"Tropical cyclone" to hit New Zealand in mid-winter

[J07]

There's a depression that formed off the tropical Queensland coast, that is currently sitting just inside the tropics off about Townsville.

It's forecast to deepen quickly, at bomb rate, and is going to take only two days to get itself square on top of the North Island.

Forecasters saying it's no ordinary winter storm, and is one of the deepest for years.

Part of what makes it interesting is the tropical origin, unusual for mid winter, and also that when it arrives here, it is forecast to still have something of a warm core. Wierd!

The low pressure centre will be in the region of 968hPa, according to the models, which might be getting over-excited, who knows!

No much doubt that we will see the strongest winds of the month from this. Easterlies at Mokohinau island or Hick's Bay I would guess, perhaps gusting up to 120mph (which would be the highest this year).

Dewpoints going to be very high also.

For July...this is all going to be a bit surreal!

edit: should not be in hurricane section sorry!

Edited July 24, 2008 by J07

[The PIT]

Eek Day after tomorrow springs to mind.

[Cookie]

keep us updated mate

[Roger J Smith]

Thanks for drawing our attention to this. My daughter is in NZ for a year working and travelling, she's in Paraparaumu north of Wellington actually, and I expect she would see some very strong east winds blowing down the slopes there, but I'm just wondering, does a circulation like this bring heavy snow to upland areas? And what would you expect might be the elevation where snowfall might begin on the North Island?

From the track of this system (I went to bom.gov.au for my guidance) I would hazard the guess that almost all of the North Island would be in strong easterly winds, only the north tip would get into the warm sector and any strong NW winds and I would have to imagine that some place around Auckland could see a lot of rain from this.

[Iceberg]

This would be big news if it were the UK.

Looking at the phase diagrams it does develop strong warm core charecteristics, however the SST profile doesn't in any way support this. A big monster with Rapid development certainly.

Is this kind of thing normal down there ?.

Edited July 25, 2008 by Iceberg

[Coast]

Latest updates and warnings here.

'Make sure you have your survival kits ready and if you live near small streams you need a plan in case it floods; that's the warning coming from the Radio Network's Weather Watch Centre tonight as a sub-tropical low continues to rapidly deepen north west of New Zealand'

'The Radio Network's Head Weather Analyst Philip Duncan says the storm is rare and nasty and poses a "significant risk" to life and property. "We're not trying to alarm people but the public in northern New Zealand need to be prepared for this major storm tomorrow. Some people will lose roofs, some will lose power, and some will be isolated by floods and slips. This storm is serious and we are expecting some damage'

[J07]

Thanks for drawing our attention to this. My daughter is in NZ for a year working and travelling, she's in Paraparaumu north of Wellington actually, and I expect she would see some very strong east winds blowing down the slopes there, but I'm just wondering, does a circulation like this bring heavy snow to upland areas? And what would you expect might be the elevation where snowfall might begin on the North Island?

From the track of this system (I went to bom.gov.au for my guidance) I would hazard the guess that almost all of the North Island would be in strong easterly winds, only the north tip would get into the warm sector and any strong NW winds and I would have to imagine that some place around Auckland could see a lot of rain from this.

I would say for the North Island she's in a pretty good location to miss the worst of this storm. Saturday evening looks the worst. It's hard to predict what the wind will do in New Zealand. Quite often it will blow perpendicular to the isobars (case in point - Westerly is the dominant wind direction in New Zealand, yet Wellington never, ever gets westerly winds. In a Westerly flow it will get Northerlies) due to lee trough and wind river issues.

If there is a favoured gorge near Pram, there could well be gales blowing down from there. Without knowing the stability profile of the air though, it's hard to judge. At a fair guess though, you'd expect gusts of over 100km/h.

For snow, I'd say that's only going to be possible above 1000m for the North Island. In brief, that means the Central Plateau is at risk, and there is likely to be dustings over the Tararua ranges, which get up to about 1600m or so- these are the hills to the east of Paraparam.

[J07]

This would be big news if it were the UK.

Looking at the phase diagrams it does develop strong warm core charecteristics, however the SST profile doesn't in any way support this. A big monster with Rapid development certainly.

Is this kind of thing normal down there ?.

Yes in order to find anything in the region of warm enough SSTs you need to go north of 20S at this time of the year!

From what I can see, the most rapid deepening will occur just northwest of NZ, as it reaches the region of the southern exit of the subtropical jet stream, perfect upper divergence there.

