Taranaki Tornado

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Gary Roberts
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Unread post by Gary Roberts »

NZ Thunderstorm Soc wrote:Sorry Stephen, I didn't mean that way. #-o
All forms of inclement weather have that element of tragidy associated with it. This event is important because of that.
I was speaking from this weather forums point of view :)


JohnGaul
NZTS
Yep. Imagine how much meteorological knowledge we wouldn't have now if we couldn't view material considered insensitive to any victims of a weather event!

I'm sure you didn't want to see bodyparts flying: it's just that tornadoes are fascinating, right?!
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NZstorm
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Unread post by NZstorm »

So what type of cloud produced this beast people? Supercell? I don't think so, some very active Cb
No ordinary cb Aaron. I heard Bob McDavitt on the radio suggesting wind speeds would have been between 200-300km/h. The cloud that produced the tornado would have been a form of supercell, a 'mini-supercell'. Called 'mini' because the cloud tops are lower than traditional supercells, not because the cb is weak.

I have saved the upper wind data from New Plymouth and soundings from NZPP and NZWP for further analysis.
Manukau heads obs
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Unread post by Manukau heads obs »

re pressure drop in a tornado
I did some searching on the web
and found this statement:
The characteristic feature of the tornado is the funnel-shaped cloud that hangs from the sky and moves around like the trunk of an

elephant. The destructive capability of the tornado is the result of an extremely sudden pressure drop of roughly 0.1 atmosphere between the inside and outside of the funnel. Winds can range in speed from 100 to 330 m/sec.
Without question, the most concentrated and powerful manifestations of atmospheric electricity
from:
http://www.project1947.com/shg/condon/s6chap07.html

air pressure is actual very powerful
i.e take a Milk tanker: they clean they inside will hot soapy water...but if no valves are open, then as it cools, it can then get crushed...like it was an aluminium can!...this has happened!
anyway, just my 2 cents worth
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Brian Hamilton, weather enthusiast. My weather dataEmail: [email protected]
Thunder
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Unread post by Thunder »

That reminds me of doing science experiments at high school. I can't exactly remember what we did but it had something to do with soft drink cans, we then boiled a small amount of water in them (I think) and then turned them upside down really quickly (so the hot water didn't fall out the top where the tab used to be) into cold water. The cans get crushed and impload really quickly, it's quite cool to watch!

So it looks like it could be a factor with tornadoes and destruction etc.

Thanks Steven Re the type of cloud it was. I didn't think it could've been a supercell becasue, well....you don't think they'll happen much if at all. I guess I've got to be open to the idea that they will happen and it's not a one in 10 year sort of thing. This is all good for us weather loving people though!

Also, I know how to see the NZPP and NZWP soundings but how did you get the New Plymouth sounding? I see on the metservice website they have this little flash (the plugin) thing that tells you where soundings occur in NZ, it even has one in Chch yet they don't show the results of it freely on the web (from what I know). And yes it shows an area in New Plymouth that does soudings, how to get this info is the question!!

Help?
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Aaron Wilkinson
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NZstorm
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Unread post by NZstorm »

re pressure drop in a tornado
I stand corrected here.

how did you get the New Plymouth sounding?
Met serivce web site, under upper air observations. They have a number of wind stations there including one from Canterbury, station 93769, which I don't know. Its not Christchurch. :)
Thunder
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Unread post by Thunder »

Ah yes, that part of the Metservice site. I forgot about that. :oops:

Still, how on earth do you decode it. I know it's got little information sheet there on how to read it etc but it's still over my head. Would be great to know so I could know Chch conditions. I wounder why the metvuw site doesn't just replicate what they do for Paraparaumu (sp?) / Whenuapie (sp?) etc for the Canterbury sounding, all soundings for that matter!
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Aaron Wilkinson
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TonyT
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Unread post by TonyT »

I think (but may be wrong) that site is the Rakaia radar.
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NZstorm
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Unread post by NZstorm »

re wind code.

I just look at PPBB

90012 surface wind( Direction/knots), 1000ft wind, 2000ft wind

90345 3000ft wind ......

All heights in feet
Direction True 3digits
Speed Knots 2 digits


Station code 93 denotes New Zealand

Each station has a 3 digit code

New Plymouth is 93308
Hokitika 93614 .............
jeffsweather
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Unread post by jeffsweather »

I was reading a story in the Daily News about another tornado fatality in Taranaki on April 22, 1973.

From the story
"When it hit the house, I could feel the floorboards lifting. It was like lying on a piano keyboard and they were all playing at once. I can't remember a thing after that, but it was horrific."

Here is the link
http://www.stuff.co.nz/stuff/dailynews/ ... 54,00.html