A southern low pressure system and a La Niña ALERT are not warmly welcomed news for the NSW North Coast, as it's possible some heavy rain events could occur between now and January 2022

 

Ch 9 News on 13 October 2021 reported; Meteorologists warn a "beast from the south" will produce a dangerous mix of heavy rain, severe thunderstorms, damaging winds, hail and snow over Australia's south-east as a week of spring wet weather continues.

Coastal catchments with much of their historical and ongoing development situated on floodplains are particularly vulnerable when a climate driver triggers prolonged or frequent heavy rainfall events, as widespread or flash flooding can result. Property damage, stock & crop losses may occur and, sometimes the deaths of people caught in flood waters. 

Similarly low pressure systems can batter coastal catchments.

WeatherZone tweeted this.....

Here is the forecast accumulated rain over the next four days. 🌧

Flood watches have been issued in TAS and VIC, where some places could see more than 100mm by Sunday. Localised flooding is also likely in NSW and QLD from severe storms, especially on Thursday. pic.twitter.com/sVfxdgoCNU

— Ben Domensino (@Ben_Domensino) October 13, 2021

This was the Australian Bureau of Meteorology (BOM), on 12 October 2021:

The Bureau's ENSO Outlook has been raised to La Niña ALERT. This is due to continued cooling in the tropical Pacific Ocean and an increase in the number of climate models showing sustained La Niña conditions over summer. Historically, when La Niña ALERT criteria have been met, La Niña has subsequently developed around 70% of the time. A 70% chance of an event is approximately triple the normal likelihood. La Niña events increase the chances of above-average rainfall for northern and eastern Australia during spring and summer.

Most oceanic and atmospheric indicators of ENSO are currently within the ENSO-neutral range, but some have shifted towards a La Niña-like state. Sea surface temperatures in the central tropical Pacific Ocean are neutral, but have cooled over the past three months and are supported by cooler than average waters beneath the surface. Some atmospheric indicators, such as the Southern Oscillation Index (SOI) and cloudiness near the Date Line, are approaching La Niña levels. Six of the seven international climate models surveyed by the Bureau meet La Niña criteria from November.

A weak negative Indian Ocean Dipole (IOD) event continues. Most models suggest the negative IOD event will ease to neutral levels in late spring. A negative IOD increases the chances of above-average spring rainfall for much of southern and eastern Australia, while a neutral IOD has little influence on Australian climate.

The Madden–Julian Oscillation (MJO) has been active over the Maritime Continent since late September. The MJO is forecast to progress eastwards over the coming week and weaken as it approaches the western Pacific. While the MJO is over the Maritime Continent region, it encourages enhanced rainfall over the tropics to the north of Australia.

The Southern Annular Mode (SAM) index has been neutral for the past week after 5 to 6 weeks at positive levels. While it is forecast to remain neutral for the coming week, it is expected to return to generally positive levels from October to December. A positive SAM during spring typically brings wetter weather to eastern parts of Australia, but drier than average conditions for western Tasmania.

Climate change continues to influence Australian and global climate. Australia's climate has warmed by around 1.44 °C for the 1910–2019 period. Rainfall across northern Australia during its wet season (October–April) has increased since the late 1990s. In recent decades there has been a trend towards a greater proportion of rainfall from high intensity short duration rainfall events, especially across northern Australia.......

The El Niño–Southern Oscillation (ENSO) is currently neutral.

However, all of the seven international climate models surveyed by the Bureau anticipate further cooling of tropical Pacific sea surface temperatures. All models surveyed indicate La Niña thresholds may be met during November. Six of the seven models indicate this cooling will be sustained at La Niña levels until at least January 2022—long enough to meet minimum La Niña event criteria (i.e. at least three months). Four models continue the event into February, but by March only two models continue to meet the threshold.

La Niña typically enhances spring rainfall in northern and eastern Australia.

BACKGROUND

“Major floods frequently isolate towns, and can cause death, major disruptions to road and rail links, the evacuation of many houses and business premises, and the widespread flooding of farmland…..

