September is one of the warmer months of the year in Lancaster, with average highs near 32.8°C and lows around 15.8°C (mean 24.3°C). It is one of the drier months, averaging 6 mm of rainfall and 37% relative humidity across the period.
September is one of the warmer months of the year in Lancaster. Across 45 years of records, the warmest September in Lancaster was 2020 — when the month averaged 27°C — while the coldest was 1986 at 19.3°C. Typical September days reach 32.8°C with nights near 15.8°C. The long-term trend is warming, about 0.4°C per decade.
September is one of the drier months in Lancaster, averaging 6 mm of rainfall. The wettest September on record was 1983 with 43 mm, while the driest were 2009, 2018 and 2020, among others at 0 mm.
Relative humidity in Lancaster during September averages 37%. The most humid September was 2023 at 59%, and the least humid was 2020 at 26%.
September receives about 6.1 kWh/m²/day of solar energy in Lancaster. The sunniest Septembers were 2003 and 2018 at 6.5 kWh/m²/day, and the cloudiest was 1984 at 5.4.
Average wind speed in Lancaster during September is 1.9 m/s. The windiest Septembers were 2016, 2017 and 2019, among others at 2.1 m/s, while the calmest were 2008, 2011 and 2020, among others at 1.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 23.2°C | 24.1°C | 24.5°C | 24.7°C | 25.4°C | +2.2°C |
| Avg High | 31.5°C | 32.6°C | 33.3°C | 33.2°C | 33.6°C | +2.1°C |
| Avg Low | 14.8°C | 15.7°C | 15.7°C | 16.1°C | 17.2°C | +2.4°C |
| Avg Rain | 15 mm | 4 mm | 3 mm | 4 mm | 5 mm | -10 mm |
September temperatures in Lancaster have risen by about 1.4°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 5.5°C (1986) to a record high of 44.8°C (2020).
Rainfall in September is one of the drier months, averaging 6 mm, with a wettest year of 43 mm.
One of the best times to visit Lancaster
September is one of the best times to visit Lancaster. Expect days averaging 32.8°C and nights around 15.8°C (mean 24.3°C) — warmer than Lancaster's yearly average — with low rainfall (6 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 | 32.2°C | 24.8°C | 17.4°C | 39.8°C | 13.4°C | 8 mm | 49% | 2 m/s | 5.8 |
| 2024 | 34.9°C | 26.2°C | 17.5°C | 43.3°C | 9.5°C | 1 mm | 35% | 1.8 m/s | 6.1 |
| 2023 | 29.9°C | 22.3°C | 14.8°C | 36.2°C | 10.7°C | 5 mm | 59% | 2 m/s | 5.6 |
| 2022 | 34.4°C | 26.6°C | 18.9°C | 43.5°C | 10.9°C | 14 mm | 42% | 1.9 m/s | 5.9 |
| 2021 | 33.9°C | 25.3°C | 16.7°C | 41.3°C | 9.4°C | 2 mm | 33% | 2 m/s | 6.2 |
| 2020 🔥 | 36.0°C | 27.0°C | 17.9°C | 44.8°C | 13.6°C | 0 mm | 26% | 1.7 m/s | 6.1 |
| 2019 | 32.0°C | 23.8°C | 15.6°C | 40.6°C | 6.0°C | 2 mm | 38% | 2.1 m/s | 6.2 |
| 2018 | 34.4°C | 25.2°C | 15.9°C | 39.6°C | 12.3°C | 0 mm | 32% | 1.9 m/s | 6.5 |
| 2017 | 31.2°C | 23.3°C | 15.3°C | 41.2°C | 7.1°C | 5 mm | 43% | 2.1 m/s | 6.1 |
| 2016 | 31.8°C | 23.3°C | 14.8°C | 37.6°C | 9.0°C | 0 mm | 37% | 2.1 m/s | 6.3 |
| 2015 | 32.9°C | 25.0°C | 17.1°C | 38.4°C | 10.7°C | 24 mm | 44% | 1.9 m/s | 6.1 |
| 2014 | 33.7°C | 25.5°C | 17.3°C | 39.9°C | 10.3°C | 2 mm | 37% | 1.8 m/s | 6.3 |
| 2013 | 32.7°C | 24.2°C | 15.7°C | 38.3°C | 7.3°C | 1 mm | 34% | 1.9 m/s | 6.4 |
| 2012 | 34.9°C | 26.5°C | 18.0°C | 38.4°C | 13.3°C | 2 mm | 29% | 1.8 m/s | 6.1 |
| 2011 | 34.3°C | 25.4°C | 16.6°C | 39.0°C | 11.4°C | 5 mm | 33% | 1.7 m/s | 6.1 |
| 2010 | 34.0°C | 24.5°C | 15.0°C | 40.2°C | 9.0°C | 2 mm | 30% | 1.8 m/s | 6.4 |
| 2009 | 34.8°C | 26.0°C | 17.2°C | 39.1°C | 7.1°C | 0 mm | 31% | 1.9 m/s | 6.3 |