It is big news down here. "No ordinary storm" they are calling it. Civil defence alerts in Auckland...that doesn't happen terribly often even though somewhere up there will always get a gust in the region of 100mph at some point during winter.

In terms of "does this happen often?". Not on this scale, no.

We tend to get depressions from the tropics during cyclone season and in the winter. Of course normally they are different beasts. This year we were lucky in getting only one cyclone (!), I've attached the MSL analysis for it approaching. I've attached Funa from this year, just before going extratropical. In this case, there was a stubborn high pressure just letting go (the story of our summer). But now, we have just had a depression effect us, there is no high to our east, and so this deep low is going to move over us very quickly. There are blocking highs to our south. Between 50-60S, this is pretty odd to see. The Southern Ocean has been shut down. Normally it is the most persistent belt of depressions on the planet...no land in the way until South America. It has been like this for a while. A stubborn block for sure. I wonder if this is allowing the tropics to be ushered in more?

In winter they drop out of the subtropics, but usually are much slower, with a complex frontal system associated. They dawdle and meander their way down, giving us warm, humid grot for days! So this one is much quicker.

The place to be is the south island's west coast. Fine, light winds, high cloud. 12-14C.

For marine areas, there are "very high" seas forecast, swells of about 5m (actually less than we've seen of late) and peak winds of 50kts gusting to 65kts. You just know some idiot will be out there though!

I'd say it's a fair bet that Northland will get cut off as it usually does each winter. There's not an awful lot of roads out there. And last July their capital had no road access to the rest of the country one day.

Norfolk Island at 9:30PM local time reporting dewpoints of 19C. Very unusual for winter even in the subtropics!

Here is the official warning:

MAJOR STORM EXPECTED TO AFFECT MUCH OF THE NORTH ISLAND THIS WEEKEND

A low over the north Tasman Sea is expected to deepen rapidly overnight and approach northern New Zealand Saturday morning. This unusually intense low is forecast to move over Cape Reinga late Saturday afternoon then track southeastwards past Coromandel Peninsula around midnight, and lie near East Cape by midday Sunday. A front ahead of the low is expected to bring widespread rain to the North Island by the end of Saturday and gales are likely to affect most parts of the North Island. The heaviest rain should be in Northland, northern Auckland, Coromandel Peninsula, Gisborne and the Hawkes Bay. In these areas streams and rivers could rise quickly,with surface flooding and slips likely.East to southeast gales are also expected to affect the North Island,with potentially damaging wind gusts of around 130 km/h possible in most exposed parts of the North Island, excluding Wairarapa and Hawkes Bay. MetService advises the public that winds of this strength have the potential to damage trees, powerlines and insecure structures and make driving hazardous, especially combined with heavy rain and possible slips. Boaties are advised to make moorings secure as soon as possible as high winds and large waves are likely about northern and eastern coasts of the North Island. This is a potentially destructive and dangerous storm and people in the North Island, especially from Waikato northwards, would be well advised to avoid unnecessary travel.

Edited July 25, 2008 by J07

[rc28]

150km/h gusts recorded so far;

http://www.nzherald.co.nz/section/1/story....jectid=10523616

[J07]

From what I know at present:

Highest recorded wind gust was 100mph, surprisingly low considering the north of the country holds this year's record gust of 114mph....

Lowest air pressure was a pretty amazing 962.9hPa at Cape Reinga!

Dewpoints seemed to reach 16C but no higher.

This information is incomplete though. It might have to wait for NIWA to release all the stats to find out what really happened.

[J07]

http://www.ew.govt.nz/riverlevelsandrainfa...mp;catchment=16

Showing about 170mm in 12 hours, quite a way from their record but still a fair old bit!

[J07]

Queenstown has forecast highs of only 3C today, with 5C tomorrow, pretty darn low.

Road snowfall warnings out but nothing big.

DESERT ROAD

Snow is likely to fall on higher parts of the road from later this morning, and

may become heavy for a time this afternoon before turning to rain this evening.

10cm of wet snow is possible on higher parts of the road between 11am and 8Pm

today.

LINDIS PASS

A few snow showers are likely on higher parts of the road from late this

afternoon through to Sunday afternoon, with 1 to 2cm possible during this time.

PORTERS PASS

A few snow showers are likely on higher parts of the road from this evening

through to Sunday night, with 2 to 3cm possible during this time.

LEWIS PASS

A few snow showers are likely on higher parts of the road from the early hours

of Sunday morning through to Monday morning, with 5cm possible during this time,

mainly east of the pass.

