Tasmania recorded its warmest May daytime temperatures on record last month, while a gauge in the state’s north-east logged the wettest day of anywhere in Australia.
The state’s mean maximum temperature for May was 14.64 degrees, 2.24 degrees above the long-term average and beating the previous record anomaly of 1.87 degrees set in 2007, according to the Bureau of Meteorology’s monthly climate summary.
Almost the entire state recorded its highest May daytime temperatures since statewide records began in 1910.
Hobart set its own record, with an average maximum of 17.38 degrees, just past the 17.30 degrees from 2007.
The warm spell capped Hobart’s warmest autumn on record, with a March-to-May average maximum of 19.43 degrees.
Weatherzone meteorologist Ben Domensino said unusually high pressure over New Zealand was a key driver.
“This blocking pattern also caused air to flow over abnormally warm water in the Tasman Sea before reaching Tasmania, further insulating the state from pre-winter cold spells,” he said.
The heat peaked on May 1, when hot air from the interior was pushed over the south-east ahead of a cold front.
Tasmania averaged 21.6 degrees statewide, its hottest May day on record.
Hobart Airport reached 27.5 degrees, the second-highest May temperature ever recorded in the state.
The warmth extended across the south-east, with Victoria and New South Wales both recording their second-warmest May on record, behind only 2007.
Conditions turned wet late in the month. On May 27, a low pressure system moved through Bass Strait and met moist air dragged south by a trough over the mainland, driving onshore winds along the east coast.
Gray, in the state’s north-east, recorded 222.0mm in the 24 hours to 9 am on May 28.
That was the fourth-highest daily May rainfall ever recorded in Tasmania and the wettest day recorded anywhere in Australia during May.
The bureau issued moderate to minor flood warnings for the St Pauls and South Esk rivers.
Despite the late deluge, Tasmania finished May drier than usual overall, with rainfall 20% below average.
The wet weather fell mainly in the east, while the west of the state remained dry.
