September is one of the warmer months of the year in Patan, with average highs near 37.8°C and lows around 21.8°C (mean 29.8°C). It is a relatively wet time of year, averaging 87 mm of rainfall and 69% relative humidity across the period.
September is one of the warmer months of the year in Patan. Across 45 years of records, the warmest September in Patan was 1999 — when the month averaged 33.7°C — while the coldest was 1994 at 25.7°C. Typical September days reach 37.8°C with nights near 21.8°C. The long-term trend is cooling, about 0.5°C per decade.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 30.8°C | 30.0°C | 30.2°C | 28.7°C | 28.8°C | -2°C |
| Avg High | 39.6°C | 38.2°C | 38.8°C | 36.2°C | 35.2°C | -4.4°C |
| Avg Low | 22.1°C | 21.8°C | 21.6°C | 21.3°C | 22.4°C | +0.3°C |
| Avg Rain | 38 mm | 85 mm | 54 mm | 127 mm | 155 mm | +118 mm |
September temperatures in Patan have fallen by about 1.3°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 18.6°C (1994) to a record high of 42.8°C (2001).
Rainfall in September is a relatively wet time of year, averaging 87 mm, with a wettest year of 286 mm.
Daytime highs and overnight lows have shifted differently — highs fell about 1°C per decade while lows rose 0°C per decade, narrowing the gap between day and night.
A good time to visit Patan
September is a good time to visit Patan, with days averaging 37.8°C and nights around 21.8°C (mean 29.8°C, warmer than Patan's yearly average) and higher rainfall. December and February are marginally more temperate, but September still suits most travellers.
| Year | High | Low | Avg | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|
| 2025 | 35.1°C | 22.1°C | 28.6°C | 122 mm | 83% | 2.4 m/s | 4.5 |
| 2024 | 34.8°C | 22.3°C | 28.6°C | 175 mm | 85% | 2.4 m/s | 4.5 |
| 2023 | 36.8°C | 21.9°C | 29.4°C | 208 mm | 77% | 2.5 m/s | 4.9 |
| 2022 | 33.7°C | 21.6°C | 27.7°C | 98 mm | 85% | 2.1 m/s | 5.2 |
| 2021 | 35.9°C | 24.5°C | 30.2°C | 221 mm | 80% | 2.2 m/s | 4.1 |
| 2020 | 34.8°C | 22.0°C | 28.4°C | 109 mm | 85% | 1.7 m/s | 5.1 |
| 2019 | 34.1°C | 23.9°C | 29.0°C | 227 mm | 86% | 1.7 m/s | 4 |
| 2018 | 40.1°C | 21.1°C | 30.6°C | 30 mm | 62% | 2.3 m/s | 5 |
| 2017 | 34.7°C | 20.7°C | 27.7°C | 40 mm | 79% | 1.7 m/s | 5.2 |
| 2016 | 36.9°C | 21.1°C | 29.0°C | 17 mm | 70% | 2.1 m/s | 5.5 |
| 2015 | 38.8°C | 20.0°C | 29.4°C | 64 mm | 64% | 2 m/s | 5.6 |
| 2014 | 35.2°C | 21.2°C | 28.2°C | 126 mm | 78% | 2 m/s | 4.8 |
| 2013 | 40.9°C | 23.0°C | 31.9°C | 194 mm | 68% | 2.2 m/s | 5 |
| 2012 | 35.1°C | 21.1°C | 28.1°C | 245 mm | 80% | 1.8 m/s | 4.7 |
| 2011 | 32.3°C | 20.5°C | 26.4°C | 168 mm | 86% | 2.2 m/s | 4.7 |
| 2010 | 33.5°C | 20.0°C | 26.8°C | 157 mm | 81% | 1.8 m/s | 5 |
| 2009 | 40.9°C | 21.4°C | 31.1°C | 9 mm | 69% | 2.4 m/s | 6.4 |
| 2008 | 38.4°C | 20.8°C | 29.6°C | 100 mm | 70% | 2 m/s | 5.4 |
| 2007 | 36.1°C | 20.8°C | 28.4°C | 65 mm | 79% | 1.8 m/s | 5.4 |
