Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-21st

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melja
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by melja »

Oh sorry the west coast lol


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NZstorm
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by NZstorm »

Looking like the EC is trending toward GFS solution and Gita making landfall upper South Island.

Significant rain likely upper South Island including Canterbury/Lower North island with EC showing 200mm+ over high ground. Snow levels dropping on the ranges south of Arthurs pass, possibly as low as 1000m. Biggest wind impacts look to be on Taranki and SI West Coast.

Obviously still some unpredictability with this storm.
Chris Raine
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Chris Raine »

Metservice in a Stuff article this morning admit Gita may make landfall in upper South Island
spwill
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by spwill »

GFS inside 6 days range is a very good weather model.

Humid weather has returned here this morning, 21C dps now.
Richard
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Richard »

Thats right, GFS have been consistently picking Gita's path crossing the top of the SI which is looking the most likely now.
Cyclone Tracy
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Cyclone Tracy »

GITA is slowing and slightly more east on the latest 18z runs for Monday morning..... :smile:

viewtopic.php?f=9&p=173469#p173469

Here is the latest EC ensemble for 1602 12Z
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TonyT
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by TonyT »

Richard wrote: Sat 17/02/2018 11:56 Thats right, GFS have been consistently picking Gita's path crossing the top of the SI which is looking the most likely now.
I dont think you can say anything is most likely yet, there is still a lot variation in the ensembles. And to be fair, many of the ECMWF ensemble members have been tracking over the Cook Strait region for quite a few days, but the ensemble mean has been dragged north by a few (assumedly) rogue tracks north of the North Island.

Its worth mentioning that the Access-G has been consistently suggesting Gita will not cross NZ at all, but will spin up west of the South Island, do a loop, and decay there.
Bradley
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Bradley »

Latest JTWC forecast track map has it crossing over the top of the South Island and coming out around Blenheim, taking rverything into consideration I think the end path will be plus or minus 100 km of this map, just my opinion...
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spwill
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by spwill »

I see the Metservice high confidence of heavy rain over northern and central NZ in yesterdays severe weather outlook has moved south today to the upper South Island/lower NI.
Cyclone Tracy
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Cyclone Tracy »

GITA currently at 22.33 S 166.30 E and inching WSW. Possibility New Caledonian land friction has caused her to slow more than all models anticipated. JTWC map from yesterday is already out for 100 km on her placement at this moment.

One of the first models to run 00z for the day, the BoM’s Access R has had to re-adjust GITA’s placement in 60 to 72 hours to approx. 150 km more north west than the 12z run.
Chris Raine
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Chris Raine »

Questions being asked on the West Coast is the position of Gita similar to Ita i.e. will North Westland Buller get hammered by severe gale south easterlies and consequential damage as in 2014 from Ita ?
Bradley
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Bradley »

TonyT wrote: Sat 17/02/2018 12:26
Richard wrote: Sat 17/02/2018 11:56 Thats right, GFS have been consistently picking Gita's path crossing the top of the SI which is looking the most likely now.
I dont think you can say anything is most likely yet, there is still a lot variation in the ensembles. And to be fair, many of the ECMWF ensemble members have been tracking over the Cook Strait region for quite a few days, but the ensemble mean has been dragged north by a few (assumedly) rogue tracks north of the North Island.

Its worth mentioning that the Access-G has been consistently suggesting Gita will not cross NZ at all, but will spin up west of the South Island, do a loop, and decay there.
GFS now in agreement with ACCESS and has Gita spinning up west of the South Island and doing a loop then decaying...
Chris Raine
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Chris Raine »

I asked that very same question to Metservice this afternoon i.e will Gita cross over or just weaken off the West Coast .BSCH suggests the latter
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TonyT
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by TonyT »

Chris Raine wrote: Sat 17/02/2018 17:05 Questions being asked on the West Coast is the position of Gita similar to Ita i.e. will North Westland Buller get hammered by severe gale south easterlies and consequential damage as in 2014 from Ita ?
Those cards are certainly still on the table Chris, but unfortunately so is most of the rest of the pack! My gut feel is no to the strong easterlies. I'm starting to come more to the idea that the remains of Gita are going to split and some of it will cross to the east, and some will remain off the West Coast. This could end up rather similar to Fehi with a very messy weather map to draw on Wednesday morning! Still a lot to happen before there is much confidence in any outcome though.
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TonyT
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

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Chris Raine wrote: Sat 17/02/2018 17:11 I asked that very same question to Metservice this afternoon i.e will Gita cross over or just weaken off the West Coast .BSCH suggests the latter
Its starting to look as though the timing of the possible interaction with the polar trough will be out, and there could be just enough high pressure east of the South Island to keep the depression sitting west of the country. I'd say all bets are off at this time.
Chris Raine
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Chris Raine »

That's good Tony.My house lost its carport roof with Ita at Runanga
Razor
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Razor »

I'm really worried for the West Coast in this event, its looking pretty darn rough
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Chris Raine
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Chris Raine »

Civil Defence and Health are preparing their emergency management response if required for Tuesday & Wednesday
Chris Raine
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Chris Raine »

Earth Null school has interesting maps .Swell map is a worry
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Nev
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Nev »

3am track-map from MetService…

TC Gita - TCWC Wgtn Track-map - Feb 17, 1403z.png
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Cyclone Tracy
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Cyclone Tracy »

GITA is a shadow of her former annular TC structure but still punching out decent winds. Moving more SW now. Model agreement pretty good for 1am's Tuesday after the SE turn tomorrow. BoM's latest Access R (18z) showing her a little more north and also has the southern trough a little more north as well.
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Cyclone Tracy
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Cyclone Tracy »

Norfolk Island's 11.30am AEST BoM baro MSL reading was 1008.7 hPa and slowly falling. All the big models assume it won't drop below 1008 hPa in the next 6 hours. Watching this observation like a hawk ;)

http://www.bom.gov.au/products/IDN60801 ... 4996.shtml
Blowy
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Blowy »

Dropped below 1008.. now what?
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TonyT
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by TonyT »

Blowy wrote: Sun 18/02/2018 17:11 Dropped below 1008.. now what?
Break open the popcorn...
Cyclone Tracy
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Re: Ex-Tropical Cyclone Gita impacts NZ Feb 18th-20th

Unread post by Cyclone Tracy »

It's the first real quality land observation test for a while against the models with GITA close by. Holding on 1007.9 but if it drops more, it's indicating a slight movement east. Models indicated it should start rising again around 7pm NZT.