Moist NW flow and severe weather, Upper NI, 5 Dec -

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Manukau heads obs
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by Manukau heads obs »

WIATNT, you present a list of so called facts
when they are are just your opinions only
there has been ample evidence of tornado damage
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Brian Hamilton, weather enthusiast. My weather dataEmail: [email protected]
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by Weather Watcher »

I'd like to support WIATNT. Personally, I think he's the only one in this thread looking at it rationally and making any sense.
WIATNT
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by WIATNT »

If you go here you can see historic maps (via drop downs look for historic photographs)
http://maps.aucklandcouncil.govt.nz/auc ... cilviewer/

Note that a large group of trees were removed where the eastern onramp at squadron interchange is. The trees left were old spindly... tall and thin, which would be very easily damaged even in moderate winds.

For the record, it's a brilliant mapping package and one can use the measuring facilities to get metres, areas, and use the spacial facility to see widths from a straight line.

The width of damage in wallingford is about 500m... not tens of metres as caused by tornado damage I've seen written. Not even 100m... but just on 500m!!! That suggests strong gales to me... especially given the direction of damage appears to be the same both sides.
jamie
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by jamie »

I think its fair to say we will always have our own opinion regarding what caused the damage. Its fair to say we all agree straight line winds. Some think a tornado was included others dont. People are allowed to have their opinion and as yet no one is proved right or wrong and i dont think we will ever find out.

However i think 95% of us in this discussion agree on that Metservice badly missed the boat on this storm. Assuming there was no tornado (which they claim is impossible to predict and i tend to agree with that) then why were they unable to forsee the bow echo with severe straight winds which would definitly has shown up on their dopplar as this was on a large scale.
spwill
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by spwill »

WIATNT, tell us about your previous experience with tornadoes, how many have you seen and please list the tornado damage events you have looked at in the last 10 years. Which suburb do you live in and what was your experience with last thursdays weather.
WIATNT
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by WIATNT »

Here's a spacial pic of an estimated path of the Phantom Hobsonville Tornado, 2012.

Based on limited photo/video and site visit to Hobsonville Point post damage.

The width of damage around Wallingford is about 500m. The yellow bands from a projected hypothetical path (embracing Waimarie Rd , Squadron interchange and Wallingford Way) are at 50m intervals.

Does anyone have detailed damage reports so this can be mapped logically?
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Cook
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by Cook »

spwill wrote:WIATNT, tell us about your previous experience with tornadoes, how many have you seen and please list the tornado damage events you have looked at in the last 10 years. Which suburb do you live in and what was your experience with last thursdays weather.
All WAITNT is doing is presenting the facts as he sees them. You may or may not like this approach but he has my full support. Being a storm chaser does not make you an expert on anything. The person who keeps looking for tornadoes is certain to find some sooner or later and such a person may not be the most impartial observer or analyst...
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Cook
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by Cook »

WIATNT wrote:Here's a spacial pic of an estimated path of the Phantom Hobsonville Tornado, 2012.

Based on limited photo/video and site visit to Hobsonville Point post damage.

The width of damage around Wallingford is about 500m. The yellow bands from a projected hypothetical path (embracing Waimarie Rd , Squadron interchange and Wallingford Way) are at 50m intervals.

Does anyone have detailed damage reports so this can be mapped logically?
Thank you again. You would think that out of the all the smartphones that everyone carries around these days at least one would have captured a picture of this "tornado" if it was in fact a tornado that generated a damage path that wide.

You could subscribe to the notion that has been presented in this thread that the "tornado" was seen by many people but it was invisible because it was shrouded by rain. I wonder how they saw something that was invisible. Oh yes, the media says it was a tornado so that is what they must have seen!
spwill
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by spwill »

WIATNT has made 15 posts in less than one day dismissing other opionions, what is your experience with tornadoes, how many previous tornado events have you surveyed ? please give us a list.
spwill
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by spwill »

Cook, interested to know what is your experience with tornadoes ? , how many have you seen and which tornado damage events have you surveyed in the last 10 years ?


My experience suggests a tornado event here.
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Cook
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by Cook »

spwill wrote:Cook, interested to know what is your experience with tornadoes ? , how many have you seen and which tornado damage events have you surveyed in the last 10 years ?


My experience suggests a tornado event here.
I could give you my CV, but I am not applying for a job so I won't. If you feel the need to play the man rather than the ball I can tell you right now that I do not play that game. I am only interested in the facts surrounding this event.

What I can tell you is that I never saw an invisible tornado.
WIATNT
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by WIATNT »

NZstorm wrote:Have the armchair experts asserting there was no tornado been over and done a survey on the ground?
Yes. Several times...

Have you?

I'd read about the tornado, but not seen any video of it. I know the area well both work wise and recreational wise. I know nearly all of the houses damages were in the process of being removed any way. When I worked out the width of the damage I wondered how such a large tornado could escape the purview of the ubiquitous cell phone video camera. The videos I saw showed extreme gales/gust, not a twister with updrafts. So I went and look and started my research.

