September is one of the cooler months of the year in Mackay, with average highs near 23.6°C and lows around 20.8°C (mean 22.2°C). It is one of the drier months, averaging 19 mm of rainfall and 73% relative humidity across the period.
September is one of the cooler months of the year in Mackay. Across 45 years of records, the warmest September in Mackay was 2010 — when the month averaged 23.5°C — while the coldest was 1990 at 20.5°C. Typical September days reach 23.6°C with nights near 20.8°C. The long-term September temperature trend is broadly flat.
September is one of the drier months in Mackay, averaging 19 mm of rainfall. The wettest September on record was 2010 with 154 mm, while the driest were 1991 and 2019 at 0 mm.
Relative humidity in Mackay during September averages 73%. The most humid September was 2010 at 83%, and the least humid was 1991 at 65%.
September receives about 6 kWh/m²/day of solar energy in Mackay. The sunniest Septembers were 2003, 2017 and 2019, among others at 6.4 kWh/m²/day, and the cloudiest was 2010 at 4.6.
Average wind speed in Mackay during September is 3.8 m/s. The windiest September was 1981 at 4.9 m/s, while the calmest was 1984 at 3.2 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 21.9°C | 22.1°C | 22.2°C | 22.3°C | 22.5°C | +0.6°C |
| Avg High | 23.5°C | 23.5°C | 23.7°C | 23.7°C | 23.7°C | +0.2°C |
| Avg Low | 20.4°C | 20.6°C | 20.8°C | 21.0°C | 21.2°C | +0.8°C |
| Avg Rain | 15 mm | 24 mm | 15 mm | 27 mm | 11 mm | -4 mm |
September temperatures in Mackay have risen by about 0.5°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 15.3°C (1985) to a record high of 28.1°C (2010).
Rainfall in September is one of the drier months, averaging 19 mm, with a wettest year of 154 mm.
One of the best times to visit Mackay
September is one of the best times to visit Mackay. Expect days averaging 23.6°C and nights around 20.8°C (mean 22.2°C) — cooler than Mackay's yearly average — with low rainfall (19 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 | 23.9°C | 22.6°C | 21.3°C | 26.2°C | 19.3°C | 13 mm | 76% | 4 m/s | 5.9 |
| 2024 | 24.3°C | 23.0°C | 21.6°C | 28.0°C | 20.4°C | 9 mm | 73% | 4.1 m/s | 5.9 |
| 2023 | 23.8°C | 22.6°C | 21.4°C | 25.9°C | 20.6°C | 8 mm | 74% | 4.5 m/s | 6.3 |
| 2022 | 23.9°C | 22.4°C | 20.9°C | 26.3°C | 16.4°C | 25 mm | 79% | 3.3 m/s | 5.7 |
| 2021 | 23.1°C | 21.8°C | 20.5°C | 26.3°C | 16.0°C | 4 mm | 71% | 4.4 m/s | 6 |
| 2020 | 23.4°C | 22.3°C | 21.2°C | 26.6°C | 19.5°C | 9 mm | 76% | 4.6 m/s | 5.9 |
| 2019 | 23.4°C | 21.7°C | 20.1°C | 25.7°C | 17.2°C | 0 mm | 70% | 3.4 m/s | 6.4 |
| 2018 | 23.7°C | 22.3°C | 20.9°C | 26.7°C | 19.6°C | 8 mm | 73% | 3.9 m/s | 6.1 |
| 2017 | 24.1°C | 22.6°C | 21.1°C | 26.9°C | 19.9°C | 1 mm | 72% | 3.5 m/s | 6.4 |
| 2016 | 24.5°C | 23.2°C | 21.9°C | 27.4°C | 19.5°C | 41 mm | 78% | 3.6 m/s | 5.4 |
| 2015 | 23.6°C | 22.3°C | 21.0°C | 26.6°C | 19.5°C | 11 mm | 71% | 4.1 m/s | 6.1 |
| 2014 | 22.9°C | 21.6°C | 20.3°C | 25.2°C | 17.6°C | 38 mm | 75% | 3.5 m/s | 6 |
| 2013 | 24.7°C | 23.2°C | 21.7°C | 27.8°C | 20.0°C | 6 mm | 75% | 4.1 m/s | 6.2 |
| 2012 | 23.1°C | 21.8°C | 20.5°C | 25.5°C | 18.5°C | 4 mm | 73% | 3.6 m/s | 6 |
| 2011 | 22.4°C | 21.0°C | 19.6°C | 26.0°C | 16.5°C | 5 mm | 73% | 4.1 m/s | 6.2 |
| 2010 🔥 🌧️ | 24.6°C | 23.5°C | 22.4°C | 28.1°C | 20.6°C | 154 mm | 83% | 3.6 m/s | 4.6 |
| 2009 | 24.7°C | 23.3°C | 21.9°C | 27.7°C | 20.4°C | 4 mm | 69% | 3.7 m/s | 5.9 |
| 2008 | 23.2°C | 21.9°C | 20.5°C | 24.7°C | 18.1°C | 15 mm | 77% | 3.5 m/s | 5.9 |
