A moderate risk is forecast from the central, north central and northern country forecast districts westwards.

The Mallee is the exception, with severe risk of thunderstorm asthma forecast.

People at increased risk of thunderstorm asthma have been advised to avoid being outside during thunderstorms, where possible, especially the wind gusts that come before a storm.

Those with increased risk should go inside and close the doors and windows. If the air conditioner is on, occupants should switch it to recirculate.

People should have reliever medication appropriately available in grass pollen season and be aware of how to use it, and should be alert to and act on the development of asthma symptoms in line with their asthma action plan or asthma first aid.

Ballarat is predicted to reach a top of 29 degrees today, with severe thunderstorms possible.

An 80 per cent chance of showers is predicted in the evening, with 10-20mm of rain expected today.

The gusty winds are expected to increase this evening.

For advice on thunderstorm asthma, visit betterhealth.vic.gov.au/health/conditionsandtreatments/thunderstorm-asthma

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