Victoria's chief health officer warns of thunderstorm asthma risk

Large parts of eastern and northern Victoria are being warned of heightened thunderstorm asthma conditions today.

Chief Health Officer Caroline McElnay is urging Victorians to act on asthma symptoms such as wheezing, breathlessness or persistent coughing.

The Bureau of Meteorology has forecast a low to move across eastern Victoria during the afternoon and evening.

Eastern and northern Victorians are being urged to be on alert for thunderstorm asthma today.

All three Gippsland districts and the Northern Country region, which covers Shepparton and Bendigo, are at elevated risk due to a combination of high grass-pollen levels and a certain type of thunderstorm.

Chief Health Officer Caroline McElnay urged Victorians to act on symptoms such as wheezing, breathlessness, chest tightness or persistent coughing.

"It's the combination of the high winds that come with the thunderstorm as well as the high grass-pollen levels," she said.

"The wind splits the pollen up into smaller pieces [so] it's more likely to get into people's lungs, and that can trigger an asthma attack.

"So we're putting out a warning that the risk is higher for those areas, and therefore people who have asthma should make sure that they take their reliever medication with them at all times.

"Particularly when the storm is coming close to you, avoid the wind gusts that happened before and during the storm."

The Bureau of Meteorology is forecasting a low-pressure trough to approach from the west, moving over western Victoria early on Saturday and reaching central districts in about the middle of the day before crossing the state's east during the afternoon and evening.

Thunderstorm asthma events have been known to put intense pressure on health systems, most notably in November 2016, when Melbourne was subject to the world's largest thunderstorm asthma event.

Ten people died and thousands sought urgent medical attention.

One in 10 Australians has asthma, an in curable, long-term lung condition that can make it difficult to breathe.

Dr McElnay said early November was generally a time of heightened thunderstorm asthma conditions in Victoria, although it remained unclear whether this spring was more perilous than usual.

"It's too early for us to say at this point in time what the season is going to be like, but certainly we've not had two weekends in a row where we're putting out a high alert for thunderstorm asthma," she said.

"Our experts in the pollen monitoring have certainly advised us that there's more grass pollen around this year because it was a wetter winter and spring.

"So that may mean we're more likely to see these high forecast events."