I asked several experts... they weren't sure. One said;

"The biggest sticking point for me is the damage - the damage shows winds were closer to 200km/h. Downdrafts just don't produce gusts like that - squalls, which is what MS seem to be calling this, are short and sharp so
similar - but they tend to continue in a line across the city. They also are usually accompanied by other damaging gusts nearby or region wide. They also don't produce - that I know of - winds in excess of 200km/h. That needs to be caused by all of that energy focused in one spot...

If this wasn't a tornado this was probably NZ's biggest squal on record....

I think the damage was just too intense for it to be a gust of wind - ...im not 100% sure it was a tornado
- but I'd say I'm 90% sure..."

Winds of 150km were recorded at Snapper Rock... a suburb away. 110kph was recorded at Whenuapai... out of ground zero.

Freak storms do occur. This one may have had a tornado associated with it but it is clear the bulk of the carnage was not caused by one.

My intrigue is that there are three threads in this discussion.

1. MS never put out a severe storm warning.
2. MS are old school and protective of their patch and should make their sat info available for everyone.
3. The storm was/was not a tornado.

Risk management is about credibility. Claiming something was a tornado when it is obvious that most, if not all, damage was not caused by a tornado destroys credibility.

If one said that the damage has all the hallmarks of tornado damage, and it is puzzling that there is no video or picture evidence of something that happened in broad daylight with, to quote the Prime Minister, hundreds of workers on site, can not provide anyone with a great deal of certainty.

I asked several people who were there... they said it was a tornado. When asked if they saw a tornado, they said no, but people are saying it was so it is.

Analysts need to look beyond the surface. Am I a stormchaser? Nah. I'm someone who makes a living from analysing information to sort the wheat from the chaff. One doesn't need to stick one's head in the dunny to know that it stinks.

If one referred to the violent storm that swept through the NW that would be accurate. To claim it was a tornado based on conjecture is..., well, it's conjecture.

Set up a timeline... post all media reports/vieos/pictures in order. Get a map and pin all the damage to document its path. Mark which way fallen trees are lying... Mark recorded wind speeds... 110kph and 150kph some 4 km apart are not consistent with a tornado.

There MAY have been a tornado, but if it was invisible because it was raining, how would people know it was one? Especially when their was no reported vortex/cyclonic movement... just swirling gales.

Anyways, I'm done. Just remember, where you find two weather experts you'll find three forecasts. 8)
WIATNT
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by WIATNT »

ps... and I never said there wasn't a tournado... just that if there was one no one has any photo/video evidence of one that travelled some 4km in broad daylight with hundreds of people in its path. The photo/video evidence shows extreme gales and rain... no swirling... no updraft.

Others have said because of the rain it would have been invisible. In which case, the objects would still have swirled in the vortex and been caught in the updraft.
spwill
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by spwill »

Cook wrote:]

If you feel the need to play the man rather than the ball I can tell you right now that I do not play that game. I am only interested in the facts surrounding this event.
.

No game, only asking you about your experience with tornadoes ,you are quick to dismiss this one. I have looked closely at a fair number of tornado events in NZ, visited the locations including a few in the US but I wouldn't call myself an expert :> .
Last edited by spwill on Wed 12/12/2012 14:20, edited 2 times in total.
spwill
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by spwill »

WIATNT wrote:ps... and I never said there wasn't a tournado... just that if there was one no one has any photo/video evidence of one that travelled some 4km in broad daylight with hundreds of people in its path. The photo/video evidence shows extreme gales and rain... no swirling... no updraft.

Others have said because of the rain it would have been invisible. In which case, the objects would still have swirled in the vortex and been caught in the updraft.
I think it is a mistake to think a tornado is going to always present as an obviuos funnel in the sky that people will recognise. On some of the news footage people talk of objects flying in different directions, flying one way then comming back in the opposite direction
GraemeWi
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by GraemeWi »

Image

This one was on the TVNZ website and the source credited to Christina Woods

I'm not sure of where the image was taken from or it's orientation. It looks like a screen grab (maybe from a video?) so there may be more footage.

Mind you in the hours after the event, there were pictures on either stuff or the herald that were sourced from twitter on contrails in the sky somewhere in Asia that had the hashtag tornado
WIATNT
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by WIATNT »

OK, spwill... no one has questioned tornado in Rotorua that I'm aware of... even people were picked up in the vortex and moved some distance. But for a lay person, there have been no reports of classical/obvious visual signs of a tornado at Hobsonville. It seems to be based on "it's been in print three times so it must be fact."

No recorded vortex
No recorded twister or typical updraft with debris falling from the sky.
No videos/photographs despite hundreds of people being exposed in broad daylight. Just videos of severe gusty gales and intense rain.
Damage path some 4km long and some 500m across.

How could such a large tornado out in the open in broad daylight have been so undocumented in 2012? Surely with networking/social media Metservice almost become irrelevant in the context of micro weather events.