Skiers having a time of it

http://www.metservice.com/default/index.ph...ias=coronetpeak

Hmmm, forecast highs of -6C and lows of -14C at 1645m ASL....wouldn't want to be there personally!

mms://ac1.streaming.net.nz/metservice/queenstown_ski_low.wmv

Edited July 26, 2008 by J07

[J07]

There now has been a 105mph gust. Mean speeds have also returned to above 60mph again.

Wellington faring quite well, nothing notable here at all, 42mph gusts in the city, 64mph gusts about the hilltops.

[Cookie]

how high did or has it got mate?

[J07]

how high did or has it got mate?

Not sure yet, from what I have found, 108mph seems to be the highest gust. We will find out for sure during the climate summary, probably will be released on about the 5th August or so.

Quite surprised that I've not seen anything over 114mph with this storm to be honest. Maybe I missed it.

http://www.stuff.co.nz/4631448a11.html

Apparently 10,000 skiiers went up the mountains.....dull or what!

http://www.stuff.co.nz/718016a27970.html

http://www.stuff.co.nz/4632915a11.html

Why would you go out in a canoe during a storm like that?

[Cookie]

thanks for the updates mate

[J07]

Well these people certainly help define "die-hard"....

About 2000 skiers formed human chains as they scrambled to safety from "insane" weather as 200kmh winds battered Mt Ruapehu, sparking a 12-hour evacuation.

Turoa and Whakapapa ski-field management said they were caught out by the wild weather, but had no regrets about opening.

Ten thousand skiers were on Mt Ruapehu when the storm struck at 10.30am on Saturday, two hours earlier than forecast, in the "weather bomb" that swept much of the North Island. Most skiers got off the mountain but about 2000 "diehards" continued till the fields were closed.

Ski-field staff spent 12 hours guiding skiers down the slopes and leading cars along the mountain roads in groups of five, but 100 vehicles had to be left in the car parks overnight.

"One minute it was a beautiful, clear winter's day, then the weather was horrendous. It was unbelievable," Ruapehu Alpine Lifts spokesman Mike Smith said.

"There were a few people who were quite scared, but I don't think we made a bad decision in opening. That's a question we have asked ourselves but I don't think anyone could have predicted how quickly the weather was going to come in. It was just one of those things.

"I expected it to worsen gradually throughout the afternoon, but this came in very fast. Normally you know when a storm is coming, but there was no warning.

"One minute it was beautiful, thousands of people were having a lovely time, then bang and it was not quite so lovely. I guess nature throws up things to show you who is in charge.

"It was a pretty interesting night, very freaky, but everyone coped well. But it's not something I want to do again in a hurry."

Police said they had no problem with the ski-fields having been opened, but a snowboarder wished he had not gone up the mountain.

"The wind was unreal. I've never felt anything like it. I was really glad when I got off the mountain. There were plenty of kids up there who didn't know what was happening. It has definitely made me think twice about going up if bad weather is forecast."

Yesterday the weather had calmed down, and Mr Smith was hoping the ski-fields could reopen today.

http://www.stuff.co.nz/4633252a11.html

[Cookie]

gee wizz nutters

[J07]

Yep, looks like the max wind gust was 109mph for the country. Max for Wellington was 75mph about the hilltops.

[opplevelse]

Issued by MetService at 08:41pm 30-Jul-2008

STORM MOVING SOUTH BRINGING HEAVY RAIN TO THE EAST OF THE SOUTH ISLAND. SEVERE SOUTHEAST GALES IN BULLER AND WESTLAND SHOULD EASE OVERNIGHT, BUT NORTHERLY GALES CONTINUING OVER NORTHERN NEW ZEALAND THROUGH TO THURSDAY MORNING

A deep low west of the North Island is forecast to move slowly southwards and cross central New Zealand Thursday evening and then gradually weaken on Friday morning. The rain has eased over eastern parts of the North Island and warnings for these areas are lifted. Heavy rain should ease in Marlborough and the Richmond Ranges tonight (Wednesday), but further significant rainfalls are forecast about Canterbury until Thursday evening, with a period of heavy rain also expected in eastern Otago during Thursday. People in all these South Island areas are advised to look out for rapidly rising rivers and streams, as well as surface flooding and slips.The damaging easterly gales from Taranaki to Horowhenua have eased and the wind warnings for these areas are lifted. The severe southeast gales should ease in Nelson and Marlborough tonight and in Buller and Westland by early Thursday morning. Northerly gales are also expected over northern New Zealand through to Thursday morning,with severe gales in exposed parts of Northland, Auckland,Coromandel Peninsula and the central North Island high country. People in all these areas, especially Buller and Westland, are warned to look out for further wind damage until the severe gales abate.

