Severe thunderstorms caused wind gusts above 130km/h in Victoria last night as the first in a pair of cold fronts swept across southeastern Australia.

The front produced showers and thunderstorms as it swept across South Australia, Tasmania, Victoria and southern NSW between Tuesday afternoon and Wednesday morning.

Tuesday's thunderstorms cause heavy showers and blustery winds in southern parts of South Australia, with small hail falling in parts of Adelaide.

As the system moved further east, thunderstorms intensified over Victoria and also developed in parts of Tasmania and southern NSW during Tuesday night and Wednesday morning.

Image: Rain and thunderstorms over Victoria at 2am AEST on Wednesday.

Impressively, more than 15,000 lightning strikes were detected within a 200 kilometre radius of Melbourne between 9pm on Tuesday and 9am on Wednesday. Some of these storms were severe, with wind gusts reaching 98km/h at Ballarat and 135km/h at Falls Creek.

By 9am on Wednesday, 10-30mm of rain had fallen over parts of South Australia, Victoria, northern Tasmania and southern NSW.

The first in this week's pair of fronts is now moving out into the Tasman Sea, although another front will pass over South Australia, Tasmania, Victoria and NSW between Wednesday afternoon and Thursday night. 

This system will cause further showers, thunderstorms and blustery winds. It will also be accompanied by a pool of cold air, leading to small hail and highland snow in some areas.

Sheep graziers warnings have been issued in parts of South Australia, Victoria and NSW as cold, wet and windy weather may threaten livestock during the next 24-48 hours. Further warnings may be issued in parts of southeastern Australia as this system unfolds.