A month's rain has fallen in just a few hours in some areas while "giant" gold ball sized hailstones have rocked towns as a 'perfect super cell storm' makes its way across New South Wales and southeast Queensland.
The Bureau of Meteorology (BoM) has issued a severe thunderstorm warning as heavy rain, large hail stones and wind gusts of up to 125 kilometres per hour lash parts of northern and central NSW.
At 6pm the Bureau reiterated it's warning that dangerous conditions could eventuate, only an hour after saying the threat of storms had "temporarily eased".
However, Sydney, Wollongong and the Central Coast appeared to have been spared the worst of the weather with severe thunderstorms no longer expected - at least for Monday night. Southern Queensland could also be in the firing line.The weather itself didn't heed the temporary reprieve with a severe storm hitting west of Penrith, in Sydney's west, about 5pm. That storm then headed over the Blue Mountains with heavy rain and hailstones pummelling Katoomba and Blackheath. Moore, in the state's north could see "giant hail", the bureau warned. While the Central West city of Dubbo has been battered by hailstones.
In the Central Coast, electricity provider Ausgrid said 3000 homes were without power.
The BoM has predicted the worst-hit locations will be in the central and northern areas of the state. A severe warning has been issued for Tenterfield, Dubbo, Tabulam, Drake, Baryulgil and Narromine.
Dubbo is already feeling the brunt of the storm, with heavy rain, large hailstones, and flash flooding already occurring in some areas.
The Central West city has exceeded it's entire average March rainfall since 9am Monday.
NSW SES spokesman Phil Campbell says emergency services are "quite concerned" about the supercell thunderstorms.
"We're asking people up in that northeast part of the state and also inland around Tamworth and Moree just to make sure they're well prepared," he told AAP on Monday.
"At the moment, we've not had any calls for assistance, which is good news. "We do have a number of weather models, according to the bureau, that are forecasting very heavy rain from the middle to late part of the week. We're just keeping an eye on that."
Many streets within the town have been converted to shallow canals, with water lapping the gutters, and residents reporting hailstones the size of golf balls, particularly in the city's east, the ABC reported.
Extra emergency crews have been called into Dubbo and the State Emergency Service (SES) says it has so far received 25 call-outs for help.
Other location that might be affected include Armidale, Orange, Mudgee, Gulgong, Tamworth, Gunnedah, Moree, Narrabri, Walgett, Dubbo, Parkes and Lightning Ridge, according to the bureau.
And if you're living in New South Wales and Queensland you can also expect heavy rain, huge hail and flash flooding as "perfect storm" conditions are set to batter both states this week.
A low pressure trough has started to move east into New South Wales this afternoon, and looks set to collide with a second trough, causing heavy rainfall and hail.
The systems are combining to create the "perfect super cell storm" conditions which are set to unleash across large parts of Australia's east coast and further inland.
Meteorologists said there was also a chance the super cells could spawn tornadoes, however they stressed the possibility of this occurring remained low.
Sky News Weather metrologist Tom Saunders said it was possible tornadoes could form in areas such as inland NSW with strong winds supporting them developing.
"It remains in the realms of possibility," he said.
"These super cell storms are the most dangerous type. "
Sky News Weather meteorologist Tristan Meyers said Sydney was likely to escape the brunt of the storms - at least for today, but plenty of rain remained on the cards.
He warned the city and the greater Sydney area can expect to cop an absolute drenching tomorrow.
Sydney is already feeling the effects of the wild weather, and according to forecasters things are looking increasingly wet for a while.
Up to 70mm of rain is predicted to fall tonight and tomorrow, the Daily Telegraph reported.
While the severe storm warning has been cancelled for Queensland this morning, Mr Meyers said that didn't mean it couldn't develop later today with Brisbane set to cop heavy falls tomorrow and Wednesday.
"The storm warning for NSW remains in place and has the potential to bring damaging winds, and hail," Mr Meyers said.
"Unfortunately we have the perfect conditions which will bring widespread storms over large areas.
"A low and upper-pressure trough combined with a lot of cold air is creating a lot of instability and perfect conditions for hail."
Mr Meyers said the storm activity will increase in intensity and become more widespread by this afternoon across both states.
Damaging wind gusts over 90km/h and hail 2cm in diameter is also predicted with warnings for people to put cars undercover and secure loose items.
"I hope you enjoyed the nice weather over the weekend because the persistent rains are here and it looks like they're hanging around all week," he said.
