September is one of the warmer months of the year in Lake Country, with average highs near 19.2°C and lows around 5.3°C (mean 12.3°C). It is about average for rainfall, averaging 30 mm of rainfall and 63% relative humidity across the period.
September is one of the warmer months of the year in Lake Country. Across 45 years of records, the warmest September in Lake Country was 2025 — when the month averaged 16.1°C — while the coldest was 1985 at 8.5°C. Typical September days reach 19.2°C with nights near 5.3°C. The long-term trend is warming, about 0.5°C per decade.
September is about average for rainfall in Lake Country, averaging 30 mm of rainfall. The wettest September on record was 2019 with 80 mm, while the driest was 1991 at 4 mm.
Relative humidity in Lake Country during September averages 63%. The most humid September was 2019 at 74%, and the least humid was 1987 at 52%.
September receives about 3.8 kWh/m²/day of solar energy in Lake Country. The sunniest Septembers were 1990 and 1995 at 4.6 kWh/m²/day, and the cloudiest were 2010 and 2019 at 3.1.
Average wind speed in Lake Country during September is 0.4 m/s. The windiest Septembers were 2008 and 2012 at 0.5 m/s, while the calmest were 2023, 2024 and 2025, among others at 0.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 10.9°C | 12.9°C | 11.9°C | 12.2°C | 14.1°C | +3.2°C |
| Avg High | 17.8°C | 20.2°C | 19.0°C | 18.8°C | 21.0°C | +3.2°C |
| Avg Low | 4.1°C | 5.5°C | 4.9°C | 5.6°C | 7.3°C | +3.2°C |
| Avg Rain | 36 mm | 22 mm | 28 mm | 40 mm | 24 mm | -12 mm |
September temperatures in Lake Country have risen by about 4°C between 1981–1985 and 2021–2025.
September has ranged from a record low of -5.4°C (1983) to a record high of 34.7°C (1988).
Rainfall in September is about average for rainfall, averaging 30 mm, with a wettest year of 80 mm.
One of the best times to visit Lake Country
September is one of the best times to visit Lake Country. Expect days averaging 19.2°C and nights around 5.3°C (mean 12.3°C) — warmer than Lake Country's yearly average — with moderate rainfall (30 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 🔥 | 23.0°C | 16.1°C | 9.2°C | 32.9°C | 3.8°C | 30 mm | 68% | 0.3 m/s | 4 |
| 2024 | 20.8°C | 14.1°C | 7.5°C | 32.9°C | -0.5°C | 29 mm | 65% | 0.3 m/s | 3.7 |
| 2023 | 19.4°C | 12.7°C | 6.0°C | 27.6°C | 0.6°C | 29 mm | 65% | 0.3 m/s | 3.7 |
| 2022 | 22.3°C | 14.9°C | 7.6°C | 32.3°C | 3.0°C | 9 mm | 60% | 0.4 m/s | 4 |
| 2021 | 18.7°C | 12.2°C | 5.7°C | 28.0°C | -1.3°C | 32 mm | 66% | 0.3 m/s | 3.3 |
| 2020 | 21.6°C | 14.7°C | 7.9°C | 29.4°C | 1.5°C | 16 mm | 65% | 0.4 m/s | 3.8 |
| 2019 🌧️ | 16.6°C | 11.1°C | 5.7°C | 28.5°C | -2.9°C | 80 mm | 74% | 0.3 m/s | 3.1 |
| 2018 | 16.3°C | 10.3°C | 4.3°C | 25.7°C | 1.1°C | 51 mm | 70% | 0.4 m/s | 3.4 |
| 2017 | 20.0°C | 13.2°C | 6.5°C | 30.3°C | 0.5°C | 16 mm | 63% | 0.4 m/s | 3.6 |
| 2016 | 17.0°C | 10.7°C | 4.5°C | 24.6°C | 1.1°C | 43 mm | 71% | 0.4 m/s | 3.5 |
| 2015 | 17.2°C | 10.7°C | 4.3°C | 28.9°C | -0.8°C | 38 mm | 65% | 0.4 m/s | 3.5 |
| 2014 | 19.8°C | 13.0°C | 6.2°C | 27.2°C | -0.3°C | 37 mm | 64% | 0.4 m/s | 3.9 |
| 2013 | 19.7°C | 13.4°C | 7.0°C | 30.5°C | -1.9°C | 61 mm | 69% | 0.4 m/s | 3.6 |
| 2012 | 22.2°C | 14.3°C | 6.4°C | 27.5°C | 0.8°C | 7 mm | 53% | 0.5 m/s | 4.4 |
| 2011 | 22.2°C | 14.5°C | 6.8°C | 30.5°C | 1.5°C | 10 mm | 55% | 0.4 m/s | 4.1 |
| 2010 | 17.0°C | 10.7°C | 4.5°C | 25.9°C | -0.2°C | 55 mm | 72% | 0.3 m/s | 3.1 |
| 2009 | 21.6°C | 14.0°C | 6.4°C | 29.8°C | -0.1°C | 26 mm | 58% | 0.3 m/s | 4.2 |
