Sydney weather LIVE: ‘Bombogenesis' triggers severe weather warning as rain sets in
What you need to know
By Josefine Ganko
Good morning and welcome to The Sydney Morning Herald's live coverage of today's weather, as a rapidly intensifying low-pressure system off the east coast brings heavy rain and wild winds to Sydney and around the state.
Here's what we know so far.
The Bureau of Meteorology has issued a severe weather warning for Sydney and much of the NSW coastline, from Moruya Heads in the South to Taree in the North, as a 'vigorous' coastal low offshore brings damaging, locally destructive winds and possible heavy rainfall.
In Sydney, heavy rain could bring six-hourly totals of 70 to 90 mm, while isolated downpours could see up to 120mm of rainfall.
Wind gusts are already reaching up to 50km/h, with speeds between 60-70km/h expected to set in on Tuesday afternoon, with peak gusts of up to 110km/h
Destructive wind gusts in excess of 125km/h could hit exposed coastal areas from Bondi to Wollongong from later today.
Flash flooding is possible for the coastal fringe south of Seal Rocks on the Mid North Coast and north of Ulladulla on the South Coast.
NSW SES deputy commissioner Debbie Platz advised households to secure outdoor furniture, clear gutters, move vehicles away from large trees and download the Hazards Near Me app to stay up to date.
The rapid intensification of the low into a fierce weather system, dubbed 'bombogenesis' by meteorologists, is a rare event most often seen during winter. You can read more about the science of the phenomenon here.
The forecast movement of the coastal low would see damaging winds and heavy rain persist into Wednesday.
6.52am
'Be very vigilant and very prepared': SES advice as wild weather arrives
By Angus Dalton
The SES has pre-deployed 395 volunteers across the coast and positioned high-clearance vehicles to Kiama, Albury, Hawkesbury, Maitland and Dungog, as NSW braces for the latest wild weather event.
Emergency vehicles and helicopters were also deployed to Taree, which is still reeling from May's flood disaster.
'This is a time for our communities across NSW to be very vigilant and very prepared. We're looking at thunderstorms, rain, strong winds, coastal erosion and damaging surf,' SES deputy commissioner Debbie Platz said.
Platz urged people to download the Hazards Near Me app, secure outdoor furniture and trampolines, clear gutters and move vehicles away from large trees.
The science behind the 'bombogenesis' phenomenon
By Angus Dalton
The rapid intensification of the low into a fierce weather system, dubbed 'bombogenesis' by meteorologists, is a rare event most often seen during winter.
'Over the next 24 hours or so, we will see the low form quite deep, quickly, and the central pressure dropping significantly, somewhere in the order of 20 to 30 hectopascals,' the bureau's Daniel Hayes said on Monday.
Loading
That plunge in pressure easily meets the threshold for an east coast low, but another low-pressure system stewing further out to sea will interact with the coastal system, potentially siphoning off energy and reducing the potential for the wide-scale impacts that would define an east coast low.
Forecasting the interaction between the two low-pressure systems is tricky.
'The two can just dance around each other and both survive but pull energy out each other. Or they could merge, and you eventually get one system that's stronger,' Hayes said.
The two lows could undergo the Fujiwhara effect, where two systems rotate around each other, according to Weatherwatch meteorologist Anthony Cornelius. That would further complicate forecasting and may push the bad weather into three-day event, he said.
6.26am
What you need to know
By Josefine Ganko
Good morning and welcome to The Sydney Morning Herald's live coverage of today's weather, as a rapidly intensifying low-pressure system off the east coast brings heavy rain and wild winds to Sydney and around the state.
Here's what we know so far.
The Bureau of Meteorology has issued a severe weather warning for Sydney and much of the NSW coastline, from Moruya Heads in the South to Taree in the North, as a 'vigorous' coastal low offshore brings damaging, locally destructive winds and possible heavy rainfall.
In Sydney, heavy rain could bring six-hourly totals of 70 to 90 mm, while isolated downpours could see up to 120mm of rainfall.
Wind gusts are already reaching up to 50km/h, with speeds between 60-70km/h expected to set in on Tuesday afternoon, with peak gusts of up to 110km/h
Destructive wind gusts in excess of 125km/h could hit exposed coastal areas from Bondi to Wollongong from later today.
Flash flooding is possible for the coastal fringe south of Seal Rocks on the Mid North Coast and north of Ulladulla on the South Coast.
