September is one of the warmer months of the year in Barnstaple, with average highs near 17.4°C and lows around 10.9°C (mean 14.2°C). It is about average for rainfall, averaging 81 mm of rainfall and 86% relative humidity across the period.
September is one of the warmer months of the year in Barnstaple. Across 45 years of records, the warmest September in Barnstaple was 2023 — when the month averaged 16.8°C — while the coldest was 1986 at 11.5°C. Typical September days reach 17.4°C with nights near 10.9°C. The long-term trend is warming, about 0.2°C per decade.
September is about average for rainfall in Barnstaple, averaging 81 mm of rainfall. The wettest September on record was 2024 with 160 mm, while the driest was 2014 at 18 mm.
Relative humidity in Barnstaple during September averages 86%. The most humid September was 1998 at 89%, and the least humid was 1990 at 81%.
September receives about 3.3 kWh/m²/day of solar energy in Barnstaple. The sunniest September was 2014 at 3.9 kWh/m²/day, and the cloudiest was 2000 at 2.7.
Average wind speed in Barnstaple during September is 3.6 m/s. The windiest September was 1983 at 4.6 m/s, while the calmest was 2014 at 2.4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 13.8°C | 13.8°C | 14.4°C | 14.1°C | 14.9°C | +1.1°C |
| Avg High | 17.1°C | 17.1°C | 17.6°C | 17.3°C | 18.3°C | +1.2°C |
| Avg Low | 10.6°C | 10.6°C | 11.1°C | 10.9°C | 11.6°C | +1°C |
| Avg Rain | 81 mm | 90 mm | 63 mm | 83 mm | 95 mm | +14 mm |
September temperatures in Barnstaple have risen by about 0.9°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 4.3°C (1986) to a record high of 26.4°C (2023).
Rainfall in September is about average for rainfall, averaging 81 mm, with a wettest year of 160 mm.
One of the best times to visit Barnstaple
September is one of the best times to visit Barnstaple. Expect days averaging 17.4°C and nights around 10.9°C (mean 14.2°C) — warmer than Barnstaple's yearly average — with higher rainfall (81 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 | 17.3°C | 14.0°C | 10.8°C | 20.3°C | 5.4°C | 109 mm | 86% | 4.1 m/s | 3.4 |
| 2024 🌧️ | 17.1°C | 14.1°C | 11.0°C | 22.8°C | 6.3°C | 160 mm | 88% | 3.5 m/s | 2.8 |
| 2023 🔥 | 20.2°C | 16.8°C | 13.4°C | 26.4°C | 9.1°C | 86 mm | 87% | 3.3 m/s | 3.2 |
| 2022 | 17.9°C | 14.8°C | 11.7°C | 22.3°C | 7.4°C | 87 mm | 85% | 3.5 m/s | 3.1 |
| 2021 | 19.3°C | 15.7°C | 12.1°C | 24.7°C | 8.9°C | 75 mm | 87% | 2.9 m/s | 3.1 |
| 2020 | 17.8°C | 14.3°C | 10.7°C | 23.1°C | 7.2°C | 50 mm | 85% | 3.5 m/s | 3.4 |
| 2019 | 17.6°C | 14.5°C | 11.4°C | 20.8°C | 7.4°C | 136 mm | 86% | 4.1 m/s | 3.4 |
| 2018 | 17.4°C | 14.0°C | 10.7°C | 21.8°C | 5.2°C | 73 mm | 85% | 3.7 m/s | 3.3 |
| 2017 | 16.3°C | 13.6°C | 10.9°C | 19.7°C | 7.9°C | 124 mm | 88% | 4.1 m/s | 3.2 |
| 2016 | 18.3°C | 15.3°C | 12.2°C | 22.5°C | 8.0°C | 91 mm | 89% | 3.7 m/s | 3.1 |
| 2015 | 16.1°C | 12.7°C | 9.3°C | 19.4°C | 6.5°C | 74 mm | 87% | 3.5 m/s | 3.7 |
| 2014 | 19.1°C | 15.3°C | 11.4°C | 22.1°C | 8.5°C | 18 mm | 86% | 2.4 m/s | 3.9 |
| 2013 | 17.6°C | 14.3°C | 10.9°C | 21.7°C | 8.5°C | 67 mm | 86% | 3.3 m/s | 3 |
| 2012 | 15.9°C | 13.0°C | 10.1°C | 20.0°C | 6.1°C | 88 mm | 87% | 3.7 m/s | 3.3 |
| 2011 | 17.7°C | 14.8°C | 12.0°C | 22.5°C | 9.1°C | 73 mm | 87% | 4.5 m/s | 3.1 |
| 2010 | 16.9°C | 13.7°C | 10.4°C | 20.2°C | 4.8°C | 84 mm | 87% | 3.7 m/s | 3.2 |
| 2009 | 17.3°C | 13.8°C | 10.3°C | 21.6°C | 8.1°C | 38 mm | 87% | 3.5 m/s | 3.4 |
