September is one of the warmer months of the year in Supaul, with average highs near 33.9°C and lows around 22.6°C (mean 28.3°C). It is a relatively wet time of year, averaging 187 mm of rainfall and 84% relative humidity across the period.
September is one of the warmer months of the year in Supaul. Across 45 years of records, the warmest September in Supaul was 1992 — when the month averaged 30°C — while the coldest was 1984 at 25.6°C. Typical September days reach 33.9°C with nights near 22.6°C. The long-term September temperature trend is broadly flat.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 27.9°C | 28.5°C | 28.1°C | 28.1°C | 28.7°C | +0.8°C |
| Avg High | 33.8°C | 34.9°C | 33.6°C | 33.7°C | 33.5°C | -0.3°C |
| Avg Low | 22.0°C | 22.2°C | 22.6°C | 22.6°C | 23.9°C | +1.9°C |
| Avg Rain | 171 mm | 119 mm | 175 mm | 204 mm | 318 mm | +147 mm |
September temperatures in Supaul have risen by about 1.1°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 19°C (1994) to a record high of 37.8°C (1992).
Rainfall in September is a relatively wet time of year, averaging 187 mm, with a wettest year of 588 mm.
Daytime highs and overnight lows have shifted differently — highs fell about 0.2°C per decade while lows rose 0.4°C per decade, narrowing the gap between day and night.
A good time to visit Supaul
September is a good time to visit Supaul, with days averaging 33.9°C and nights around 22.6°C (mean 28.3°C, warmer than Supaul's yearly average) and higher rainfall. November and February are marginally more temperate, but September still suits most travellers.
| Year | High | Low | Avg | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|
| 2025 | 33.2°C | 24.5°C | 28.9°C | 239 mm | 86% | 1.4 m/s | 4.5 |
| 2024 | 35.7°C | 23.5°C | 29.6°C | 358 mm | 88% | 2.1 m/s | 4.5 |
| 2023 | 33.5°C | 24.6°C | 29.0°C | 335 mm | 89% | 1.9 m/s | 4.4 |
| 2022 | 32.5°C | 23.5°C | 28.0°C | 257 mm | 88% | 1.8 m/s | 4.1 |
| 2021 | 32.9°C | 23.9°C | 28.4°C | 130 mm | 90% | 1.9 m/s | 4.7 |
| 2020 🌧️ | 33.3°C | 23.5°C | 28.4°C | 588 mm | 89% | 1.4 m/s | 3.6 |
| 2019 | 33.7°C | 21.7°C | 27.7°C | 370 mm | 89% | 2 m/s | 4 |
| 2018 | 33.5°C | 23.5°C | 28.5°C | 159 mm | 84% | 1.9 m/s | 4.7 |
| 2017 | 33.3°C | 24.8°C | 29.0°C | 139 mm | 88% | 1.8 m/s | 4.6 |
| 2016 | 32.5°C | 23.5°C | 28.0°C | 373 mm | 89% | 1.4 m/s | 3.9 |
| 2015 | 34.0°C | 21.0°C | 27.5°C | 199 mm | 85% | 1.6 m/s | 4.7 |
| 2014 | 33.7°C | 22.4°C | 28.1°C | 182 mm | 86% | 1.7 m/s | 4.6 |
| 2013 | 35.5°C | 22.9°C | 29.2°C | 96 mm | 81% | 1.8 m/s | 5.1 |
| 2012 | 35.1°C | 21.7°C | 28.4°C | 137 mm | 84% | 2.1 m/s | 4.6 |
| 2011 | 33.5°C | 22.2°C | 27.8°C | 202 mm | 89% | 2.5 m/s | 4.5 |
| 2010 | 32.4°C | 21.9°C | 27.2°C | 186 mm | 88% | 2 m/s | 4.6 |
| 2009 | 33.4°C | 23.5°C | 28.4°C | 112 mm | 86% | 1.9 m/s | 4.9 |
| 2008 | 32.4°C | 22.3°C | 27.3°C | 139 mm | 87% | 1.7 m/s | 4.9 |
| 2007 | 32.4°C | 21.8°C | 27.1°C | 258 mm | 87% | 2.1 m/s | 4.2 |
