Tasmania just had a very warm September night, the second night in a row that minimum temperatures across the state were reporting well above average. 

Warm air from mainland Australia has filtered down to the southeastern parts of the country, forced further south by strong winds from the interior associated with an approaching cold front.

As a result, most stations across the state reported overnight minimum temperatures for the 24 hours to 9am on Saturday that were 4-8 degrees above the long-term September average. St Helens even recorded its highest September minimum temperature (14.2 degrees) since the station began recording in 2001.

Flinders Island reported an overnight minimum temperature of 15.2 degrees on Saturday morning, equal to the high minimum temperature the day before, which marked the site's highest September minimum temperature in 17 years.

The cold front, which has now begun to cross the state, is bringing much cooler conditions due to cloud and rainfall. Daytime maximum temperatures that peaked at 8-10 degrees above the September average on Friday are expected to be at least 4-6 degrees lower on Saturday.

It has been a September of temperature extremes for the island state so far. Earlier in the week, various stations across the region reported their lowest September minimum in more than a decade, when a complex low pressure system and strong cold front made their way across the southeastern parts of the country.