Predictive radar provides a forecast of what the radar will look like in the coming minutes and hours and provides rapid updates of forecast rainfall for the coming hours.
First the model correlates the radar data with the observed rainfall across the BoM rainfall network. This allows the model to determine how much rainfall is occurring, relative to what is occurring on the radar. Next, this data is nested with the high resolution ACCESS-C model to provide the current atmospheric dynamics and generates two main outputs:
1) Single Image (Radar) View
This provides a loopable interface that forecasts the positioning of showers and storms over the coming minutes (and hours) depending on the model used. This is useful if you want to know where and when rainfall will occur along with indicative intensity. The model that updates every five minutes extends out to two hours, while the model that updates every 10 minutes extends to 12 hours.
2) Accumulated Forecast Rainfall Totals View
This provides a single image rainfall forecast of how much rainfall may occur in the specified time period. You can choose up to 12 hours in advance.
Both of these models update every five or ten minutes. Note that we recommend this be used as a guide only and you should consider the overall weather patterns and whether they are conducive to the rainfall totals being forecast.
Radar Observed Rainfall
For select radars (currently only Brisbane), you can also view radar derived rainfall. This merges the observed rainfall across the BoM rainfall network with the radar reflectivity to provide a graphical output of how much rain has fallen across the radar domain.
2D Radar Interface
The MetCentre 2D radar output is the same as the 3D output but allows for the image to be looped for up to 24 hours. You cannot show a 3D vertical slice in 2D mode - but can do this if you switch to 3D mode using the shortcut key.
MetCentre radar detects hail in thunderstorms. Each storm is provided a marker that corresponds to the size of hail in centimetres (if any) detected in the storm.
Important Note: The largest hail is not necessarily where the hail marker is placed - rather this is the largest hail occurring within the storm at the time. Using the Storm Paths feature or the 3D radar scans are useful tools to determine where the largest hail is falling.
A square marker indicates a storm that is unlikely to contain any hail. Triangles are used to display hail - with the scale listed in the image below.
Beside each storm marker is a small number (ie 14km). This is the height in kilometres of the storm. Typically higher storms are more intense than lower storms in the same environment and provides an additional guide to the intensity of storms.
MetCentre also provides the StormPredict function which plots the storm's movement in the next 15, 30, 45 and 60 minutes. This provides a guide of timing and positioning of the storm in the short term.