Tornado, epidemic thunderstorm asthma ‘on the cards’ for Victoria

Victoria is on high alert for thunderstorm asthma, with Melbourne bracing for an afternoon of wild weather.

A red alert has been issued amid fears parts of the state could experience an epidemic thunderstorm asthma event, similar to 2016’s tragedy which killed several people.

The Department of Health on Thursday declared an extreme risk in the western Wimmera district, while Melbourne, Mallee, the south west and north central districts were all deemed to be high risk.

Epidemic thunderstorm asthma is triggered of high grass pollen levels and a certain type of thunderstorm with strong winds and leaves those with asthma and hay fever at increased risk.

Health authorities say they should carry reliever medication over coming days.

Meanwhile, parts of the Mallee and Wimmera districts are preparing to be hit with damaging winds, large hailstones and heavy rainfall across Thursday afternoon, according to BoM.

Melbourne is also bracing for the possibility of severe thunderstorms, bringing northerly winds of up to 45 km/h, before easing in the late evening.

Melbourne is expected to receive between three and 10mm of rainfall throughout the afternoon and into the evening.

Thunderstorms, bringing northerly winds of up to 45 km/h, are forecast for Melbourne. Picture: David Geraghty

And the possibility of a tornado also remains “on the cards” for northern Victoria later in the week according to senior forecaster Rohan Smyth.

He told the Herald Sun a low pressure system was likely to envelope northern parts of the state in heavy rainfall, adding that an isolated tornado was possible.

“It looks like there will be pretty severe weather for northern Victoria this week,” he said.

“If we did see one (tornado) it would be quite isolated.”

While tornadoes are not necessarily common in Australia, Mr Smyth warned Victorians that they do occur in “remote areas” away from homes and townships.

There is no defined tornado season in Australia but can occur from spring to early summer.

BoM lists humid air set below the cloud base and strong wind shear low in the atmosphere as the key conditions for a tornado.

An isolated tornado is possible for Victoria’s north.

The seven-day forecasts, produced by the Bureau, for towns along the NSW-Victorian border report showers and possible storm activity on Thursday through to Saturday.

Temperatures will remain high, with Swan Hill expecting to reach 30C over the weekend.

Much of the state’s grass pollen levels sit at high though Melbourne and the south, east and west Gippsland remain extreme.

Melbourne Pollen Count co-ordinator and University of Melbourne associate professor Ed Newbigin said warmer conditions and increased rainfall were behind the increased levels.

“The peak is associated with the warmer weather our state is currently experiencing, levels will decrease as cooler temperatures come later in the week” he said.

Thursday will bring a high of 26 degrees with increasing shows.

Friday dips to a top of 22 degrees while a maximum 25 degrees is forecast for both Saturday and Sunday.