Cold trough crosses North Island 5-6th November

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treetop
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Re: Cold trough crosses North Island 5-6th November

Unread post by treetop »

Much better today !Good to see some punch in those cb"s. Light southerly for BOP and cold upper pool/surface heating sparked off 2 good storms Tauranga/Mt Maunganui. Both storms delivered 75 mm hail in narrow bands only.Hail pea sized but found a couple of 15 mm,Drove through the 2nd storm, traffic to a standstill for a few minutes. Quite electrically active two, overhead up to 20+ flashes per minute [so a lot of constant crackling] .As it moved off the coast it realy powered up with some good pulsing cg"s and one clear air that just missed a container ship about 3 ks out from the side of the storm What chasers would call a real angry b...ch.Papamoa road can be great for storm chasing either with Southerly storms, or NE systems ass with lows sitting off Auckland. Best day[afternoon] for me for a few years. I would guess the hail offshore may have been 20mm or so, fortunatly away from the Kiwifruit orchards. Missed the action in Whakatane in April so cant compare.Must have heard the same rumble yesterday Tgsnoopy[only 1 at about 4 30
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tgsnoopy
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Re: Cold trough crosses North Island 5-6th November

Unread post by tgsnoopy »

Sadly I was back in Hamilton and missed all the action :(
treetop
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Re: Cold trough crosses North Island 5-6th November

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LuckilyI had an afternoon off. The joys of being self employed. Must get a good camera and learn to send pics, very bad form on my part.
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treetop
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Re: Cold trough crosses North Island 5-6th November

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As the sun lit up the back of the storm I could see a large white flat island about 2 ks away. I can only assume this was a large mass of floating hail ? Quite odd, not seen this before, does anyone have an opinion? or seen this ? Its true that icebergs and fresh water float, Therefore the surface water must have been cooled enough for the hail to melt slower then the amount falling ? ????? The only other reason would be the hail splash ????? Like spouts and falling fish this rates as a very bizzar one !!!!
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Re: Cold trough crosses North Island 5-6th November

Unread post by Manukau heads obs »

that would be alot of hail to have that effect, but then the hail showers last few days have been big producers
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NZstorm
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Re: Cold trough crosses North Island 5-6th November

Unread post by NZstorm »

Thanks for the report treetop, glad somewhere got something off this set up!

Could well have been severe hail offshore.

I see another polar system next week looking fairly similar to the one we just had. Starts off in the South Island and finishes in the BOP!
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Re: Cold trough crosses North Island 5-6th November

Unread post by Manukau heads obs »

the image Tim posted does support large hail offshore
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treetop
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Re: Cold trough crosses North Island 5-6th November

Unread post by treetop »

there were reports of spouts as well. I missed the first storm, but saw nothing on the second, just the usual rotation in the RFB at the rear end [no funnel]
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Re: Cold trough crosses North Island 5-6th November

Unread post by NZstorm »

One issue with cold pools is the upper winds often drop out of them and you end up with no shear. In todays instance there was a bit of flow aloft in the BOP, about 25kts, marginal for severe hail.
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Re: Cold trough crosses North Island 5-6th November

Unread post by Tornado Tim »

I am surprised that Metservice didnt issue anything on that storm, even though the core was over the Sea, it still needed one as it was a hazard to shipping.
But then again, I am basing that judgement on 1 product alone, I could only see a Composite Reflectivity Image and not base Reflectivity nor DP Products.
Composite Reflectivity Products will always pick the max echo for each POI, so the echo shown isnt always what you get at the SFC.

I would love to see a vertical Cross section of that storm. Paul, John et all at Metservice could please post one. :)
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Re: Cold trough crosses North Island 5-6th November

Unread post by NZstorm »

Hail photos here from Papamoa storm today.

Is there a funnel in bottom pic.

http://tvnz.co.nz/national-news/your-ph ... nd-6124679
treetop
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Re: Cold trough crosses North Island 5-6th November

Unread post by treetop »

I think all the land based storms up to then were week and not warranting a warning.Any convection during the morning just looked like a repeat of yesterday. Things only got fired up after 2pm. The storm in question and others around actually collapsed very quickly after the show .
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Re: Cold trough crosses North Island 5-6th November

Unread post by Manukau heads obs »

lots of things on the dash board are reflected in the window...so hard to tell if that or a funnel
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Re: Cold trough crosses North Island 5-6th November

Unread post by tgsnoopy »

Agreed, I think it's a reflection.
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Re: Cold trough crosses North Island 5-6th November

Unread post by treetop »

same setup next thursday, long way off though fingers crossed
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