Damaging winds 4/10/2015

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tich
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Re: Damaging winds 4/10/2015

Unread post by tich »

But will these severe gales reach Chch? Sometimes, thankfully we miss out when damaging norwesters batter the inland plains and foothills.
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Re: Damaging winds 4/10/2015

Unread post by David »

Manukau heads obs wrote:actually wind strength is a square function due to F=MA2
and so at that speed, 10 kmh increase in windspeed is alot more damaging that just that 10kmh speed
Wrong formula though, F = ma is one of the laws of motion.
But indeed the wind pressure acting on an object is proportional to the square of the wind speed. See http://projects.knmi.nl/hydra/faq/press.html
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Re: Damaging winds 4/10/2015

Unread post by Manukau heads obs »

what I was getting at , is that accelaration, in the formula, F=MA, is a square function, as you have pointed out
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Re: Damaging winds 4/10/2015

Unread post by NZstorm »

Those cb's along coastal Southland tomorrow could pack a real wind punch given 850mb winds are progged to be 70knots.
We don't often see such strong winds in association with convection in NZ. Southland is well acclimatised to strong wind though.
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Re: Damaging winds 4/10/2015

Unread post by cantygal »

This update has it back at 160 this arvo...

AREA/S AFFECTED: CANTERBURY
FORECAST:
Severe northwest gales gusting 160 km/h or possibly more in exposed
places and especially the High Country, from around midday Sunday
until Sunday night.
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Richard
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Re: Damaging winds 4/10/2015

Unread post by Richard »

tich wrote:But will these severe gales reach Chch? Sometimes, thankfully we miss out when damaging norwesters batter the inland plains and foothills.
I think when we get NW wind flows as strong as this one, often the coastal areas get hit as much as inland, but they can still be hit&miss, take the Sep last years blow, from Culverden to Waikari and out to the coast didnt get much damage but either side did.
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Re: Damaging winds 4/10/2015

Unread post by Storm Struck »

Judging by the NW angle and the general topographical effect of the high country/southern alps inconjunction with previous strong NW systems,the worst areas hit should be north canterbury especially higher up but also along the coastline.
Maybe touching 120kmh there on the coast and 130+ inland, 90-100kmh through the city for a brief spell.
But its very hard to tell with these systems one shift in isobars and it goes nuts out east as well.
Canterbury, home of good rugby and severe storms
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Unread post by melja »

Still calm and warm in this part of the MacKenzie country.
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Re: Damaging winds 4/10/2015

Unread post by NZ Thunderstorm Soc »

No mention of damaging winds on MetService's short forecast for Canterbury tomorrow?

....anyway, don't want them, no more trees down please (got enough firewood here) and the chook-house better not roll as we have some baby chicks in it. Also I don't want my Stevenson's Screen to take another battering again, THANK YOU :-$ . >_< #-o
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Unread post by melja »

Wind here now and sky looks very dusty up Mt cook way, very warm wind too for this time of year.
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Re: Damaging winds 4/10/2015

Unread post by Captain Salty »

Dunedin currently 22, Kaikoura 12 and apparently sunny.
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Unread post by melja »

24C in Twizel according to MS and 25 here at the lake, wind really getting wound up now.
25C in Oamaru now.
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Re: Damaging winds 4/10/2015

Unread post by Richard »

NZ Thunderstorm Soc wrote: Also I don't want my Stevenson's Screen to take another battering again, THANK YOU :-$ . >_< #-o
I reckon your Stevenson's Screen deserves some kind of resurrection John ...hey ...maybe we could organize a few afternoon brews after sticking her up on some fence posts.
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Re: Damaging winds 4/10/2015

Unread post by MoorfNZ »

Windy here - regular nor'wester windy
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Re: Damaging winds 4/10/2015

Unread post by Razor »

Had a thoroughly wonderful day tramping around the hills above Castle Hill Village today. Magic day, no drama with winds arriving so far. Was starting to pick up a bit though across the plains as we came home around 6pm
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Re: Damaging winds 4/10/2015

Unread post by Storm Struck »

Its mild out now 15c with a breezy NW, its 8c at christchurch airport so NW hasn't made it there yet.
Its been a keen NE this afternoon ahead of the incoming NW, but not the bitter Easterly of a week ago.
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Re: Damaging winds 4/10/2015

Unread post by Richard »

Wind is not as strong now as it was during the night when there was some very big gusts.
Last edited by Richard on Sun 04/10/2015 08:31, edited 1 time in total.
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Unread post by melja »

Calm most of the night down here, very warm still and a light breeze now.
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Unread post by 03Stormchaser »

MS saying 120km for chch. Might head up port hills later on
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Re:

Unread post by Growler »

03Stormchaser wrote:MS saying 120km for chch. Might head up port hills later on

Take a stunt kite!
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Re: Re:

Unread post by Razor »

Growler wrote:
03Stormchaser wrote:MS saying 120km for chch. Might head up port hills later on

Take a stunt kite!
I'll be up there for a run
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Re: Re:

Unread post by shovelopikis »


I'll be up there for a run
You'll be up there for a fly!
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Re: Damaging winds 4/10/2015

Unread post by Dean. »

Gusts to 102k in Gore
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Re: Damaging winds 4/10/2015

Unread post by Manukau heads obs »

the Wairarapa, e.g Castle Point/Cape Turnagain, is the windiest place currently ..gusts to 70knots (145kmh)
(not unusual for those places...its a 'pressure release valve' there)
Parts of Otago been getting gusts to 45kts
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Re: Damaging winds 4/10/2015

Unread post by Orion »

Breeze has picked up noticeably here in the past twenty minutes. Now a noise of wind in the eaves or somewhere.
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