As we are specifically concerned with major flooding near the coast, we consider a flood to be major if (i) it causes inundation of a river within approximately 50 km of the coast or (ii) if there is non-riverine flooding overland near the coast, from the active part of a weather system, that extends at least 20 km along the coast. In (i) extreme rainfall extends well into the hinterland and the upper reaches of the river catchments, causing a flood that drains down the river systems to coastal areas. In (ii) extreme rainfall is confined to the coast and floods form directly over the coastal area rather than propagating down the river systems. At major coastal centres there are official river height records that determine whether a flood meets the major level or not, and we have used this data available.” [ResearhGate, Callaghan J & Scott, S in Australian Meteorological and Oceanographic Journal 64(3):183-21 DOI:10.22499/2.6403.002]

On Australia’s eastern shores East Coast Lows are also often a trigger for heavy rainfall and widespread flooding. Sea surface temperature gradients associated with the warm eddies of the East Australian Current are an important contributor to the development of the lows.

Berejiklian Coalition Government washing its hands of any responsibility for the past 74 years of urban development on NSW floodplains?

Macleay River flooding from the air
IMAGE: Macleay Argus, 21 March 2021

In all but ruling out largescale buybacks of housing on NSW floodplains, a cynical Berejiklian Coalition Government is obviously feeling safely protected by the 1979 Environmental Planning and Assessment Act s2.28 liability exemption clause.

As well reassured there will be no blowback on local government due to protections for councils and staff inserted by a predecessor, the Fahey Coalition Government, in the 1993 NSW Local Government Act s731-s733 liability exemption clauses covering flooding and bushfires. Later helpfully reinforced by another predecessor the Keneally Labor Government in 2011, to cover indemnity against lack of action or planning decisions taken that were known to increase risks of climate change impacts.

In between these two pieces of legislation, the Carr Labor Government even tossed in the 2002 Civil Liability Act to add to the circumstances in which liability could generally be avoided.

The proof of the ease with which the Berejiklian Government is passing the buck back to homeowners for the past 74 years of urban development on floodplains is found in the current Coalition state government’s response to widespread flooding in New South Wales during March 2021.

Vulnerable communities in north-east NSW might think on the Berejiklian Government’s reluctance to seek genuine solutions to increasing floodplain risks due to climate change-induced alterations to seasonal weather patterns, the contribution to flooding made by erosive wave patterns with rising seas and, natural disaster events.

The Guardian, 10 April 2021:

Urban planners and water scientists have urged the New South Wales government to offer to buy back thousands of homes in flood-prone areas of western Sydney, as overdevelopment sets a trajectory for the number of uninsurable houses in the city to surge.

Infrastructure NSW has acknowledged residential property buybacks would be “effective” to mitigate flood risk in the Hawkesbury-Nepean Valley and across western Sydney, but the government agency has said such a scheme would incur “very significant social and economic costs”.

The call for buybacks, from the urban thinktank the Committee for Sydney, followed floods in March that inundated parts of western Sydney after Warragamba Dam spilled over, and wreaked havoc across NSW and south-east Queensland.

By Tuesday, the insurance bill for the floods had risen to $537m, from 35,845 claims, as affected residents continue to lodge damage with their insurers.

The Committee for Sydney’s resilience director, Sam Kernaghan, believes the insurance bill for March’s floods will rise to $2bn and says it will ultimately cost the NSW government too as it foots the bill for emergency services and recovery relief services as insurer of last resort.

The committee has issued a plea for the state’s recovery and rebuilding to seriously consider not “reestablishing homes, farms and businesses in this increasingly hazard prone location”.

“The bill will be enormous… [instead] we have an opportunity to use that money differently to support western Sydney residents and businesses for the long term,” the committee said, calling for the billions to be spent rebuilding to focus on a voluntary home purchasing scheme “that supports residents to move out of the way of the floods”.

“Funded by state government, this scheme would provide a mechanism for residents to sell flood risk properties to the government at market rates,” the committee said, noting a similar scheme put in place after the 2011 Queensland floods that saw Brisbane city council purchase $35m in flood-affected land, with properties transformed into parkland.

Kernaghan believes there is a strong argument to buy back about 5,000 to 7,000 homes in western Sydney – not all of the 55,000 to 77,000 that are estimated to need to evacuate during a one in 100-year flood event….