| 2007 | 23.0°C | 21.6°C | 20.2°C | 25.5°C | 18.5°C | 44 mm | 77% | 3.5 m/s | 6 |
| 2006 | 22.9°C | 21.4°C | 20.0°C | 26.1°C | 15.6°C | 34 mm | 75% | 4.5 m/s | 6 |
| 2005 | 23.6°C | 22.2°C | 20.8°C | 26.1°C | 19.2°C | 2 mm | 72% | 3.4 m/s | 6.3 |
| 2004 | 23.2°C | 21.9°C | 20.6°C | 24.7°C | 17.5°C | 5 mm | 70% | 3.8 m/s | 6.2 |
| 2003 | 24.4°C | 22.8°C | 21.1°C | 28.0°C | 18.1°C | 1 mm | 69% | 3.5 m/s | 6.4 |
| 2002 | 24.0°C | 22.4°C | 20.8°C | 26.3°C | 18.9°C | 14 mm | 73% | 3.6 m/s | 6.4 |
| 2001 | 24.0°C | 22.7°C | 21.3°C | 26.3°C | 19.4°C | 26 mm | 73% | 4.3 m/s | 5.9 |
| 2000 | 23.6°C | 22.1°C | 20.6°C | 26.3°C | 19.1°C | 1 mm | 72% | 3.8 m/s | 6.3 |
| 1999 | 22.8°C | 21.5°C | 20.3°C | 25.9°C | 18.8°C | 35 mm | 77% | 4.5 m/s | 5.9 |
| 1998 | 23.6°C | 22.7°C | 21.7°C | 25.3°C | 19.4°C | 61 mm | 81% | 4 m/s | 5.3 |
| 1997 | 24.1°C | 22.5°C | 21.0°C | 26.8°C | 19.0°C | 25 mm | 76% | 3.9 m/s | 6 |
| 1996 | 23.8°C | 22.0°C | 20.1°C | 26.9°C | 16.2°C | 32 mm | 67% | 3.6 m/s | 6.4 |
| 1995 | 23.2°C | 21.9°C | 20.5°C | 26.5°C | 16.6°C | 8 mm | 73% | 3.7 m/s | 6.1 |
| 1994 | 23.0°C | 21.4°C | 19.9°C | 27.0°C | 18.6°C | 5 mm | 71% | 3.7 m/s | 6.2 |
| 1993 | 23.5°C | 22.1°C | 20.8°C | 26.9°C | 19.2°C | 35 mm | 75% | 4.3 m/s | 5.5 |
| 1992 | 24.8°C | 23.3°C | 21.7°C | 27.6°C | 19.2°C | 23 mm | 74% | 3.5 m/s | 5.6 |
| 1991 | 24.4°C | 22.7°C | 20.9°C | 26.7°C | 18.5°C | 0 mm | 65% | 3.5 m/s | 6.4 |
| 1990 ❄️ | 22.0°C | 20.5°C | 19.1°C | 23.8°C | 15.9°C | 11 mm | 71% | 4.3 m/s | 5.8 |
| 1989 | 23.3°C | 21.6°C | 20.0°C | 26.6°C | 16.9°C | 1 mm | 74% | 3.7 m/s | 6 |
| 1988 | 23.5°C | 21.9°C | 20.2°C | 26.5°C | 17.2°C | 9 mm | 76% | 3.7 m/s | 6 |
| 1987 | 23.0°C | 21.7°C | 20.4°C | 24.8°C | 17.5°C | 8 mm | 73% | 4.1 m/s | 5.6 |
| 1986 | 23.9°C | 22.3°C | 20.8°C | 28.0°C | 19.0°C | 32 mm | 73% | 3.8 m/s | 5.8 |
| 1985 | 23.4°C | 21.6°C | 19.7°C | 27.1°C | 15.3°C | 8 mm | 71% | 3.9 m/s | 6.2 |
| 1984 | 24.2°C | 22.5°C | 20.8°C | 26.6°C | 18.4°C | 27 mm | 69% | 3.2 m/s | 6 |
| 1983 | 24.1°C | 22.7°C | 21.4°C | 26.6°C | 19.4°C | 23 mm | 79% | 3.5 m/s | — |
| 1982 | 22.5°C | 21.0°C | 19.4°C | 27.2°C | 17.7°C | 17 mm | 75% | 3.5 m/s | — |
| 1981 | 23.3°C | 22.1°C | 20.9°C | 26.3°C | 17.5°C | 12 mm | 72% | 4.9 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 23.6°C with lows near 20.8°C (mean 22.2°C), based on 45 years of NASA POWER data.
September averages 19 mm of rainfall in Mackay, one of the drier months. The wettest on record was 154 mm in 2010.
The hottest September reached 28.1°C in 2010. The coldest dipped to 15.3°C in 1985.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 0.5°C. Daytime highs moved from 23.5°C to 23.8°C and overnight lows from 20.4°C to 21.1°C over the same span.
September is one of the cooler months of the year in Mackay and one of the drier months, so plan for around 23.6°C daytime highs and 20.8°C at night.
Not quite — September is the 4th coolest month in Mackay, averaging 22.2°C.
For September in Mackay, pack light layers you can adjust through the day, with typical highs of 23.6°C and lows of 20.8°C.
Relative humidity in September averages 73% — moderately humid.
Average wind speed in September is 3.8 m/s. The windiest September on record averaged 4.9 m/s (1981).
The wettest September on record was 2010 with 154 mm. On average, September sees 19 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 Mackay 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.
