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High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Thu 27/11/2014 17:51
by NZ Thunderstorm Soc
Judging by last WE, Saturday's MetService Thunderstorm and Severe Thunderstorm warning for the province, I think there will be a high risk of thunderstorm development, tomorrow, also a moderate to high risk of severe thunderstorm development with clustered hail up to 20 cm in diameter?
EDIT: sorry being a bit cynical here [-X

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Thu 27/11/2014 20:53
by Tornado Tim
Mod Note: I have just had to move 3 or 4 posts that are completely off topic.
Please do not thread Hijack.
All such posts are at risk of deletion if they are not posted in the correct thread.
Remember: The Australian Storm Chasing Thread in the Weather Abroad Forum should have been used instead.
Kind Regards,
The NZ Weather Mod Team

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Thu 27/11/2014 23:51
by petem8nz
Sorry Tim, the excitement got best of me!

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 07:11
by matttbs
Snapped this morning

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 07:33
by melja
Stunning _b

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 08:39
by 03Stormchaser
matttbs wrote:Snapped this morning
Nice Mushroom!

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 08:53
by mikestormchaser
I haven't checked models recently. But iv seen a forcast for heavy showers. And the fact its NE in chch aswel. I believe there is cold upper trough coming up today but Metservice have no risk out for us except north if here. Un sure of what to make of today.

Posted: Fri 28/11/2014 09:17
by 03Stormchaser
Hail shower thru Halswell just now

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 09:36
by Thunder
Great looking CB Matt, showers with hail developing for some parts of Chch. Hopefully a thunderstorm. Am in Chch if anything happens.

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 09:46
by Orion
Several rolls of thunder here from that black cloud to my east 0_o

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 09:50
by mikestormchaser
Im unable to chase but Metservice has put out a severe thunderstorm warning.

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 10:03
by Skywatcher
Thunder heard to the NE of here...

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 10:25
by Razor
Yep, thunder in town...and some sporadic rain/ hail

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 10:46
by Nev
For the record…
MetService - Severe Thunderstorm Warnings
MetService Severe Tstorm Warning Map - Nov 28, 9.35am.jpg
SEVERE THUNDERSTORM WARNING
TOP PRIORITY FOR IMMEDIATE BROADCAST

Issued by MetService at 09:35 am Friday 28 November 2014.
Valid until 10:22 am Friday 28 November 2014.

This warning affects people in the following local government areas:
SELWYN and ASHBURTON.

At 09:22 am, MetService weather radar detected severe thunderstorms near ASHBURTON and THE ASHBURTON RIVER MOUTH.

These severe thunderstorms are moving towards the northeast, and are expected to lie near ASHBURTON and SEAFIELD at 09:52 am and near RAKAIA, CHERTSEY, PENDARVES and DROMORE at 10:22 am.

These thunderstorms are expected to be accompanied by very heavy rain and large hail.
...
This warning is due to be updated or lifted by 10:22 am Friday 28 November 2014.
MetService - Severe Thunderstorm Watch

Valid to: 12:30pm Friday 28 Nov 2014
Issued at: 09:43am Friday 28 Nov 2014
MetService Severe Tstorm Watch Map - Nov 28, 9.43am.jpg
SEVERE THUNDERSTORM WATCH

Issued by MetService at 09:43 am Friday 28 November 2014
Valid until 12:30 pm Friday 28 November 2014
This watch affects people in the following weather forecast districts:
Christchurch
Canterbury Plains


Isolated thunderstorms are likely to affect the Canterbury Plains this morning. One severe storm has been observed. Some of these may be severe producing large hail 20mm or more in diameter and heavy rain with rainfall rates 25 to 35mm per hour.

Issued by: Erick Brenstrum

This watch will be updated by: 11:30 am Friday 28 November 2014
MetService - Severe Thunderstorm Warnings
MetService Severe Tstorm Warning Map - Nov 28, 10.24am.png
SEVERE THUNDERSTORM WARNING
TOP PRIORITY FOR IMMEDIATE BROADCAST

Issued by MetService at 10:24 am Friday 28 November 2014.
Valid until 11:07 am Friday 28 November 2014.

This warning affects people in the following local government areas:
SELWYN, WAIMAKARIRI and CHRISTCHURCH CITY.

At 10:07 am, MetService weather radar detected severe thunderstorms near CHRISTCHURCH, MCLEANS ISLAND, TEMPLETON and CHRISTCHURCH AIRPORT.

These severe thunderstorms are moving towards the eastnortheast, and are expected to lie near CHRISTCHURCH and CHRISTCHURCH AIRPORT at 10:37 am and near CHRISTCHURCH and BELFAST at 11:07 am.

These thunderstorms are expected to be accompanied by torrential rain and large hail.