The committee is also calling for more thorough mapping of flood plains in Sydney to help long-term planning, as well as transferrable development rights similar to the model used in Norfolk, Virginia – a US city sinking more than 3.5mm a year – and strengthening evacuation routes to help existing communities in the Hawkesbury-Nepean floodplain…..

“If nothing is done to address this escalating risk from extreme weather and climate change, by 2100 Sydney will have a projected 91,000“uninsurable” addresses — the most of any city — with over five times as many uninsurable properties in 2100 than in 2019,” he said.

“Regardless of what Sydney decides to do, the question before western Sydney is this: do we really want to continue to put people in the flood plain? Previous governments ignored the science, hoping it would be all right. The result has been tragedy for thousands of people.

“The recent floods should make it clear it is not responsible to put people where they will be exposed to this level of harm ... It’s time for Sydney to look at a long-term plan to reduce the cycle of disaster.”

Dr Ian Wright, a water scientist at Western Sydney University who previously worked as a scientist for Sydney Water studying the Sydney basin flows, also supports the concept of home buybacks.

Wright has been a vocal part of the chorus of water scientists warning of the impact overdevelopment had on the recent floods.

As large swathes of western Sydney that were previously bushland and soil – which absorb water before flooding – had been paved over and roads and hard surfaces built to support new suburbs in recent years, there is increased runoff and flood risk to communities lower down. Residents in western Sydney complained of this issue as their homes, which had seen out previous floods, succumbed to the recent deluge…..

The NSW planning minister, Rob Stokes, referred the Guardian’s inquiries to environment minister Matt Kean’s office, which referred it to Infrastructure NSW.

An Infrastructure NSW spokeswoman said the government had considered buybacks to mitigate flood risk, including in its Hawkesbury-Nepean flood strategy released in 2018.

“However, in the Hawkesbury-Nepean Valley, large-scale compulsory acquisition across entire suburbs would be necessary for this to be effective and would have very significant social and economic costs,” she said. [my yellow highlighting]

Aerial shot of  the Hawkesbury River in flood
IMAGE: ABC News, 21 March 2021

Tropical Cyclone Uesi predicted to cause damaging seas along Australia's east coast as it weakens

Tropical Cyclone Uesi at Category Two level, Monday 10 February 2020

The Tropical Cyclone Warning Centre Port Vila, Vanuatu, has this particular cyclone tracking south west towards south-east Qld and the NSW North Coast as it weakens.

Weatherzone reported on 10 February 2020 that:

At this stage, there is a fair bit of uncertainty around the movement of this system from Thursday onwards, with a range of plausible scenarios. 
Some forecast models suggest that Uesi will move towards the southwest on Thursday and Friday, which would allow it to move closer to Australia's east coast towards the end of the week. If this happens, the remnants of Tropical Cyclone Uesi, most likely in the form of an extra-tropical cyclone, could cause direct impacts in eastern NSW or southeast Queensland. These impacts could include large and dangerous surf, strong winds and heavy rain. It's worth pointing out that dangerous wind and rain would only occur if the system gets close enough to the coast, while powerful surf can reach Australia even if the system stays well offshore.

The Weekly Times, 11 February 2020

According to the Fiji Meteorological Service, which is tracking Uesi, its current route should take it in a south-westerly direction towards the coasts of both New South Wales and Queensland. It could enter Australian waters as early as Thursday.

The Australian Bureau of Meteorology also says there is a moderate chance the cyclone could turn southwest towards Australia on Thursday — giving odds of between 20%-50% the storm will enter the Coral Sea’s eastern region.

Issued at 2:37 am AEDT Thursday 13 February 2020. 
Refer to Tropical Cyclone Advice Number 7.

ABC News, 12 February 2020:

Tropical Cyclone Uesi could cause more havoc across the NSW coastline later this week, bringing swells of up to 5 metres. 

The news comes as the clean-up continues after the weekend's wild weather. 

The category three cyclone, which is passing north-east of New Caledonia, will track south-west towards the Tasman Sea and could cause increased swells, wind and rainfall as early as Thursday. 

ABC News weather journalist Graham Creed said the cyclone was expected to come closest to the coast on Friday and Saturday. 