| 2006 | 34.8°C | 22.3°C | 28.5°C | 404 mm | 86% | 2.4 m/s | 4.4 |
| 2005 | 33.7°C | 23.6°C | 28.7°C | 107 mm | 86% | 1.7 m/s | 4.8 |
| 2004 | 32.8°C | 21.9°C | 27.4°C | 106 mm | 87% | 1.9 m/s | 4.6 |
| 2003 | 35.0°C | 23.4°C | 29.2°C | 123 mm | 81% | 2.5 m/s | 4.6 |
| 2002 | 34.7°C | 22.2°C | 28.4°C | 148 mm | 81% | 2.4 m/s | 4.8 |
| 2001 | 32.9°C | 23.2°C | 28.1°C | 185 mm | 85% | 1.7 m/s | 4.4 |
| 2000 | 33.7°C | 22.1°C | 27.9°C | 169 mm | 85% | 2.4 m/s | 4.3 |
| 1999 | 32.9°C | 22.1°C | 27.5°C | 85 mm | 85% | 2.7 m/s | 4.6 |
| 1998 | 34.3°C | 23.7°C | 29.0°C | 146 mm | 85% | 2 m/s | 4.8 |
| 1997 | 33.9°C | 21.4°C | 27.6°C | 84 mm | 82% | 1.8 m/s | 4.7 |
| 1996 | 35.6°C | 22.9°C | 29.2°C | 95 mm | 78% | 1.8 m/s | 5.1 |
| 1995 | 34.0°C | 22.1°C | 28.1°C | 97 mm | 83% | 2.8 m/s | 4.8 |
| 1994 | 36.8°C | 19.0°C | 27.9°C | 73 mm | 69% | 2.5 m/s | 5.2 |
| 1993 | 36.2°C | 22.7°C | 29.5°C | 189 mm | 80% | 2.5 m/s | 4.4 |
| 1992 🔥 | 37.8°C | 22.1°C | 30.0°C | 56 mm | 67% | 2.3 m/s | 4.6 |
| 1991 | 32.5°C | 23.1°C | 27.8°C | 253 mm | 87% | 2.1 m/s | 4.1 |
| 1990 | 35.2°C | 22.4°C | 28.8°C | 107 mm | 82% | 2.1 m/s | 4 |
| 1989 | 36.3°C | 23.4°C | 29.9°C | 151 mm | 78% | 2.3 m/s | 4 |
| 1988 | 33.7°C | 21.9°C | 27.8°C | 98 mm | 84% | 1.9 m/s | 4.5 |
| 1987 | 32.5°C | 22.1°C | 27.3°C | 312 mm | 88% | 1.8 m/s | 4.2 |
| 1986 | 33.8°C | 21.9°C | 27.8°C | 164 mm | 83% | 2.5 m/s | 4.6 |
| 1985 | 32.7°C | 23.0°C | 27.9°C | 224 mm | 87% | 1.8 m/s | 4.6 |
| 1984 ❄️ | 31.9°C | 19.4°C | 25.6°C | 220 mm | 87% | 1.8 m/s | 4.5 |
| 1983 | 35.4°C | 24.2°C | 29.8°C | 89 mm | 80% | 2.4 m/s | — |
| 1982 | 34.4°C | 20.1°C | 27.3°C | 149 mm | 81% | 1.8 m/s | — |
| 1981 | 33.4°C | 22.1°C | 27.8°C | 134 mm | 88% | 1.8 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 33.9°C with lows near 22.6°C (mean 28.3°C), based on 45 years of NASA POWER data.
September averages 187 mm of rainfall in Supaul, a relatively wet time of year. The wettest on record was 588 mm in 2020.
The hottest September reached 37.8°C in 1992. The coldest dipped to 19°C in 1994.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 1.1°C. Daytime highs moved from 33.6°C to 33.6°C and overnight lows from 21.8°C to 24°C over the same span.
September is one of the warmer months of the year in Supaul and a relatively wet time of year, so plan for around 33.9°C daytime highs and 22.6°C at night.
Not quite — September is the 7th coolest month in Supaul, averaging 28.3°C.
For September in Supaul, pack light, breathable clothing and sun protection, with typical highs of 33.9°C and lows of 22.6°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 84% — quite humid.
Average wind speed in September is 2 m/s. The windiest September on record averaged 2.8 m/s (1995).
The wettest September on record was 2020 with 588 mm. On average, September sees 187 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 Supaul 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.
