Autumn’s relief from rain

AUTUMN could be drier than average for some key agricultural areas of Tasmania according to the Bureau of Meteorology’s latest long-range forecast.

The BOM says Tasmania’s North-West has a 65-70 per cent chance of below average rainfall from March to May, while conditions across the rest of the state should remain neutral. Maximum temperatures across most of Tasmania have a 70 per cent chance of being higher than average for March to May.

The BOM says the forecast reflects the status and outlook for several climate drivers, including La Niña in decline and a positive Southern Annular Mode returning to neutral. The official record of Australia’s climate and notable weather events for 2022 includes a full analysis and description of last year’s rainfall, temperature, water resources, climate influences and more.

The report shows 2022 was a warm and wet year for most of Australia. Australia’s national mean temperature was 0.5C warmer than the 1961–1990 average, making 2022 the 22nd-warmest year on record, since national records began in 1910.

Annual maximum temperatures were above average for most of northern Australia, Tasmania and parts of the west coast, but below average for New South Wales, southern Queensland and parts of South Australia.

National rainfall was 26 per cent above the 1961–1990 annual average, making 2022 the ninth-wettest year on record since 1900.

The 2022–2023 La Niña was the third in a row. It is only the fourth time three consecutive La Niña events have been observed since 1900. There was a persistent pattern of above average monthly rainfall in the east and below average rainfall in the west from the beginning of the year until late autumn, and then returning in spring. The combination of below average rainfall in the West and above average rainfall in the East resulted in 2022 annual rainfall for Tasmania overall being close to average, at around 3 per cent below the 1961–1990 mean.

While overall 2022 was much drier than average for western Tasmania, the area had above average rainfall in May, June, August and November. The highest daily rainfall recorded in Tasmania during 2022 was 291.2 mm at Gray on January 7, which was a new January daily rainfall record for Tasmania.

Some sites had their highest daily rainfall on record on either May 6, when thunderstorms with heavy rain, lightning, and strong winds hit southern Tasmania, or October 14, when a slow-moving rain band brought heavy rainfall across northern Tasmania. Some sites had their highest total rainfall on record and others their highest rainfall for at least 20 years.

Mean maximum temperatures were in the warmest 10 per cent of annual records across the western half of Tasmania while maximum temperatures were close to average for parts of the East Coast. The mean maximum temperature for Tasmania as a whole for last year was 0.67C above the 1961–1990 average, the equal-10th warmest on record since 1910, and the highest since 2018. January, March, April and August all ranked in the top 10 warmest mean maximum temperatures.

The mean minimum temperature for Tasmania for 2022 was 0.46C above the 1961–1990 average, and also the highest since 2018.

Total rainfall for Hobart was 700mm, which is 114 per cent of the long-term average of 612.8.