NSW SES deputy commissioner Debbie Platz advised households to secure outdoor furniture, clear gutters, move vehicles away from large trees and download the Hazards Near Me app to stay up to date.
The rapid intensification of the low into a fierce weather system, dubbed 'bombogenesis' by meteorologists, is a rare event most often seen during winter. You can read more about the science of the phenomenon here.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
News.com.au
9 hours ago
- News.com.au
Early morning track inspection to decide Warwick Farm's fate
A 6am track inspection on race morning will determine if Wednesday's Warwick Farm meeting goes ahead as a 'cyclone-like' storm continues to lash the New South Wales coast. Tuesday's meeting at Newcastle's Beaumont track was forced to be abandoned while Rosehill Gardens trials were moved to Friday on a wet and windy day on the east coast. Warwick Farm is due to hold a seven-race card with the Western Sydney track rated a Heavy 9 on Tuesday afternoon. The track had received 25.8mm of rain in the 24 hours leading up to 3pm on Tuesday. As much as 25mm has been forecast by the Bureau Of Meteorology in the Liverpool area on Wednesday. The Warwick Farm card is due to begin at 12.50pm with the running of the Captivant @ Kia Ora Plate.
West Australian
11 hours ago
- West Australian
Bomb cyclone updates: NSW, Sydney lashed with wild winds and rain as itensifying system moves in
A fast-approaching and intensifying weather event dubbed a 'bomb cyclone' is on the doorstep of the NSW coast, with almost the entire State's eastern coastline under warning from the SES and the NSW Government. From midday, Sydneysiders near the coastline were told to 'stay indoors' by the NSW SES. Intense rain in city areas has begun, with regional areas copping an aggressive lashing of rain and wind. On Tuesday, the NSW SES raised the alarm over dangerous winds and intense rain. 'The NSW SES is advising people in the following areas to STAY INDOORS due to damaging winds, destructive winds: Coastal Areas between Bulli and Collaroy,' one warning said. In the Greater Sydney area, warnings are in place in areas including Liverpool, Milperra, Penrith, Wallacia, Windsor, North Richmond and Camden 'Flash flooding is a high risk throughout the East Coast, where heavy rain could cut roads without warning. If you do need to be on the roads, drive with caution as we are expecting to see flash flooding by the afternoon commute,' the SES said. The system, however, stretches far beyond Greater Sydney. From Bega on the NSW south coast, to Coffs Harbour on the north, residents are being warned of 'rapid' rain bursts. 'This system is fast-moving, different to recent events, and will bring rapid, heavy, short and sharp rain bursts,' NSW SES Deputy Commissioner Debbie Platz said on Tuesday. The BOM (Bureau of Meteorology) has warned of 120mm falling in just six hours in parts of Sydney and the Illawarra, and has told coastline residents to brace for 125km/h winds. 'A severe weather warning is current for Heavy rainfall, which may lead to flash flooding, is developing in the Illawarra south of Wollongong later today, extending southwards to reach Bega in the South Coast by evening,' the BOM said on Tuesday morning. Emergency services are reminding Australians not to drive, walk, swim or play in floodwater. 'People should stay away from flooded drains, rivers streams and waterways,' the NSW SES said on Tuesday. As the 'bomb cyclone' weather front ramps up, safety officials have forced Sydney Airport to scale back to one operational runway amid flight cancellation chaos. Millions of residents are being affected by the massive storm front that is hammering large areas of the east coast as Virgin and Jetstar cancel flights and commuters are warned by the SES about the afternoon journey home. Airservices Australia, the government body responsible for making air traffic safety calls, made the call to shut all but one runway. 'Airservices Australia has now enacted single runway operations at Sydney Airport due to strong south-westerly winds,' a statement said. 'This adheres to our International Civil Aviation Organisation (ICAO) safety regulations for runway usage amid inclement weather. 'Safety is Airservices' No.1 remit; this decision is purely weather and safety-related to safeguard the travelling public.' Dubbed a 'bomb cyclone,' the system is technically known as bombogenesis, which is a rapidly developing storm that forms when atmospheric pressure drops sharply over a short period, creating an unstable air mass. The exact threshold for this pressure drop varies with latitude. In the Tasman Sea, it ranges from a fall of 18 hectopascals in 24 hours near Tasmania to 13 hectopascals closer to the NSW-Queensland border. This particular system is forecast to drop between 22 and 24 hectopascals per day, easily surpassing the bombogenesis threshold. The result? Torrential rain, destructive winds, and dangerous surf conditions across much of NSW. The Bureau's Community Information Lead, Angus Hines, said that the current event is shaping to bring most of the rainfall south, but warned it could take a subtle shift to bring some heavier rain into the mid north coast.