MORE DETAILED INFORMATION FOR EMERGENCY MANAGERS AND TECHNICAL USERS FOLLOWS:

HEAVY RAIN WARNING

AREA/S AFFECTED: RICHMOND RANGES, EASTERN MARLBOROUGH, KAIKOURA RANGES AND COAST CANTERBURY EASTERN OTAGO FORECAST:

RICHMOND RANGES AND MARLBOROUGH, EXCLUDING THE KAIKOURA COAST Heavy rain should ease tonight. In the 2 to 3 hours from 8Pm Wednesday, another 20 to 30mm is possible about higher areas.

KAIKOURA COAST AND RANGES Heavy rain should ease during early Thursday morning. In the 10 hours from 8Pm Wednesday to 6am Thursday, another 60 to 80mm is likely about the ranges, with 40mm nearer the coast.

CANTERBURY In the 21 hours from 8Pm Wednesday to 5pm Thursday, 120 to 150mm of rain is likely about the foothills, with 40 to 60mm over the plains. Snow is expected above 700 metres at first, but the snow level should rise during Thursday.

EASTERN OTAGO NORTH OF DUNEDIN In the 15 hours from 6am to 9pm Thursday, 60 to 80mm of rain is likely about the hills and ranges, with 30 to 40mm nearer the coast.

FREEZING LEVEL: 1000 metres rising to 2000 metres during Thursday.

STRONG WIND WARNING

AREA/S AFFECTED: NELSON MARLBOROUGH BULLER WESTLAND NORTHLAND AUCKLAND COROMANDEL PENINSULA THE CENTRAL NORTH ISLAND HIGH COUNTRY FORECAST:

NELSON AND MARLBOROUGH Severe southeast gales should ease in the next few hours, but gusts of 120 km/h are possible up to 10pm tonight in exposed places.

BULLER AND WESTLAND Severe southeast gales should ease from the north overnight, but gusts of 140 km/h are likely in exposed places north of Greymouth until around midnight and further south until 3am Thursday morning.

NORTHLAND AUCKLAND COROMANDEL PENINSULA AND THE CENTRAL NORTH ISLAND HIGH COUNTRY:Northerly gales are expected until mid-morning Thursday, with locally severe gale gusts of 120 km/h in exposed places, especially near the coast and higher terrain, through to 9am Thursday morning.

WARNINGS NO LONGER IN FORCE

HEAVY RAIN WARNINGS HAVE BEEN LIFTED FOR: BAY OF PLENTY GISBORNE HAWKES BAY WAIRARAPA EASTERN WELLINGTON AND THE NORTHWEST RANGES OF NELSON NO FURTHER WARNINGS WILL BE ISSUED FOR THIS EVENT FOR THE ABOVE AREAS.

STRONG WIND WARNINGS HAVE BEEN LIFTED FOR: TARANAKI WANGANUI MANAWATU NO FURTHER WARNINGS WILL BE ISSUED FOR THIS EVENT FOR THE ABOVE AREAS.

NEXT SEVERE WEATHER WARNING WILL BE ISSUED AT OR BEFORE 9:00am Thursday 31-Jul-2008

[J07]

Yeah, this is another following hot on its heels. Bigger and slower than the "tropical cyclone" and it doesn't have a warm core either. Just a meaty monster really. And giving worse flooding to most because of saturated ground and slow speed.

And there's another depression in the wings for us after this! Only that's more of a standard low.

[J07]

LATEST: The storm which has been lashing the country over the past 24 hours is now battering the South Island, causing evacuations and flooding.

A civil emergency has been declared in Marlborough with numerous evacuations in Picton because of flooding, while the MetService has issued heavy rain warnings for the Richmond Ranges, Eastern Marlborough, the Kaikoura Ranges, Canterbury and Eastern Otago.

Twelve residents of Sefton near Rangiora have been evacuated to the local school hall.

Police say there is surface flooding on the east coast of the island from Picton to Christchurch, and the road from Blenhiem to Kaikoura is currently closed due to flooding and debris on the road.

Roads around Waimakariri area all have surface flooding right through to Christchurch, with surface flooding affecting Christchurch city roads. Roads around Amberley have been affected by surface flooding.

In Picton, police and volunteers laid sandbags yesterday to keep floodwaters out of the town centre.