| 2008 | 16.5°C | 13.4°C | 10.3°C | 18.4°C | 7.7°C | 104 mm | 87% | 3.5 m/s | 3.3 |
| 2007 | 17.3°C | 14.0°C | 10.6°C | 21.4°C | 5.7°C | 46 mm | 87% | 3.5 m/s | 3.6 |
| 2006 | 19.5°C | 16.2°C | 12.9°C | 22.6°C | 9.5°C | 57 mm | 87% | 3.9 m/s | 3.4 |
| 2005 | 18.3°C | 14.9°C | 11.4°C | 22.5°C | 6.7°C | 72 mm | 87% | 3.4 m/s | 3.4 |
| 2004 | 17.7°C | 14.7°C | 11.7°C | 24.1°C | 8.5°C | 61 mm | 86% | 4.5 m/s | 3.3 |
| 2003 | 17.9°C | 14.2°C | 10.4°C | 22.1°C | 5.4°C | 32 mm | 85% | 2.8 m/s | 3.5 |
| 2002 | 17.8°C | 14.1°C | 10.4°C | 21.5°C | 7.3°C | 44 mm | 85% | 2.9 m/s | 3.6 |
| 2001 | 16.4°C | 13.6°C | 10.8°C | 19.2°C | 8.1°C | 48 mm | 86% | 4 m/s | 3.3 |
| 2000 | 17.7°C | 14.8°C | 11.8°C | 22.9°C | 8.9°C | 131 mm | 89% | 3.6 m/s | 2.7 |
| 1999 | 18.2°C | 15.0°C | 11.7°C | 22.9°C | 7.9°C | 121 mm | 88% | 3.5 m/s | 3.3 |
| 1998 | 17.4°C | 14.6°C | 11.7°C | 21.0°C | 8.5°C | 116 mm | 89% | 4.1 m/s | 3.2 |
| 1997 | 18.2°C | 14.4°C | 10.6°C | 21.9°C | 8.7°C | 29 mm | 87% | 3.4 m/s | 3.2 |
| 1996 | 17.3°C | 13.6°C | 9.9°C | 20.6°C | 6.6°C | 38 mm | 84% | 3.6 m/s | 3.7 |
| 1995 | 16.5°C | 13.5°C | 10.6°C | 20.5°C | 8.1°C | 110 mm | 86% | 3.7 m/s | 3.5 |
| 1994 | 15.7°C | 12.9°C | 10.1°C | 19.3°C | 7.4°C | 128 mm | 88% | 3.8 m/s | 3 |
| 1993 | 15.7°C | 12.6°C | 9.6°C | 21.1°C | 6.8°C | 121 mm | 86% | 3.5 m/s | 3.3 |
| 1992 | 16.0°C | 13.2°C | 10.4°C | 19.6°C | 8.4°C | 91 mm | 87% | 4 m/s | 3.1 |
| 1991 | 18.8°C | 15.1°C | 11.4°C | 23.7°C | 8.0°C | 84 mm | 83% | 3.3 m/s | 3.6 |
| 1990 | 17.0°C | 13.4°C | 9.7°C | 22.3°C | 6.1°C | 58 mm | 81% | 3.4 m/s | 3.5 |
| 1989 | 18.1°C | 14.8°C | 11.4°C | 22.2°C | 8.3°C | 75 mm | 85% | 3.4 m/s | 3 |
| 1988 | 16.4°C | 13.4°C | 10.3°C | 22.3°C | 6.3°C | 72 mm | 87% | 4 m/s | 3.2 |
| 1987 | 17.3°C | 14.0°C | 10.7°C | 21.9°C | 4.9°C | 69 mm | 86% | 3.4 m/s | 3.4 |
| 1986 ❄️ | 15.3°C | 11.5°C | 7.8°C | 17.9°C | 4.3°C | 29 mm | 85% | 2.8 m/s | 3.4 |
| 1985 | 17.7°C | 14.4°C | 11.0°C | 21.1°C | 7.4°C | 50 mm | 88% | 3.5 m/s | 3.2 |
| 1984 | 16.5°C | 13.6°C | 10.8°C | 22.7°C | 8.1°C | 105 mm | 82% | 4.2 m/s | 3.3 |
| 1983 | 16.9°C | 14.0°C | 11.0°C | 22.2°C | 8.2°C | 98 mm | 86% | 4.6 m/s | — |
| 1982 | 18.1°C | 14.6°C | 11.1°C | 24.5°C | 6.7°C | 83 mm | 88% | 3.2 m/s | — |
| 1981 | 17.4°C | 14.3°C | 11.1°C | 21.2°C | 8.3°C | 147 mm | 86% | 3.6 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 17.4°C with lows near 10.9°C (mean 14.2°C), based on 45 years of NASA POWER data.
September averages 81 mm of rainfall in Barnstaple, about average for rainfall. The wettest on record was 160 mm in 2024.
The hottest September reached 26.4°C in 2023. The coldest dipped to 4.3°C in 1986.
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 17.3°C to 18.4°C and overnight lows from 11°C to 11.8°C over the same span.
September is one of the warmer months of the year in Barnstaple and about average for rainfall, so plan for around 17.4°C daytime highs and 10.9°C at night.
Not quite — September is the 10th coolest month in Barnstaple, averaging 14.2°C.
For September in Barnstaple, pack light layers you can adjust through the day, with typical highs of 17.4°C and lows of 10.9°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 86% — quite humid.
Average wind speed in September is 3.6 m/s. The windiest September on record averaged 4.6 m/s (1983).
The wettest September on record was 2024 with 160 mm. On average, September sees 81 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 Barnstaple 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.
