Hobart is having its wettest autumn in 15 years, despite receiving below average rainfall during the first two months of the season.

Like much of southern Australia, Hobart received less rain than usual during March and April. The city's 68.6mm in this time was just over two thirds of its long term average for the first two months of autumn.

This drier than usual weather persisted into the start of May, until a single night of heavy rain more than made up for the city's early season rainfall deficit.

Hobart received a whopping 129.2mm of rain during the 24 hours to 9am on Friday 11th May, most of which fell on Thursday night. This was its highest daily rainfall total since 1960 and the heaviest on record during May, triggering flash flooding in parts of the city.

This deluge and a few other spots of rain during May have brought the city's running total for autumn up to 212mm, as of 9am on Monday. This is about 70mm above its long term seasonal average and makes this Hobart's wettest autumn since 2003.

While the city is forecast to receive a few light showers during the final days of May, they aren't likely to be enough to beat the season's total of 222.4mm from 2003.

Hobart's wettest autumn on record saw 359.9mm fall during 1960 and the driest was 40.2mm in 2002.