This warning is due to be updated or lifted by 11:07 am Friday 28 November 2014.
MetService - Severe Thunderstorm Watch

Valid to: 12:30pm Friday 28 Nov 2014
Issued at: 10:26am Friday 28 Nov 2014
MetService Severe Tstorm Watch Map - Nov 28, 10.26am.png
SEVERE THUNDERSTORM WATCH

Issued by MetService at 10:26 am Friday 28 November 2014
Valid until 12:30 pm Friday 28 November 2014
This watch affects people in the following weather forecast districts:
Christchurch
Canterbury Plains


Isolated thunderstorms are likely to affect the Canterbury Plains this morning. One severe storm has been observed. Some of these may be severe producing large hail 20mm or more in diameter and heavy rain with rainfall rates 25 to 35mm per hour.
...
Issued by: Erick Brenstrum

This watch will be updated by: 11:30 am Friday 28 November 2014

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 11:00
by Nev
Earlier amended T-Storm Outlook to include moderate risk of Severe T-storms over Canterbury Plains…
MetService - Thunderstorm Outlook

Valid to: Midnight Friday 28 Nov 2014
Issued at: 10:17am Friday 28 Nov 2014

Amended for severe thunderstorms over Canterbury plains this morning.

An upper level cold trough moves over central New Zealand this afternoon and onto the North Island this evening, resulting in broadly unstable conditions between Waikato and Canterbury with thunderstorms possible in several areas.

In Canterbury this morning there is a moderate risk of severe thunderstorms over parts of the plains with rainfall rates 25-35mm/hr and hail possibly reaching diameters of 20mm or more.

In Buller, there is a low risk of thunderstorms into the afternoon.In the east however,onshore winds are expected to trigger heavy showers about inland parts of Marlborough and North Canterbury.Within this area,there is a moderate risk of thunderstorms forming over the inland ranges bringing locally heavy rain with rates 10-20mm/hr,and hail possibly reaching diameters of 10-20mm.

Over the North Island, an active trough is forecast to move onto Taranaki early afternoon then sweep eastwards. There is a moderate risk of thunderstorms accompanying the trough for Taranaki, Waitomo, Taumarunui and Taihape. There is also a moderate risk of thunderstorms for Bay of Plenty from about Rotorua eastwards during the afternoon and early evening. Any storms in these areas may bring heavy rain and small hail. A surrounding lower risk of isolated thunderstorms extends from South Auckland across to Gisborne and down through Hawkes Bay.

Finally, a southerly change is forecast to move through Wellington and southern Wairarapa early evening. Heavy showers and hail may accompany this change, with a moderate risk of storms for southern Wairarapa.

Elsewhere, no thunderstorms expected.
MetService Tstorm Outlook Map - Nov 28, 10.17am.png

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 11:34
by Razor
Some impressive hail accumulations on the western side of town at present. I wouldn't be lifting the warnings yet wither, looks like developments to the SW of town looming

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 11:53
by dogmelon
You can't blame Metservice for "nowcasting" in this age of instant. They do pretty well at getting the forecasts right I reckon, but many of the public don't see it that way.

There was only a little hail in Hornby, but I saw a few bits of lightning so that will do.

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 12:12
by TonyT
Thunder and hail out Amberley way, and also in Waikuku.

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 13:33
by Storm Struck
I did think last weeks risk output was abit of a joke myself, but anyway today has been a surprise.
A big convection line went up from early morning over hornby and unleashed heavy hail 5-8mm with some close bolts, maybe more to come as winds are generally light out there and still strong convection.

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 14:20
by matttbs
Is anyone following the first cell? Looks to have rebooted itself north of chch going by the radar. Interesting looking wall of rain approaching me from the south now, hopefully some thundery activity develops

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 14:51
by tich
Razor wrote:Some impressive hail accumulations on the western side of town at present.
Only heavy rain in Ilam (where I was working) at the time, but heard several big claps of thunder.

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 15:41
by NZ Thunderstorm Soc
Another dark line approaching from the South extending from out of the TV area towards BP.
Looks evil but lacking any action from it. Light wind variating 'twixt NW and east here.
Yes, I heard the thunder and saw a few flashes along a convergence line to the north of Halswell where I working today from around 10:30am.

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 15:50
by Richard
Just a heavy shower 10 mins ago,no thunder

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 17:02
by Razor
Torrential cloudburst over me at moment, in St Martins. Edit....quite possibly the heaviest rain I have ever seen in Christchurch in all my years here, chaos with roads flash flooding. Its west coast rain!

Re: High Risk for Thunderstorms Canterbury 28th and 30 Nov.

Posted: Fri 28/11/2014 17:35
by NZ Thunderstorm Soc
Yes, well, that darkline moved over and was rather pathetic :(
A few spits of drizzly rain and that was that :-$
Calm here now and overcast with mid-range cloud.
I'd like to know where the severe storms were today as mentioned by MetService in their Severe Thunderstorm Warnings?