Thirty people from Alexanders Holiday Park a motor camp joined at least 35 Picton residents who were forced to leave their homes to spend the night at Queen Charlotte College.

Volunteers laid sandbags around the affected houses in an attempt to prevent further damage.

The town was lashed by wind and rain yesterday. Gale-force winds were still being reported last night.

Senior Constable Russ Smith said there were concerns for emergency workers as well as residents. "At least one house had its roof torn off," he said. "It's very dangerous."

A woman drowned trying to cross a swollen Bay of Islands river yesterday. It is thought her 41-year-old male partner was also swept away.

About 25,000 Horowhenua households were without power last night after gale-force winds uprooted trees and took out power lines. Levin's city centre was largely blacked out for much of the day.

Power company repair crews were still battling in the dark last night to claw back control of their electricity network, 17 hours after the power went out.

Electra network chief executive John Yeoman said last night the 50 workers in his crews had most of Levin and Waitarere Beach back online, and were about to re-connect Foxton and Otaki.

Some rural properties would not be repaired until tonight, he said.

Linesmen had been working in gales all day: "Wind storms normally just move on through, but this one sat on us" he said. "It is the fiercest wind storm we've had for donkeys years".

In Nelson, a lack of water was the problem.

Ferocious wind gusts brought down trees and caused major damage to the water pipeline supplying the city.

Nelson residents have been asked to use as little water as possible in the next two or three days and to avoid flushing toilets, taking showers or using washing machines.

Savage winds hit the West Coast, particularly around Greymouth, where gusts up to 150km/h uprooted trees and ripped iron from roofs.

MetService forecasters last night warned of a high risk of flooding in parts of Canterbury already saturated by rain over the past week, and also of slips on the foothills.

Severe-weather forecaster Andy Downs said last night: "It's going to be a wet old day. The rain is going to be going strongly in the morning and it's not until evening we should see an easing trend. We're still going with that idea of up to 150mm around the foothills, and along the coast up to 60mm.

"This is a classic pattern for flooding. These sorts of numbers can lead to a lot of water and slips on the hills. There is potential there for sure for flooding," he said.

"These are only forecasts. They're not written in stone, but people need to be aware a lot of rain is going to fall and be cautious."

Severe southeast gales in Buller and Westland were expected to ease last night, but northerly gales over the north of the North Island would continue this morning.

Heavy rain was expected to ease in Marlborough and the Richmond ranges but people in eastern Otago were warned to expect heavy rain today.

MetService forecaster Richard Finnie said "the worst of the destructive stuff" was over for the North Island.

"But [today] we'll still have heavy rain in the east of the South Island and very strong north-westerlies over the northern half of the North Island."

Meanwhile, yesterday a tornado in Mt Maunganui uprooted trees and lifted roof tiles.

Five houses were evacuated. Resident Irene Elvy was hunkered down at a friend's house last night after the tornado ripped the ranchslider door from her living room, leaving the room scattered with glass. "It just went 'bang'. My whole ranchslider went."

Mini-tornadoes were also reported in Buller.

In Hawke's Bay, a beachfront home in Te Awanga was partly submerged by large waves at high tide about 3pm. The sea smashed the house's concrete seawall and sucked away the front of the house, forcing the evacuation of its two tenants.

Flooding was severe on the East Coast, Waikato and Bay of Plenty. Gisborne police evacuated a dozen people from the settlement of Mangatuna, 10 kilometres north of Tolaga Bay.

Former Wellington firefighter Syd Crawford, who evacuated residents during the storm 40 years ago that sank the Wahine, said yesterday's gales were worse.

"Wahine was over quite quickly - this has just gone on and on. It is a real swine."

He watched helplessly at his Levin home as winds up to 110kmh peeled his neighbour's roof off and ripped their hay barn apart, leaving it strewn in pieces.

In Upper Hutt, falling trees damaged houses and heavy rain caused flooding.

Some Air NZ flights were cancelled because of gale-force winds.

Nelson Airport was battered with the strongest gusts in the country - up to 120kmh - while Golden Cross, just north of Waihi, on Coromandel Peninsula, received the most rain: 261mm in the 24 hours till 7pm. The settlement of Pauanui was cut off by floodwaters last night.

Police warned last night that travel was becoming treacherous in North Canterbury, with flooding around Cheviot and Hawarden, and trees and debris being blown across roads in the area.

Flooding has also been reported around Kaikoura, and contractors were clearing roads there.

Downs said the extreme winds would ease by this morning, but it would remain windy.

[Cookie]

thanks for the updates mate sounds intense