| 2008 | 34.6°C | 25.7°C | 16.7°C | 39.7°C | 11.0°C | 0 mm | 33% | 1.7 m/s | 6.3 |
| 2007 | 30.6°C | 22.5°C | 14.3°C | 41.5°C | 8.1°C | 11 mm | 42% | 2.1 m/s | 6.3 |
| 2006 | 32.9°C | 24.1°C | 15.4°C | 39.2°C | 7.6°C | 3 mm | 29% | 2 m/s | 6.3 |
| 2005 | 30.5°C | 21.9°C | 13.3°C | 36.2°C | 8.9°C | 8 mm | 38% | 2 m/s | 6.3 |
| 2004 | 32.7°C | 23.9°C | 15.2°C | 40.1°C | 7.6°C | 0 mm | 33% | 1.9 m/s | 6.4 |
| 2003 | 35.9°C | 26.6°C | 17.3°C | 39.0°C | 13.0°C | 1 mm | 31% | 1.7 m/s | 6.5 |
| 2002 | 33.7°C | 25.0°C | 16.3°C | 40.5°C | 10.0°C | 1 mm | 31% | 1.9 m/s | 6.1 |
| 2001 | 34.4°C | 25.2°C | 16.0°C | 38.5°C | 12.5°C | 1 mm | 35% | 1.9 m/s | 6.4 |
| 2000 | 32.6°C | 23.8°C | 15.1°C | 40.3°C | 10.6°C | 3 mm | 37% | 2 m/s | 6.1 |
| 1999 | 33.1°C | 24.4°C | 15.6°C | 36.7°C | 11.0°C | 2 mm | 37% | 2 m/s | 6.3 |
| 1998 | 30.0°C | 22.4°C | 14.8°C | 37.3°C | 9.6°C | 14 mm | 51% | 2 m/s | 5.6 |
| 1997 | 33.2°C | 25.2°C | 17.2°C | 38.3°C | 12.3°C | 22 mm | 38% | 1.9 m/s | 6 |
| 1996 | 31.6°C | 23.0°C | 14.5°C | 36.3°C | 10.0°C | 0 mm | 39% | 2 m/s | 6.3 |
| 1995 | 34.1°C | 25.4°C | 16.7°C | 39.1°C | 8.1°C | 0 mm | 32% | 2 m/s | 6.3 |
| 1994 | 32.0°C | 23.6°C | 15.3°C | 37.3°C | 8.8°C | 2 mm | 35% | 1.9 m/s | 5.9 |
| 1993 | 32.8°C | 23.7°C | 14.6°C | 40.8°C | 7.7°C | 0 mm | 31% | 1.9 m/s | 6.3 |
| 1992 | 33.6°C | 24.9°C | 16.3°C | 37.1°C | 9.6°C | 0 mm | 30% | 1.8 m/s | 6.2 |
| 1991 | 33.2°C | 25.0°C | 16.7°C | 37.3°C | 8.4°C | 3 mm | 38% | 1.7 m/s | 6.1 |
| 1990 | 32.6°C | 23.8°C | 15.1°C | 40.1°C | 10.9°C | 1 mm | 35% | 1.9 m/s | 6.2 |
| 1989 | 32.1°C | 23.3°C | 14.4°C | 38.3°C | 8.4°C | 13 mm | 33% | 2.1 m/s | 6.1 |
| 1988 | 32.7°C | 24.0°C | 15.2°C | 41.1°C | 9.3°C | 2 mm | 34% | 2 m/s | 5.9 |
| 1987 | 32.9°C | 24.0°C | 15.2°C | 39.4°C | 10.4°C | 6 mm | 34% | 1.8 m/s | 5.8 |
| 1986 ❄️ | 27.6°C | 19.3°C | 10.9°C | 39.2°C | 5.5°C | 20 mm | 43% | 2.1 m/s | 5.8 |
| 1985 | 28.2°C | 20.3°C | 12.4°C | 35.5°C | 7.5°C | 8 mm | 46% | 2.1 m/s | 5.6 |
| 1984 | 34.0°C | 26.3°C | 18.5°C | 39.9°C | 11.7°C | 8 mm | 39% | 2 m/s | 5.4 |
| 1983 🌧️ | 32.6°C | 24.6°C | 16.7°C | 39.0°C | 9.8°C | 43 mm | 40% | 2 m/s | — |
| 1982 | 29.9°C | 22.3°C | 14.6°C | 40.6°C | 5.7°C | 22 mm | 42% | 2.1 m/s | — |
| 1981 | 33.1°C | 24.4°C | 15.7°C | 36.8°C | 10.1°C | 11 mm | 29% | 1.8 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 32.8°C with lows near 15.8°C (mean 24.3°C), based on 45 years of NASA POWER data.
September averages 6 mm of rainfall in Lancaster, one of the drier months. The wettest on record was 43 mm in 1983.
The hottest September reached 44.8°C in 2020. The coldest dipped to 5.5°C in 1986.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 1.4°C. Daytime highs moved from 31.6°C to 33.1°C and overnight lows from 15.6°C to 17.1°C over the same span.
September is one of the warmer months of the year in Lancaster and one of the drier months, so plan for around 32.8°C daytime highs and 15.8°C at night.
Not quite — September is the 10th coolest month in Lancaster, averaging 24.3°C.
For September in Lancaster, pack light, breathable clothing and sun protection, with typical highs of 32.8°C and lows of 15.8°C.
Relative humidity in September averages 37% — relatively dry.
Average wind speed in September is 1.9 m/s. The windiest September on record averaged 2.1 m/s (1982).
The wettest September on record was 1983 with 43 mm. On average, September sees 6 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 Lancaster 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.