New South Wales
A severe thunderstorm warning has been issued for an area stretching from Griffith in the Riverina all the way up to Moree and the Queensland border including Sydney and Wollongong.
Large hailstones, damaging winds and heavy rainfall, which could lead to flash flooding, have been predicted across the Central and North West Slopes and Plains, the Hunter, Riverina and parts of the Central, Lower Western and Northern Tablelands today.
At 5pm on Monday, the BoM said "severe thunderstorms in the warning area have temporarily eased (but) further severe thunderstorms are still possible".
The Bureau of Meteorology initially issued a warning for the northern and central parts of the state early on Monday, but the warning area was expanded before midday, AAP reported.
Numerous areas, including Tenterfield, Dubbo, Tabulam, Drake, Baryulgil and Narromine, are in the path of a low-pressure system that's moving across the state, according to BoM.
NSW SES spokesman Phil Campbell said emergency services are "quite concerned" about the supercell thunderstorms.
Mr Meyers said most of the storm's fury today would stay west of the Great Dividing Range but meteorologists were continuing to keep an eye on Sydney.
The CBD and western suburbs will see showers each day this week, with heavy falls predicted tomorrow likely to lead to flash flooding.
"Even moderate falls will bring a massive impact in Sydney," he said.
He said severe falls would hit Sydney tomorrow with up to 50mm expected across large parts of the basin.
The city can expect cloudy conditions and a top of 27C today and possible storms.
Heavy falls are predicted for tomorrow with a top of 26C and further showers and 26C on Wednesday.
The Northeast of the United States is bracing for winter's last hurrah - a blizzard expected to sweep the New York region starting today with possibly the season's biggest snowstorm dumping up to 50cm on Central Park.
The National Weather Service issued a blizzard watch yesterday for coastal regions including New York City and surrounding areas of Long Island, Westchester County and Connecticut.
A winter storm watch was in effect for a larger area of the Northeast: New Jersey, Pennsylvania and New England.
In New York City, forecasters said the first snow is expected late Monday or just after midnight Tuesday, with up to 10cm falling by dawn. Heavy snow the rest of the day could pile 25cm to 36cm more of white stuff, with sustained winds of about 48km and wind gusts of up to 80.5km.
"This would certainly be the biggest snowstorm of the 2017 winter season in New York City," said Faye Barthold, a weather service meteorologist based on Long Island.
New York Governor Andrew Cuomo said yesterday that the New York State Emergency Operations Centre will be activated Monday evening, with stockpiles of sandbags, generators and pumps at the ready, as well as snow-removal vehicles and salt spreaders.On Long Island, a snowfall of 30cm to 46cm was forecast along with equally strong winds and visibility of 400m or less.
The New York City Department of Sanitation is taking similar action and also notifying additional workers to supplement staff if needed.
Other areas, including the lower Hudson Valley and northeastern New Jersey, also could get 30cm to 46cm of snow. But those areas were not under a blizzard watch because high winds and low visibility were not expected.
The severe weather would arrive just a week after the region saw temperatures climb to between 15C-20C. Sunny days and T-shirt-wearing temperatures made it seem like winter had made an early exit. But the chilly weather and snow some areas got Friday may prove to be just a teaser.
Footage inside the Royal Caribbean cruise ship that ran into high winds and rough seas in the Atlantic Ocean last year has emerged.
The terrifying video shows a passenger looking out the window as 9m waves submerged the ship during the hurricane force storm.
The ship, carrying more than 4500 guests and 1600 crew members, was heading to Port Canaveral in Florida but was forced to turn back and return to New Jersey due to the rough weather.
It forced frightened passengers into their cabins overnight as their belongings flew about, waves rose as high as 9 metres, and winds howled outside.
His friend says: "Jesus Christ man. We're underwater, under the third floor."In the video that surfaced on Reddit, a passenger is seen leaning against the window saying, "we're just staying in one place, hoping not to die."
Four passengers were injured in the storm and the ship was damaged in some of its public areas.
Hurricane-like conditions caused items inside the ship to fly off shelves and smash into one another as the vessel leaned at least 45 degrees off centre in the swells.
The cruise line provided a full refund to passengers, as well as a discount for a future cruise.
The trip was originally supposed to be a week-long round-trip from New Jersey to Florida and the Bahamas, but the hurricane-force storm cut the holiday short.
