Bureau of Meteorology: Severe Weather Warning Education

The table below details the criteria for issuing Severe Thunderstorm Warnings and Severe Weather Warnings.

The following link provides education resources on severe weather warning services.
Severe Thunderstorms Brochure

A Severe Thunderstorm Warning is issued if the severe phenomena are directly caused by the thunderstorm.

Severe weather in a tropical cyclone will be covered by the Tropical Cyclone Warnings.

During the tropical wet season, many thunderstorms exhibit severe phenomena, notably wind gusts and intense rain leading to flash flooding.  In tropical zones, the possibility of severe gusts or heavy rain will be mentioned in the Bureau's normal forecasts. Predicting which storm will produce these phenomena is difficult.  Severe Thunderstorm Warnings, where provided, will be restricted to more long-lived lines of thunderstorms (squall lines) that are expected to cause destructive wind gusts (greater than 120km/h).

Intense rainfall can deposit a large amount of water over a small area in a small time period.  This water can cause localised flooding that can rise rapidly in a matter of minutes often catching people off-guard, which leads to a dangerous situation.  Torrents of water can wash people, cars and even buildings away at short notice.

Riverine flooding is generally the result of widespread rain, causing water over large areas to collect in streams and rivers, which overflow.  These floods generally rise at a slower rate and although quite devastating, do rise at a rate that usually allows for managed escape.  Riverine floods are still dangerous as flowing water can still wash people, cars, etc away.  Also, breaches of levees or other barriers may cause localised flash flooding as water flows through the breach into previously dry land.

Severe Weather Warning
Severe Thunderstorm Warning
Superseded Warnings (Warnings replaced in the warnings restructure of 16 Nov 2004)

Note that other specialised products are provided to key stakeholders - like emergency service organisations. These generally provide detailed technical information to assist these organisations in planning disaster mitigation strategies.

Return to Main Warnings Information Page

Last updated October 2004