‘Bomb cyclone’ could bring major flash-flooding risks
Alex Mitchell, Sam McKeith and Farid Farid |

A “bomb cyclone” is set to dump more than 100mm of rain in the space of hours on Australia’s east coast, with the dynamic weather system bringing the threat of more flooding.
Millions of residents from Coffs Harbour to Bega, some 800km south, are in the path of a fast-moving, severe low-pressure system intensifying off the NSW north coast, set to bring damaging winds of up to 110 kilometres per hour.
The rapidly deepening system is known as a “bomb cyclone”, though the meteorological term is generally used sparingly so as not to incite panic, the Bureau of Meteorology says.

It has already sparked strong winds and hazardous surf with up to 120mm of rain expected to lash greater Sydney alone by Tuesday evening.
Major disruptions have been experienced at Sydney Airport, with 21 departure flights and 19 arrivals cancelled so far on Tuesday.
The weather bureau has issued flood watch warnings for southern parts of the mid-north coast, Hunter, Hawkesbury-Nepean, Sydney Illawarra Coast and Snowy catchments.
But flash flooding was the bigger risk due to the fast-moving nature of the weather compared, compared with the slow, pounding rain that inundated the mid-north coast earlier this year, the SES said.
“It is fast-moving and very different to recent events that we have seen in NSW, what we expect is the rain will be very rapid, it will be heavy and it will be short and sharp,” SES Deputy Commissioner Debbie Platz said.
“While we are concerned about riverine flooding, the most impact from this significant rainfall will be flash flooding, and this is likely to occur anywhere from Newcastle, Sydney and in the Illawarra region.”
The SES had more than 900 calls since 5am on Monday, and responded to more than 600 incidents.
Most of the calls were from people preparing properties for an inundation, but many were relating to damage caused by fallen trees.
The peak impact of the system is forecast to happen on Wednesday, and there’s a risk of flash flooding at Wallis Lake, near Taree on the mid-north coast.
Taree was one of the towns hard hit by floods in May that killed five people and damaged thousands of properties.
The mid-north coast region is an area of concern for emergency services because the soil is still saturated from the May floods.
The deepening coastal low would also result in dangerous beach conditions, coastal erosion and damage to the NSW coast from Seal Bay to Batemans Bay, the bureau warned.
Coastal communities were being urged to prepare ahead of the storm by tying down loose items and moving cars away from trees.
Rain rates and winds are expected to ease on Wednesday and ocean swells should ease on Thursday.
AAP