September is one of the warmer months of the year in Newport, with average highs near 17.8°C and lows around 11°C (mean 14.4°C). It is about average for rainfall, averaging 76 mm of rainfall and 85% relative humidity across the period.
September is one of the warmer months of the year in Newport. Across 45 years of records, the warmest September in Newport was 2023 — when the month averaged 17.1°C — while the coldest was 1986 at 11.7°C. Typical September days reach 17.8°C with nights near 11°C. The long-term trend is warming, about 0.2°C per decade.
September is about average for rainfall in Newport, averaging 76 mm of rainfall. The wettest September on record was 1981 with 155 mm, while the driest was 2014 at 17 mm.
Relative humidity in Newport during September averages 85%. The most humid September was 2000 at 88%, and the least humid were 1990 and 1991 at 80%.
September receives about 3.2 kWh/m²/day of solar energy in Newport. The sunniest Septembers were 1991 and 2015 at 3.6 kWh/m²/day, and the cloudiest was 2000 at 2.6.
Average wind speed in Newport during September is 3.6 m/s. The windiest September was 1983 at 4.5 m/s, while the calmest was 2014 at 2.5 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 14.1°C | 14.0°C | 14.7°C | 14.3°C | 15.3°C | +1.2°C |
| Avg High | 17.4°C | 17.4°C | 18.2°C | 17.7°C | 18.8°C | +1.4°C |
| Avg Low | 10.7°C | 10.6°C | 11.2°C | 10.9°C | 11.7°C | +1°C |
| Avg Rain | 81 mm | 84 mm | 60 mm | 76 mm | 83 mm | +2 mm |
September temperatures in Newport have risen by about 1°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 4.2°C (1986) to a record high of 26.6°C (2023).
Rainfall in September is about average for rainfall, averaging 76 mm, with a wettest year of 155 mm.
One of the best times to visit Newport
September is one of the best times to visit Newport. Expect days averaging 17.8°C and nights around 11°C (mean 14.4°C) — warmer than Newport's yearly average — with moderate rainfall (76 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 | 17.8°C | 14.4°C | 11.0°C | 21.2°C | 5.6°C | 101 mm | 84% | 4.1 m/s | 3.3 |
| 2024 | 17.6°C | 14.4°C | 11.2°C | 22.0°C | 5.9°C | 138 mm | 87% | 3.5 m/s | 2.7 |
| 2023 🔥 | 20.6°C | 17.1°C | 13.7°C | 26.6°C | 8.7°C | 77 mm | 85% | 3.3 m/s | 3.2 |
| 2022 | 18.6°C | 15.1°C | 11.6°C | 23.8°C | 7.3°C | 72 mm | 83% | 3.3 m/s | 3.1 |
| 2021 | 19.8°C | 16.1°C | 12.3°C | 26.2°C | 9.2°C | 68 mm | 85% | 3 m/s | 3.2 |
| 2020 | 18.3°C | 14.4°C | 10.6°C | 24.5°C | 5.8°C | 42 mm | 84% | 3.6 m/s | 3.5 |
| 2019 | 18.1°C | 14.7°C | 11.2°C | 22.9°C | 7.2°C | 128 mm | 85% | 4 m/s | 3.4 |
| 2018 | 17.6°C | 14.1°C | 10.7°C | 21.7°C | 5.7°C | 71 mm | 84% | 3.7 m/s | 3.1 |
| 2017 | 16.8°C | 13.8°C | 10.8°C | 20.0°C | 7.8°C | 97 mm | 87% | 3.9 m/s | 2.9 |
| 2016 | 18.9°C | 15.7°C | 12.5°C | 23.7°C | 9.0°C | 84 mm | 87% | 3.7 m/s | 3 |
| 2015 | 16.7°C | 12.9°C | 9.2°C | 20.0°C | 6.3°C | 59 mm | 85% | 3.3 m/s | 3.6 |
| 2014 | 19.4°C | 15.4°C | 11.4°C | 22.0°C | 8.4°C | 17 mm | 84% | 2.5 m/s | 3.4 |
| 2013 | 17.9°C | 14.2°C | 10.6°C | 22.2°C | 8.3°C | 69 mm | 85% | 3.2 m/s | 3 |
| 2012 | 16.1°C | 13.0°C | 9.9°C | 20.1°C | 6.1°C | 90 mm | 87% | 3.8 m/s | 3.4 |
| 2011 | 18.1°C | 15.1°C | 12.0°C | 23.2°C | 9.7°C | 71 mm | 86% | 4.4 m/s | 3.1 |
| 2010 | 17.5°C | 14.0°C | 10.6°C | 20.6°C | 5.3°C | 72 mm | 85% | 3.7 m/s | 3 |
| 2009 | 17.9°C | 14.1°C | 10.4°C | 21.7°C | 8.2°C | 31 mm | 85% | 3.6 m/s | 3.4 |
| 2008 | 16.9°C | 13.7°C | 10.5°C | 19.0°C | 7.4°C | 102 mm | 86% | 3.4 m/s | 3 |
