Research is still underway into ember storms. However we do know something of operational use:
- They are associated with deep flaming, but not headfires.
- They can be detected in multispectral linescanning imagery.
- They typically cover around 2 to 10 square kilometres, and move with the convective event across the landscape, at up to 35 km/hr.
- However within the storm wind speeds may reach much higher values.
- Primary embers come into the urban area from adjacent broadacre landuses. Secondary embers are created by mulch beds, gardens, etc in the urban area. Tertiary embers are produced by burning houses.
- In the absence of a wind change, the winds coming from burnt ground for the next six hours foster ember creation. New house ignitions are possible throughout this phase.
If an ember storms occurs, Situation Unit analysts need to review the potential timing with Operations Section staff.
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