 3.5 m/s | 2.3 |
| 1984 | 13.4°C | 10.4°C | 7.4°C | 17.6°C | 3.9°C | 136 mm | 87% | 3 m/s | 2.4 |
| 1983 | 13.2°C | 10.4°C | 7.6°C | 16.5°C | 2.3°C | 149 mm | 88% | 4.3 m/s | — |
| 1982 | 13.5°C | 10.5°C | 7.4°C | 19.2°C | 3.5°C | 158 mm | 88% | 4.2 m/s | — |
| 1981 🌧️ | 14.5°C | 11.5°C | 8.6°C | 19.0°C | 6.1°C | 199 mm | 88% | 3.8 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 14.4°C with lows near 8.2°C (mean 11.3°C), based on 45 years of NASA POWER data.
September averages 112 mm of rainfall in Glasgow, about average for rainfall. The wettest on record was 199 mm in 1981.
The hottest September reached 24.3°C in 2023. The coldest dipped to 0.5°C in 2007.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 1.5°C. Daytime highs moved from 13.6°C to 15.6°C and overnight lows from 7.9°C to 8.8°C over the same span.
September is one of the warmer months of the year in Glasgow and about average for rainfall, so plan for around 14.4°C daytime highs and 8.2°C at night.
Not quite — September is the 9th coolest month in Glasgow, averaging 11.3°C.
For September in Glasgow, pack light layers you can adjust through the day, with typical highs of 14.4°C and lows of 8.2°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 89% — quite humid.
Average wind speed in September is 3.4 m/s. The windiest September on record averaged 4.4 m/s (2012).
The wettest September on record was 1981 with 199 mm. On average, September sees 112 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 Glasgow 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.