| 2007 | 17.7°C | 14.2°C | 10.7°C | 21.6°C | 5.5°C | 43 mm | 86% | 3.6 m/s | 3.3 |
| 2006 | 20.1°C | 16.5°C | 13.0°C | 23.4°C | 8.8°C | 68 mm | 86% | 3.8 m/s | 3.2 |
| 2005 | 19.1°C | 15.3°C | 11.4°C | 24.8°C | 6.7°C | 57 mm | 85% | 3.4 m/s | 3.3 |
| 2004 | 18.3°C | 15.0°C | 11.8°C | 25.2°C | 9.0°C | 57 mm | 84% | 4.4 m/s | 3.3 |
| 2003 | 18.6°C | 14.7°C | 10.8°C | 22.7°C | 7.4°C | 24 mm | 81% | 2.7 m/s | 3.4 |
| 2002 | 18.4°C | 14.6°C | 10.8°C | 22.4°C | 7.6°C | 36 mm | 83% | 3 m/s | 3.4 |
| 2001 | 16.9°C | 13.8°C | 10.6°C | 20.4°C | 7.6°C | 50 mm | 85% | 3.9 m/s | 2.9 |
| 2000 | 18.1°C | 15.0°C | 12.0°C | 23.8°C | 8.3°C | 132 mm | 88% | 3.5 m/s | 2.6 |
| 1999 | 18.7°C | 15.3°C | 12.0°C | 24.0°C | 9.0°C | 126 mm | 86% | 3.5 m/s | 3.3 |
| 1998 | 18.1°C | 14.9°C | 11.7°C | 22.0°C | 8.0°C | 110 mm | 87% | 3.9 m/s | 3.1 |
| 1997 | 18.3°C | 14.5°C | 10.7°C | 22.0°C | 8.4°C | 38 mm | 85% | 3.4 m/s | 3.3 |
| 1996 | 17.8°C | 14.0°C | 10.1°C | 21.8°C | 7.2°C | 35 mm | 81% | 3.7 m/s | 3.3 |
| 1995 | 16.8°C | 13.8°C | 10.7°C | 20.7°C | 7.7°C | 109 mm | 84% | 3.6 m/s | 3 |
| 1994 | 16.0°C | 13.0°C | 10.0°C | 19.0°C | 6.3°C | 105 mm | 86% | 3.9 m/s | 3 |
| 1993 | 16.1°C | 12.8°C | 9.4°C | 22.0°C | 5.0°C | 102 mm | 84% | 3.4 m/s | 2.8 |
| 1992 | 16.2°C | 13.4°C | 10.5°C | 19.9°C | 7.4°C | 102 mm | 87% | 4 m/s | 3.1 |
| 1991 | 19.2°C | 15.4°C | 11.5°C | 24.6°C | 8.2°C | 60 mm | 80% | 3.5 m/s | 3.6 |
| 1990 | 17.2°C | 13.3°C | 9.5°C | 21.5°C | 4.9°C | 54 mm | 80% | 3.5 m/s | 3.3 |
| 1989 | 18.5°C | 15.1°C | 11.6°C | 23.0°C | 8.4°C | 64 mm | 83% | 3.5 m/s | 2.9 |
| 1988 | 16.7°C | 13.5°C | 10.4°C | 23.4°C | 6.4°C | 76 mm | 85% | 4 m/s | 2.9 |
| 1987 | 17.5°C | 14.2°C | 10.8°C | 21.8°C | 6.2°C | 67 mm | 85% | 3.5 m/s | 3 |
| 1986 ❄️ | 15.5°C | 11.7°C | 7.8°C | 18.4°C | 4.2°C | 27 mm | 83% | 2.9 m/s | 3.4 |
| 1985 | 18.0°C | 14.6°C | 11.2°C | 21.5°C | 7.2°C | 50 mm | 87% | 3.4 m/s | 3.2 |
| 1984 | 17.0°C | 14.0°C | 11.0°C | 22.8°C | 8.1°C | 111 mm | 81% | 4.1 m/s | 3.1 |
| 1983 | 17.2°C | 14.2°C | 11.2°C | 22.0°C | 7.8°C | 102 mm | 85% | 4.5 m/s | — |
| 1982 | 18.3°C | 14.8°C | 11.2°C | 25.0°C | 8.3°C | 80 mm | 86% | 3.1 m/s | — |
| 1981 🌧️ | 17.7°C | 14.6°C | 11.5°C | 21.2°C | 8.7°C | 155 mm | 84% | 3.7 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 17.8°C with lows near 11°C (mean 14.4°C), based on 45 years of NASA POWER data.
September averages 76 mm of rainfall in Newport, about average for rainfall. The wettest on record was 155 mm in 1981.
The hottest September reached 26.6°C in 2023. The coldest dipped to 4.2°C in 1986.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 1°C. Daytime highs moved from 17.6°C to 18.9°C and overnight lows from 11.2°C to 12°C over the same span.
September is one of the warmer months of the year in Newport and about average for rainfall, so plan for around 17.8°C daytime highs and 11°C at night.
Not quite — September is the 10th coolest month in Newport, averaging 14.4°C.
For September in Newport, pack light layers you can adjust through the day, with typical highs of 17.8°C and lows of 11°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 85% — quite humid.
Average wind speed in September is 3.6 m/s. The windiest September on record averaged 4.5 m/s (1983).
The wettest September on record was 1981 with 155 mm. On average, September sees 76 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 Newport 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.