"This may produce large swells, which combined with king tides may cause issues for beach erosion, as well as prolong the potential for locally heavy rainfall in showers and thunderstorms," he said....

The forecast at this stage is for swells of about 2 to 3 metres starting on the north NSW coast on Thursday and increasing to 3 to 5 metres on Friday....

By 8pm this evening, Thursday 13 February Cyclone Uesi will have dropped to a tropical low (while possibly maintaining an intensity equivilant to a Category 2 tropical cyclone) and is expected to sit less than 600km to the east of Tweed Heads as the crow flies.

At 2am Friday 14 February 2020 the tropical low is expected to be sitting further south less than 600km to the east of Moonee Beach.

Late Friday night the low will continue to track south before veering further away from the NSW coastline on Saturday.

SEE BOM ADVICE FOR UPDATES AT 
http://www.bom.gov.au/products/IDQ65231.shtml

*Image from Weatherzone, tracking map from the Australian Bureau of Meteorology & animated satellite image from NOAA Environmental Visualization Laboratory

Labor Leader Anthony Albanese has written to Prime Minister Scott Morrison proposing he convene an emergency Council of Australian Governments meeting to examine Australia's preparedness for natural disasters given the November bushfires killed four people and destroyed hundreds of homes

The Australian, 25 November 2019, p.4:

Anthony Albanese has written to Scott Morrison proposing he convene an emergency Council of Australian Governments meeting to examine Australia’s preparedness for natural disasters given the bushfires that killed four people and destroyed hundreds of homes.

The Opposition Leader has requested that the meeting addresses issues including an action plan for climate change adaptation and greater investment in research on natural disaster response, recovery and mitigation.

Other issues flagged for debate include the development of a new national strategy for disaster preparedness, adequate funding for emergency services and national park services, an expansion of the capacity of Australia’s National Aerial Firefighting Centre as well as better measures to attract and retain volunteers.

Mr Albanese said the response needed to be led by the federal government and argued the effects of climate change meant Australia was now in “uncharted territory.” “Emergency leaders, including former fire chiefs, are telling us the scale of these bushfires is unprecedented. The fire season is starting earlier and finishing later, and emergency leaders agree that extreme weather events in Australia will only increase in severity and frequency, due to climate change,” Mr Albanese said.

“In my view, these circumstances require us, as leaders, to re-examine our nation’s preparedness for natural disasters. To facilitate that, I request that you call an urgent Council of Australian Governments (COAG) meeting, including state and local government leaders to firm up Australia’s natural disaster preparedness.” Mr Albanese tweeted a copy of his letter saying that climate change would mean “longer and more intense bushfire seasons.”......

Remember to include pets in your disaster evacuation plan

The Daily Examiner, 19 November 2019: 

With 99 per cent of NSW officially in drought and 53 per cent, including the Clarence Valley, in high fire danger, residents getting ready to evacuate need to remember to include pets in their disaster plan. 

Bushfires, floods and tropical cyclones are an increasing reality around the country. 

World Animal Protection is encouraging people to be prepared by planning ahead – and have disaster packs for cats, dogs, horses, birds and small animals available to help. 

“Many people don’t have a disaster plan that includes their pets,” World Animal Protection director Simone Clarke said. 

“We know from looking at past disasters that people can make last-minute decisions to try to keep their pets safe, putting themselves in danger in the process. 

“Pets must be part of emergency planning, not just to protect them but to keep your family safe too.” 

World Animal Protection’s top disaster preparation tips are: 

Prepare a disaster survival kit for your pet with food, water, medicine, identification and a favourite toy for comfort. 

Put it in an easy-to-access spot and check it regularly to keep it up to date 

Identify a “safe house”, such as a friend’s house, pet-friendly motel or animal shelter where you can take your pet during a disaster 

Practise your plan so your pet is used to moving into their carrier. This will ensure you and your pet can move fast and stay calm in an emergency 

Display a rescue sticker on your doors and windows to alert emergency responders that there are pets in the home that need to be rescued. 

Put your pet’s name on the sticker so emergency personnel can call out to them Update your pet’s ID so that rescuers can contact you if they find your pet in an emergency. It’s best to get your pet microchipped so it’s easy to update contact information. 

Visit www.protectyourpet.org.au to plan for your pet.