Low Isles Lighthouse: weather history since 1889

Low Isles Lighthouse is a weather station located 3 m above sea level, 15 km from Port Douglas. Its records go back to 1889: 41 years of temperature are available up to 2025, along with rainfall and a comparison with two reference normals. Over 1991–2020 the annual mean temperature there is 26.5 °C, barely higher than over 1961–1990 (26.3 °C): a difference of 0.2 °C. The warmest year of the series is 2016 (27.3 °C) and the coldest 1972 (25.4 °C). The last complete year, 2025, ranks 4 out of 41, from warmest to coldest. Over 1961–2025, the annual mean temperature changes by +0.09 °C per decade. The station ranks 207 out of 227 stations, from the fastest rise to the slowest.

Annual mean temperature since 1889

The first ten years of the series (1968–1980) average 26.1 °C; the last ten (2015–2025) average 26.8 °C, a difference of +0.7 °C. Of the ten warmest years in the series, 5 fall after 1999. The warmest is 2016 (27.3 °C). The ten-year running mean peaks at 26.8 °C (2025) and bottoms out at 26.1 °C (1977).

Annual rainfall since 1889

On average 2104 mm of rain falls per year over the 119 documented years. The wettest year, 1981, received 3878 mm; the driest, 1902, only 817 mm, which is 4.7 times less. The 1991–2020 normal (2150 mm per year) is 149 mm (6.5 %) below the 1961–1990 one (2299 mm). Over 1991–2020, March is on average the wettest month (450 mm) and September the driest (34 mm). Between 1994 and 2025, 10 years out of 20 exceeded the series average.

Monthly normals: 1961–1990 against 1991–2020

The table compares, month by month, the mean temperature and the rainfall total of two thirty-year reference periods. The difference column shows what the recent period changes compared with the earlier one.

The largest temperature change is in September (+0.4 °C) and the smallest in May (−0.1 °C); over the year the mean difference is +0.2 °C, and 9 months out of twelve are warmer than before. For rainfall, the largest difference is in December (+17 mm) and the smallest in April (−70 mm).

Records at Low Isles Lighthouse

• Warmest year: 27.3 °C, in 2016
• Coldest year: 25.4 °C, in 1972
• Driest year: 817 mm, in 1902
• Wettest year: 3878 mm, in 1981
• Warmest month: 30.8 °C, in February 2016
• Coldest month: 21.4 °C, in July 1977
• Wettest month: 2148 mm, in January 1981
• Hottest day: 38.9 °C, on 26 November 2018
• Coldest day: 15.0 °C, on 26 June 1971
• Heaviest rain in one day: 470.2 mm, on 12 January 1981

1.9 °C separate the warmest year of the series from the coldest. Between the hottest and the coldest day on record, the range reaches 23.9 °C.

Temperature trend over 1961–2025

The regression line of annual mean temperature changes by +0.09 °C per decade between 1961 and 2025, about +0.6 °C over the whole period. That is slower than the median of the 227 stations (+0.19 °C per decade), by 0.10 °C per decade: the station ranks 207 out of 227.

The last 24 months against the 1991–2020 normal

Over the last 24 months (October 2024 to September 2026), 13 months out of 24 were warmer than the 1991–2020 normal for the same month; the mean departure is +0.2 °C. The highest departure was in July 2025 (+1.7 °C); the lowest, in September 2026 (−1.3 °C). The last twelve months add up to 2639 mm of rain, which is 123 % of the 1991–2020 annual normal (2150 mm).