The National Weather Service's Ocean Prediction Centre had issued an alert for a strong storm four days in advance and questions were raised as to why the cruise ship travelled through the treacherous conditions.
Royal Caribbean said the ship experienced "extreme wind and sea conditions" that were not expected.
However, it apologised to passengers following the February 7 2016 incident, saying "we have to do better".
But in September that year, Anthem of the Seas was caught up in another extreme storm.
Terrifying footage showed the 1,100ft-long Anthem of the Seas undulating through huge swells and 145km/h winds en route to Bermuda as it encountered the tropical storm Hermine.
A Scottish Power spokesman said: "We're starting to see some faults in small pockets of Gwynedd and north Wales."
Several bridges have been closed causing travel nightmares for commuters today, including the busy QEII crossing in Kent and the Britannia Bridge which links Anglesey to mainland Wales.
Met Office meteorologist Mark Wilson said: "Winds are really starting to pick up now, mainly across western parts of the country."
Aer Lingus cancelled 12 flights between the UK and the Republic of Ireland in anticipation of the winds while 36 flights out of London Heathrow were cancelled and another five at London City with other delays possible.
Strong winds forecast today are expected to cause some delays and cancellations. Please check your flight status: https://t.co/zOqJyQR48T
A Heathrow spokesman said: "Strong winds and poor weather across the UK have resulted in approximately a 10 per cent reduction to Heathrow's flight schedule.
"With Heathrow operating at more than 99 per cent capacity, there are no gaps in the schedule that can be used for delayed flights and as a result, some passengers may experience disruption to their journeys today."
Particularly at risk are high-sided vehicles, caravans and motorbikes and drivers are "strongly advised" to avoid travelling on some stretches of road in Yorkshire, the Midlands, and the East and North West.
Richard Leonard, head of road safety at Highways England, said: "We're expecting Storm Doris to have a significant impact on the roads throughout the day so are urging drivers to consider changing their plans if necessary and to slow down in stormy weather.
Meanwhile, up to 15cm of snow could fall across parts of Scotland and north-east England in treacherous, blizzard-like conditions.
Weather warnings have been upgraded to amber across Scotland's central belt, the Borders, Dumfries and Galloway, Tayside and Fife.
"We have got a fairly active area of low pressure coming in from the Atlantic," said Met Office forecaster Emma Sharples.
"It is strengthening as it moves eastwards to the UK."
The Met Office's amber weather warning alerts people that "whilst the strongest winds look to be only short-lived, damage to structures, interruptions to power supplies and widespread disruption to travel networks are likely, with a danger of injury from flying debris".
Storm Doris is expected to move on quickly, with the worst of the weather gone by Thursday evening.
While further Atlantic gusts will bring more rain and wind through the weekend and into next week, they are not expected to reach the heights of Doris.
AA spokesman John Snowling said: "The unpleasant combination of torrential rain, severe gales and heavy snow will create some very poor driving conditions, with the potential for roads to be affected by black ice, debris or standing water.
"Wind can also bring down tree branches, blow you off course or blow other vehicles into your path.
"Expect travel disruption as some roads will be treacherous."
Anyone affected by power cuts during the storm is encouraged to dial 105 for further information.
Storm Doris's appearance contrasts with Monday's temperatures, where visitors to Kew Gardens, west London, enjoyed the warmest day of the winter so far, at 18.3C (64.9F).
Parts of London and the South had temperatures warmer than Ibiza, southern Spain and Menorca.
Storm Doris: The expert analysis
Dr Steven Godby, an expert on natural hazards at Nottingham Trent University, said: "The last storm comparable to Doris caused widespread disruption across the country on January 3, 2012, with the worst affected area being the central belt of Scotland where winds gusted at well over 80mph.
"That storm tracked across the north of Scotland, but the centre of Doris is passing over the north of England, bringing its core of strong winds further south to affect the Midlands across to the Wash.
"These areas are under an amber (be prepared) warning from the Met Office with gales of 50-60 mph widely and gusts of 80mph+ possible.
"These wind speeds bring the risk of structural damage to property, falling trees and branches, interruptions to power supplies and dangerous driving conditions with restrictions on bridges to high-sided vehicles likely. "Heavy snow will also be a hazard in southern Scotland and parts of northern England for a time as well.
"People should listen to the latest forecast and follow the advice being issued by the authorities, particularly before they travel - the reason these types of storms are now named by the Met Office is to help make warnings more effective."