The epidemic thunderstorm asthma forecast operates during the Victorian grass pollen season (1 October – 31 December).
Maps of current epidemic thunderstorm asthma forecast
Today
Tomorrow
Forecasts are issued twice daily during the grass pollen season (October to December). They cover three consecutive days and use a colour-coded scale: green (low), orange (moderate) and red (high).
For up to date information on epidemic thunderstorm asthma risk visit the VicEmergency website or download the VicEmergency app from Google Play or the App Store and set up a 'watch zone'.
Three day epidemic thunderstorm asthma forecast by region
What do the forecasts mean?
The epidemic thunderstorm asthma forecast system will operate between 1 October and 31 December. It combines the forecasting of a certain uncommon type of thunderstorm and forecasting grass pollen levels across Victoria.
It spans three days (today, tomorrow and the day after) and uses a colour-coded scale from low to high risk: green (low), orange (moderate) and red (high).
- A low risk (green) forecast means that the elements necessary for an epidemic thunderstorm asthma event are not expected and an event is unlikely.
- A moderate risk (orange) forecast means that one of the elements necessary for an event may be present (i.e. a high pollen forecast or a severe thunderstorm with strong winds) and there is a moderate chance of an epidemic thunderstorm asthma event occurring.
- A high risk (red) forecast means that there is a high pollen forecast and severe thunderstorm(s) with strong winds are likely to be present increasing the risk of an epidemic thunderstorm asthma event occuring.
The forecast is published on VicEmergency - emergency.vic.gov.au/prepare/#thunderstorm-asthma-forecast
Forecasts are not a formal 'warning' and are designed to inform people at risk that they should be prepared. The forecast only indicates whether the chance of an epidemic thunderstorm asthma event occurring is increased – a higher forecast does not mean than an event is certain to happen, nor does a lower forecast mean that an event will not happen.
What should I do on days with increased risk?
People should be aware of the heightened risk of thunderstorm asthma in general throughout the grass pollen season and be appropriately prepared. The forecast should not replace appropriate prevention and good asthma and hay fever management, which is the best way to protect yourself from thunderstorm asthma.
The forecasting system is also not designed to forecast the risk of individuals suffering asthma and hay fever symptoms, which occur every year during the grass pollen season.
People with current, past or undiagnosed asthma or hay fever are considered to be at risk. Having both asthma and hay fever or poorly controlled asthma increases the risk further. Those at increased risk should:
- avoid exposure to any storms that may emerge, especially the wind gusts that precede them
- have a reliever appropriately available (as discussed with your doctor or pharmacist)
- remind themselves of their asthma action plan and have practical knowledge of the four steps of asthma first aid.
On a high risk day the department will issue up-to-date relevant advice and warnings on the VicEmergency warning platform.
The forecast for the current day is only updated once, at approximately 12:30pm, any further updates (such as public advice and warnings) will be posted on the VicEmergency website and app.
How is epidemic thunderstorm asthma forecast?
The risk of an epidemic thunderstorm asthma event occurring is forecast daily during the Victorian grass pollen season (typically 1 October to 31 December).
The department has worked with the Bureau of Meteorology and a number of partner organisations to develop the forecasting system. The system combines weather and pollen observations and data to forecast the risk of an epidemic thunderstorm asthma event. The forecasting system is not designed to forecast the risk of individual increases in asthma and hay fever symptoms, which occur every year during the grass pollen season.
The science of epidemic thunderstorm asthma forecasting is new and, as with all forecasts, there is an element of uncertainty – as such, it should not be relied upon as a primary measure to prevent thunderstorm asthma. A high risk forecast does not mean an epidemic thunderstorm asthma event is certain to occur, rather that the chances of it occurring are increased and it should be considered seriously - those at risk and their families should be prepared. Likewise, the forecast may sometimes underestimate the risk. Therefore, it is important for those with asthma or hay fever to see their doctor or pharmacist to review their current medication, update their asthma action plan/hay fever treatment plan and learn asthma first aid.
The forecasting system serves two purposes:
- to enable health and emergency service systems to be suitably prepared on days of increased risk
- to raise community awareness of possible events so, where possible, those at increased risk can take action to reduce the health impacts of a potential event.
For more information on Victoria's epidemic thunderstorm asthma forecast system, view our frequently asked questions.
Map of Victorian forecast districts
View a map of Victorian districts below or access the
map website. A list of local government areas is also provided below.