A deepening low pressure system over the Tasman Sea is causing severe weather in parts of Victoria, New South Wales and the ACT, with damaging winds, heavy rain, thunderstorms, large waves and highland snow.

Severe storms in NSW on Thursday

A cold front passing over southeastern Australia on Thursday caused rain and storms to spread over NSW. Behind this front, cold air and blustery southerly winds caused temperatures to plummet in Vic and Tas.

Thursday’s thunderstorms caused wind gusts of up to 115 km/h at Dubbo and above 90 km/h at Mudgee, Coonamble and Cobar during the afternoon. As the storms move further east late in the day, they dropped heavy rain and large hail in parts of Sydney.

These storms also produced a large amount of lightning. Weatherzone’s Total Lightning Network detected more than 330,000 lightning pulses within a 400 km radius of Oberon during the 12 hours ending at 8 pm AEDT on Thursday.

More severe weather on Friday

Severe weather will continue to batter southeastern Australia on Friday as a low pressure system deepens rapidly over the western Tasman Sea.

Rain and flooding

Rain will continue to soak areas from southern Vic up to central NSW on Friday. The heaviest falls are expected to occur in Vic’s East Gippsland district, where rain rates could reach 60 to 80 mm in six hours, which is enough to cause flash flooding.

Some of Friday’s precipitation will fall as snow in elevated areas of northeast Vic and southeast NSW.

Wind and waves

The intensifying low will cause powerful southerly winds over exposed areas of southeastern Australia on Friday. Severe weather warnings have been issued for damaging winds in parts of central and eastern Vic and southeast and central NSW, including parts of the ACT.

The ferocious winds will create huge waves that will first build to the east of the Bass Strait on Friday morning before spreading up the NSW coastline on Friday and Saturday. This surge of southerly swell will cause waves of 4 to 8 metres along the NSW coast, with damaging surf expected to cause coastal erosion from the Vic border up to about Seal Rocks.

Image: Forecast significant wave height at 1am AEDT on Saturday. Source: Weatherzone.

After battering southeastern Australia on Friday, the low pressure system will move out over the Tasman Sea on Saturday. This will allow rain and wind to ease on Saturday as the low moves further offshore, with swell easing from Sunday.