Melbourne's going be in for a fairly sleepless night.
The Bureau of Meteorology has forecast a minimum overnight temperature of 25 on Thursday night, leading into a maximum of 33 on Friday.
They've warned of "oppressive" conditions overnight as Melbourne cops a wave of humidity.
That's thanks to a band of tropical air moving across from Western Australia with a cyclone over the western coast.
It all comes with Melbourne set to swelter again tomorrow, reaching 33 degrees before northerly winds, showers and thunderstorms hit.
Melbourne will cop up to 10 millimetres of rain before a cool change sees the city cool down again.
The Bureau of Meteorology has warned thunderstorms are possible across the entire state, with severe storms - and possible supercell storms - likely in Gippsland and severe storms rated as possible in Melbourne.