| 2008 | 19.8°C | 12.3°C | 4.8°C | 28.1°C | 0.1°C | 29 mm | 57% | 0.5 m/s | 4 |
| 2007 | 17.4°C | 10.9°C | 4.3°C | 27.8°C | -1.3°C | 37 mm | 66% | 0.3 m/s | 3.6 |
| 2006 | 20.9°C | 13.4°C | 5.9°C | 32.0°C | -1.3°C | 23 mm | 61% | 0.4 m/s | 3.9 |
| 2005 | 16.8°C | 10.2°C | 3.5°C | 24.1°C | -2.0°C | 25 mm | 68% | 0.4 m/s | 3.5 |
| 2004 | 16.5°C | 10.4°C | 4.3°C | 23.6°C | -1.7°C | 45 mm | 72% | 0.3 m/s | 3.2 |
| 2003 | 20.4°C | 13.0°C | 5.6°C | 32.1°C | -0.5°C | 21 mm | 56% | 0.4 m/s | 3.7 |
| 2002 | 18.7°C | 11.5°C | 4.3°C | 27.3°C | -0.3°C | 20 mm | 62% | 0.4 m/s | 3.7 |
| 2001 | 20.7°C | 13.1°C | 5.5°C | 28.7°C | 1.3°C | 18 mm | 56% | 0.4 m/s | 4.2 |
| 2000 | 17.3°C | 10.6°C | 3.9°C | 27.3°C | -4.1°C | 38 mm | 65% | 0.4 m/s | 3.6 |
| 1999 | 18.8°C | 11.5°C | 4.2°C | 26.9°C | -1.9°C | 15 mm | 57% | 0.4 m/s | 4 |
| 1998 | 22.9°C | 15.2°C | 7.5°C | 29.8°C | 1.5°C | 15 mm | 57% | 0.4 m/s | 4.2 |
| 1997 | 19.7°C | 13.0°C | 6.2°C | 26.7°C | 0.5°C | 52 mm | 65% | 0.4 m/s | 3.6 |
| 1996 | 17.0°C | 10.2°C | 3.4°C | 29.5°C | -1.7°C | 43 mm | 67% | 0.4 m/s | 3.3 |
| 1995 | 21.9°C | 14.3°C | 6.7°C | 29.7°C | 0.5°C | 17 mm | 54% | 0.4 m/s | 4.6 |
| 1994 | 22.0°C | 14.3°C | 6.7°C | 28.4°C | 2.6°C | 22 mm | 58% | 0.4 m/s | 4.1 |
| 1993 | 20.0°C | 12.6°C | 5.3°C | 27.5°C | -1.1°C | 22 mm | 57% | 0.4 m/s | 4.5 |
| 1992 | 16.8°C | 9.8°C | 2.7°C | 25.7°C | -3.9°C | 22 mm | 64% | 0.3 m/s | 3.3 |
| 1991 | 20.6°C | 13.2°C | 5.8°C | 27.0°C | -0.4°C | 4 mm | 59% | 0.4 m/s | 4.4 |
| 1990 | 22.6°C | 14.4°C | 6.2°C | 27.6°C | 2.9°C | 6 mm | 57% | 0.4 m/s | 4.6 |
| 1989 | 19.8°C | 12.4°C | 5.0°C | 25.7°C | -0.6°C | 30 mm | 62% | 0.4 m/s | 4.3 |
| 1988 | 19.3°C | 12.0°C | 4.8°C | 34.7°C | -1.9°C | 31 mm | 62% | 0.3 m/s | 3.5 |
| 1987 | 22.7°C | 14.6°C | 6.5°C | 30.2°C | -0.2°C | 11 mm | 52% | 0.4 m/s | 4.4 |
| 1986 | 15.4°C | 9.3°C | 3.1°C | 23.8°C | -2.1°C | 58 mm | 69% | 0.3 m/s | 3.6 |
| 1985 ❄️ | 14.6°C | 8.5°C | 2.3°C | 20.7°C | -3.8°C | 63 mm | 67% | 0.4 m/s | 3.6 |
| 1984 | 15.9°C | 9.3°C | 2.8°C | 23.8°C | -3.5°C | 24 mm | 64% | 0.4 m/s | 3.4 |
| 1983 | 15.4°C | 8.8°C | 2.3°C | 20.9°C | -5.4°C | 34 mm | 67% | 0.4 m/s | — |
| 1982 | 18.1°C | 11.7°C | 5.4°C | 27.7°C | 0.6°C | 43 mm | 69% | 0.4 m/s | — |
| 1981 | 18.7°C | 11.8°C | 4.8°C | 30.9°C | -2.3°C | 28 mm | 65% | 0.4 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 19.2°C with lows near 5.3°C (mean 12.3°C), based on 45 years of NASA POWER data.
September averages 30 mm of rainfall in Lake Country, about average for rainfall. The wettest on record was 80 mm in 2019.
The hottest September reached 34.7°C in 1988. The coldest dipped to -5.4°C in 1983.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 4°C. Daytime highs moved from 16.5°C to 20.8°C and overnight lows from 3.5°C to 7.2°C over the same span.
September is one of the warmer months of the year in Lake Country and about average for rainfall, so plan for around 19.2°C daytime highs and 5.3°C at night.
Not quite — September is the 9th coolest month in Lake Country, averaging 12.3°C.
For September in Lake Country, pack warm layers and a jacket for chilly mornings, with typical highs of 19.2°C and lows of 5.3°C.
Relative humidity in September averages 63% — moderately humid.
Average wind speed in September is 0.4 m/s. The windiest September on record averaged 0.5 m/s (2008).
The wettest September on record was 2019 with 80 mm. On average, September sees 30 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 Lake Country 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.