Perth Now
11 hours ago
- Perth Now
‘Stay indoors': NSW bomb cyclone arrives
Experts warn of a powerful storm cell that is set to smash the East Coast, millions of residents urged to prepare now. A fast-approaching and intensifying weather event dubbed a 'bomb cyclone' is on the doorstep of the NSW coast, with almost the entire State's eastern coastline under warning from the SES and the NSW Government. From midday, Sydneysiders near the coastline were told to 'stay indoors' by the NSW SES. Intense rain in city areas has begun, with regional areas copping an aggressive lashing of rain and wind. Residents across an 800km stretch of coastline are bracing for severe weather that's due to dump up to 200mm of rain. Credit: Bianca De Marchi / AAPIMAGE On Tuesday, the NSW SES raised the alarm over dangerous winds and intense rain. 'The NSW SES is advising people in the following areas to STAY INDOORS due to damaging winds, destructive winds: Coastal Areas between Bulli and Collaroy,' one warning said. NSW SES warning on July 1. Credit: NSW SES In the Greater Sydney area, warnings are in place in areas including Liverpool, Milperra, Penrith, Wallacia, Windsor, North Richmond and Camden 'Flash flooding is a high risk throughout the East Coast, where heavy rain could cut roads without warning. If you do need to be on the roads, drive with caution as we are expecting to see flash flooding by the afternoon commute,' the SES said. The system, however, stretches far beyond Greater Sydney. Surfers are seen in the water at Bronte in Sydney, Tuesday, July 1, 2025. Credit: Bianca De Marchi / AAPIMAGE From Bega on the NSW south coast, to Coffs Harbour on the north, residents are being warned of 'rapid' rain bursts. 'This system is fast-moving, different to recent events, and will bring rapid, heavy, short and sharp rain bursts,' NSW SES Deputy Commissioner Debbie Platz said on Tuesday. The BOM (Bureau of Meteorology) has warned of 120mm falling in just six hours in parts of Sydney and the Illawarra, and has told coastline residents to brace for 125km/h winds. 'A severe weather warning is current for Heavy rainfall, which may lead to flash flooding, is developing in the Illawarra south of Wollongong later today, extending southwards to reach Bega in the South Coast by evening,' the BOM said on Tuesday morning. Emergency services are reminding Australians not to drive, walk, swim or play in floodwater. 'People should stay away from flooded drains, rivers streams and waterways,' the NSW SES said on Tuesday. As the 'bomb cyclone' weather front ramps up, safety officials have forced Sydney Airport to scale back to one operational runway amid flight cancellation chaos. Millions of residents are being affected by the massive storm front that is hammering large areas of the east coast as Virgin and Jetstar cancel flights and commuters are warned by the SES about the afternoon journey home. Airservices Australia, the government body responsible for making air traffic safety calls, made the call to shut all but one runway. 'Airservices Australia has now enacted single runway operations at Sydney Airport due to strong south-westerly winds,' a statement said. 'This adheres to our International Civil Aviation Organisation (ICAO) safety regulations for runway usage amid inclement weather. 'Safety is Airservices' No.1 remit; this decision is purely weather and safety-related to safeguard the travelling public.' Dubbed a 'bomb cyclone,' the system is technically known as bombogenesis, which is a rapidly developing storm that forms when atmospheric pressure drops sharply over a short period, creating an unstable air mass. The exact threshold for this pressure drop varies with latitude. In the Tasman Sea, it ranges from a fall of 18 hectopascals in 24 hours near Tasmania to 13 hectopascals closer to the NSW-Queensland border. This particular system is forecast to drop between 22 and 24 hectopascals per day, easily surpassing the bombogenesis threshold. The result? Torrential rain, destructive winds, and dangerous surf conditions across much of NSW. The Bureau's Community Information Lead, Angus Hines, said that the current event is shaping to bring most of the rainfall south, but warned it could take a subtle shift to bring some heavier rain into the mid north coast.