| 2006 | 33.3°C | 22.2°C | 27.8°C | 103 mm | 84% | 1.8 m/s | 5.3 |
| 2005 | 39.2°C | 21.3°C | 30.3°C | 180 mm | 72% | 2 m/s | 4.8 |
| 2004 | 39.1°C | 22.1°C | 30.6°C | 29 mm | 69% | 2 m/s | 5.8 |
| 2003 | 36.0°C | 21.9°C | 28.9°C | 13 mm | 79% | 2.2 m/s | 4.8 |
| 2002 | 40.9°C | 20.5°C | 30.7°C | 34 mm | 51% | 2.7 m/s | 6 |
| 2001 | 42.8°C | 23.6°C | 33.2°C | 7 mm | 48% | 2.1 m/s | 5.9 |
| 2000 | 41.7°C | 21.6°C | 31.7°C | 4 mm | 53% | 2.4 m/s | 5.6 |
| 1999 🔥 | 42.5°C | 24.9°C | 33.7°C | 24 mm | 45% | 2.8 m/s | 5.6 |
| 1998 | 39.2°C | 23.2°C | 31.2°C | 103 mm | 67% | 2.5 m/s | 5.2 |
| 1997 | 36.9°C | 21.4°C | 29.2°C | 70 mm | 72% | 2.1 m/s | 5.5 |
| 1996 | 38.3°C | 22.0°C | 30.1°C | 38 mm | 62% | 2.2 m/s | 5.3 |
| 1995 | 40.9°C | 22.5°C | 31.7°C | 34 mm | 51% | 2.3 m/s | 5.9 |
| 1994 ❄️ 🌧️ | 32.8°C | 18.6°C | 25.7°C | 286 mm | 79% | 1.9 m/s | 5.3 |
| 1993 | 40.0°C | 23.7°C | 31.9°C | 63 mm | 56% | 2.6 m/s | 5.8 |
| 1992 | 36.7°C | 18.8°C | 27.8°C | 124 mm | 69% | 2 m/s | 5.4 |
| 1991 | 39.5°C | 21.5°C | 30.5°C | 8 mm | 57% | 2.6 m/s | 5.6 |
| 1990 | 35.0°C | 21.6°C | 28.3°C | 100 mm | 79% | 2.1 m/s | 5.2 |
| 1989 | 38.2°C | 21.1°C | 29.7°C | 14 mm | 67% | 2 m/s | 5.8 |
| 1988 | 38.5°C | 23.7°C | 31.1°C | 74 mm | 72% | 2.2 m/s | 5.7 |
| 1987 | 42.6°C | 22.9°C | 32.7°C | 0 mm | 46% | 2.8 m/s | 6.3 |
| 1986 | 42.6°C | 23.0°C | 32.8°C | 0 mm | 41% | 2.3 m/s | 6.3 |
| 1985 | 40.2°C | 22.0°C | 31.1°C | 16 mm | 54% | 2.6 m/s | 6.1 |
| 1984 | 38.2°C | 20.4°C | 29.3°C | 75 mm | 65% | 2.4 m/s | 5.5 |
| 1983 | 39.4°C | 22.0°C | 30.7°C | 52 mm | 68% | 2 m/s | — |
| 1982 | 38.1°C | 20.9°C | 29.5°C | 3 mm | 63% | 2.1 m/s | — |
| 1981 | 38.2°C | 22.8°C | 30.5°C | 107 mm | 75% | 1.7 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 37.8°C with lows near 21.8°C (mean 29.8°C), based on 45 years of NASA POWER data.
September averages 87 mm of rainfall in Patan, a relatively wet time of year. The wettest on record was 286 mm in 1994.
The hottest September reached 42.8°C in 2001. The coldest dipped to 18.6°C in 1994.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have fallen by about 1.3°C. Daytime highs moved from 38.8°C to 35.3°C and overnight lows from 21.6°C to 22.5°C over the same span.
September is one of the warmer months of the year in Patan and a relatively wet time of year, so plan for around 37.8°C daytime highs and 21.8°C at night.
Not quite — September is the 7th coolest month in Patan, averaging 29.8°C.
For September in Patan, pack light, breathable clothing and sun protection, with typical highs of 37.8°C and lows of 21.8°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 69% — moderately humid.
Average wind speed in September is 2.2 m/s. The windiest September on record averaged 2.8 m/s (1987).
The wettest September on record was 1994 with 286 mm. On average, September sees 87 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 Patan 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.