Can I ask you a question in light of your stated expertise. Have you ever seen an invisible tornado in broad daylight?
WIATNT
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by WIATNT »

spwill wrote: I think it is a mistake to think a tornado is going to always present as an obviuos funnel in the sky that people will recognise. On some of the news footage people talk of objects flying in different directions, flying one way then comming back in the opposite direction
If it wasn't an obvious funnell in the sky that people recognise, then on what basis was it reported as a tornado? Surely the typical twister is the point of reference for mere mortals???

It is commonplace for gusts of wind to surge back and forth in storms... even gales. In gales these surges can be due, in part, to pressure differences on the leeward side of ojjects such as buildings. I would have thought it was less likely in tornados where the wind momentum is rotational and unidirectional.
WIATNT
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by WIATNT »

GraemeWi wrote:
This one was on the TVNZ website and the source credited to Christina Woods

I'm not sure of where the image was taken from or it's orientation. It looks like a screen grab (maybe from a video?) so there may be more footage.

Mind you in the hours after the event, there were pictures on either stuff or the herald that were sourced from twitter on contrails in the sky somewhere in Asia that had the hashtag tornado
GraemeWi, I don't recognise the road or terrain. It's certainly not Hobsonville Road. Would be really interesting to try and locate the road and direction and triangulate the location of the funnell.
spwill
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by spwill »

WIATNT wrote:O.

How could such a large tornado out in the open in broad daylight have been so undocumented in 2012? Surely with networking/social media Metservice almost become irrelevant in the context of micro weather events.

?
As mentioned above , it was likely not your classic tornado that the average member of the public would recognise however one person I talked to at Hobsonville said he saw low swirling cloud which to him looked like a tornado, he called it a tornado.
Looks like MetService called it a tornado early on thursday afternoon.

My thoughts only favour tornado. I can this argument going on forever
WIATNT
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by WIATNT »

Ah, so it's a new kind of non-classical tornado based on the observation of one person you talked to at Hobsonville who said he saw "low swirling cloud which to him looked like a tornado, he called it a tornado."

MetService did call it a tornado early on thursday afternoon... based on media reports no doubt.

Spwill, Would you seriously accept "low swirling cloud which to him looked like a tornado, he called it a tornado" as scientific evidence of a tornado?

OK, so we agree it wasn't a 'classic' tornado that Joe Average would recognise.

Great, because I'm Joe Average and I haven't seen anything that I recognise as being a 'classic' tornado.

Thanks for confirming that.

I'll keep an eye out for low swirling cloud and invisible tornados in the future. Who knows, I'll be experienced and expert enough to become a weather forecaster before you know it! :-)
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NZstorm
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by NZstorm »

WIATNT wrote:Ah, so it's a new kind of non-classical tornado based on the observation of one person you talked to at Hobsonville who said he saw "low swirling cloud which to him looked like a tornado, he called it a tornado."

MetService did call it a tornado early on thursday afternoon... based on media reports no doubt.

Spwill, Would you seriously accept "low swirling cloud which to him looked like a tornado, he called it a tornado" as scientific evidence of a tornado?

OK, so we agree it wasn't a 'classic' tornado that Joe Average would recognise.

Great, because I'm Joe Average and I haven't seen anything that I recognise as being a 'classic' tornado.

Thanks for confirming that.

I'll keep an eye out for low swirling cloud and invisible tornados in the future. Who knows, I'll be experienced and expert enough to become a weather forecaster before you know it! :-)

Obviously weather and meteorology is not your topic WIATNT.
WIATNT
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by WIATNT »

Steven W, what have I missed?

We are not talking about some theoretical event. It occurred in broad daylight with hundreds if not thousands of witnesses.

You don't have to be a rocket scientist to realise that ""low swirling cloud which to him looked like a tornado, he called it a tornado" and talking of invisible tornados masked by rain and failing to explain the lack of vortex and cyclonic wind movement is woo science.

No wonder weather forecasts are so reliable... experts don't even talk the same language as Joe Average. It's called Communication 101.

We aren't discussing meteorology or even weather per se. We are discussing what hundreds, if not thousands of people saw or didn't see.

Let's try and place that picture above (Christina Woodward) The streetscape doesn't look like anything I'm familiar with out west...
WIATNT
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by WIATNT »

This is the best raw video I can find.


http://tvnz.co.nz/national-news/raw-vid ... nd-5267504

Looks straight line to me... no vortex/cyclonic wind, just intense severe gusty gale.... would rip any old gnarly tree to shreds.

How is this a tornado? Someone please take me through it frame by frame.

Joe Average.
WIATNT
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Re: Moist NW flow and severe weather, Upper NI, 5 Dec -

Unread post by WIATNT »

So the picture above of the "Hobsonville Tornado" turns out to have been taken from the Northern Motorway at the Greville Rd intersection looking over toward Rangitoto... about 10 km from Hobsonville... so it is a proven red herring/hoax.

But then we mustn't let the facts get in the way of a decent tornado story...

Critical analysis of the evidence, people!
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