Subtropical Low/TC Innis 20th-21st Feb

[CHCH Weather Chaser]

Wow, overnight models are suggesting a lot more rain for Canterbury. Looking at metservice 7 day rain maps it suggests well over 50mm and GFS model showing 90mm at the moment. Something to keep an eye on thats for sure. Looks like there may be a return to westerlies and warmer weather for the east coast of the south from Tuesday possibly, just have to see how it unfolds!

[Tornado Tim]

Models are suggesting about 5mm For Auckland and Waikato.

[David]

Models are suggesting about 5mm For Auckland and Waikato.

What model are you looking at? The forecasts and models I've looked at this morning are suggested at least 20mm...

[Myself]

GFS rain fields......why the obsession here with following their output from every successive run? The GFS is too dumb to properly model rain due to its pathetic grasp of terrain and relatively poor parameterisation. But, never fail, every new run someone will get excited/upset about the latest bump in the roller-coaster.
It would be better to look at other output fields and other models and make your own mind up.

[Tornado Tim]

I agree with what you said myself.
It didn't seem enough for what I saw, btw i used http://www.arl.noaa.gov/READYcmet.php

[NZstorm]

12Z GFS suggests 50mm for Auckland off the whole event but I suspect it will be fizzer for the north with not too much rain. Maybe 15mm if we are lucky. I'll have a closer look at the models in a day or two. The east of the South Island looks like the region in the firing line for the heaviest rain due to onshore easterly.

[Namytnap]

GFS rain fields......why the obsession here with following their output from every successive run? The GFS is too dumb to properly model rain due to its pathetic grasp of terrain and relatively poor parameterisation. But, never fail, every new run someone will get excited/upset about the latest bump in the roller-coaster.
It would be better to look at other output fields and other models and make your own mind up.

lol

[CHCH Weather Chaser]

GFS 6 hours ago showed 89.2mm and now just 32.1mm. Very dramatic change. I find GFS model to be inconsitant and not very accurate. However, metservice 7 day maps still shows significant rain for Canterbury and closer to that 89mm with the adding up. I find metservice maps to be very accurate and good to watch. Thats exactly what ill be doing over the next day or two.

[Manukau heads obs]

latest gfs run looking better for rain for the NI I think

[CHCH Weather Chaser]

Yeah i agree its looking much better for the upper half of the North Island and Canterbury totals have backed off big time now. Calculating the maps showed around 100mm earlier and now only around 30mm and although GFS isnt very accurate it backs this up. Thats a bugger i was looking forward to a huge rainfall here in Christchurch. I was prepared to give up a cricket game and have it called off for big rain but now if its only going to deliver around 30mm i hope the low keeps moving north so i can play on Saturday

[Razor]

Rain can stuff right off from ChCh this weekend. I'm fundraising for kids with cancer around ChCh as an event related to the Iron Maiden concert.

If you want to support kids with cancer then please do not wish for rain- we want sun and lots of it as we drive around ChCh in the Maiden bus.

[bjb]

The sub-tropical low that models are suggesting is from the tropical depression TD10F.
The low has been hanging around between Fiji & Vanuatu for a few days.
Yesterday it showed signs of developing further and passed to the south of Port Vila last night.
Central pressure is only around 1000 and winds to gales force only.
The TD is presently passing over New Caledonia.
Radar images from meteo.nc shows a circulating rain/cloud mass.
How it develops after this will depend on the SST below New Cal.
These waters are normally warm, due to the extensive coral reef system around nc.

One to watch over future days.
Barry

[TonyT]

Rain can stuff right off from ChCh this weekend. I'm fundraising for kids with cancer around ChCh as an event related to the Iron Maiden concert.

If you want to support kids with cancer then please do not wish for rain- we want sun and lots of it as we drive around ChCh in the Maiden bus.

Good on you Razor.

[CHCH Weather Chaser]

Its looking better for you razor than it was this morning!

[bjb]

The tropical depression has now been uprated to a Cyclone.
TD10F is now Cyclone Innis, still only a category one.
All the earlier models were suggesting a move of the depression off NSW.
Then moving across the Tasman on Friday, toward the West Coast.

With it forming into a cyclone the path may be more over the North Island.
Whatever happens some of NZ will get some very stormy conditions on Friday-Saturday.

Barry

[Nev]

Hi Barry. Posted something about TC Innis on the 'South Pacific Tropical Cyclones 2009' thread. Apparrantly it caused some very minor damage when it passed S of Port Vila the previous night and strengthened into a TS before passing over New Caledonia yesterday evening. Don't think it will amount to much, but yes, adding to the moisture of that sub-tropical Aussie low by the looks.

[spwill]

Humid weather here now with Auckland dewpoints at 18/19C . Some cloud build ups around Auckland this morning producing isolated showers.

[bjb]

Nev

Thanks for the link to the thread, missed that one.
With my location my interest is obviously in tropical lows & cyclones.
Particularly at this time of year.
TD10F did pass between Erramango and Tanna early Tuesday morning.
They would have got some heavy rain and gale force winds, particularly on the west coast.
I am just pleased it formed into a TC after it left Vanuatu & New Caledonia.
We have three months to go in the cyclone season and I am crossing my fingers.

Barry

[CHCH Weather Chaser]

Metservice showing a high of 15 here on Friday and an overnight low of 17! haha! Timaru high 15 low 15. Interesting....!

[jamie]

Well its muggy already again. I just drove from Hamilton to Auckland with no aircon. Didnt mind that until i found the trafic jam. Horrible!

Would have been nice if they had put a trafic warnings on the Waikato radio stations as nearly 100% of traffic heading north into that crash come from the waikato. And even then in auckland on the radio i heard nothing and the trip ended up taking me well over 2 hours. Communication would have been good!

[spwill]

Some sea breeze convergence through Aucklands west this afternoon with some local heavy showers out that way.

[Tornado Tim]

Yea same here, some convergence in hamilton let loose some heavy showers. But completely avoided Matangi.
So this cyclone is heading for the NI eh, that will be a good chance for my weather station to get some nice extreme Values to record.

[Manukau heads obs]

yes, a shower over the eastern side of the peninsular here
the sea breeze kept if away from the western side...good thing too, as we were doing concreting today (foundations for the wind turbine!)

[CHCH Weather Chaser]

Looks like central New Zealand is in for the brunt of this system. It also looks as if its going to pass more quickly through Canterbury and not become slow moving like it was indicating early yesterday. The last 3 model runs from GFS have been consistent showing just under 55 - 60mm for Christchurch. However, the last run on the M/S maps showed the very intense stuff move slightly further south, i still reckon this low is going to take a turn yet.

[Myself]

Hello, winter. High pressure far to our southeast was part of what made last July and August so ridiculous. And to have it turn up in February like this is not good at all.
Hopefully things will turn more mobile on the model runs over the next few days!
(Chart is Monday 1AM)