Cyclone Cook - The latest tracking and situation for New Zealand (+Maps) | WeatherWatch.co.nz

Cyclone Cook - The latest tracking and situation for New Zealand (+Maps)


Cyclone Cook crossed New Caledonia last night as Severe Category 3 cyclone, today it's weakened to a Category 2 system and will continue to weaken as it tracks south.

But what exactly does "weaken" mean in this scenario? And why all the warnings of flooding if Cook is so small?

As a cyclone tracks south it loses the warm core that fuels it as it tracks over cooler ocean waters. This process means the storm "technically" loses its cyclone status. As the storm "weakens" a few things happen. The peak winds ease back. The air pressure rises. The total size of the storm (centre with severe weather) often shrinks. Storm surges under the eye reduce in height.

However the rain can remain - and in this case it's more complicated than just Cook as the rain may actually intensify.

Cook just on its own may prompt some concerns of wind damage and flooding right near the centre - but the reason for all the concern this week is to do with a large low in the Tasman Sea and the connection between this and Cook that will produce a secondary area of intense, slow moving rain over places like Bay of Plenty, East Cape and Hawke's Bay.

The rain bands are intense but narrow - just like with Cyclone Cook. This means many people won't be impacted by severe weather - but those who are impacted could be exposed to significant torrential rain and as we've seen since March even in small pockets this can cause major flooding.

If you look at the rain maps for Wednesday, Thursday and Friday for the North Island you can see very intense areas of rain but 100kms east or west of it conditions are much drier/normal (see map for Thursday night below for an example).

This fine line between stormy and normal is why some forecasts are chopping and changing - and why the percentage of rain may also be jumping for some in the north (like Auckland which is so far mostly on the outer fringes of the heaviest rain).

At this stage landfall looks possible around East Cape on Friday morning - but the models are still fine tuning it. A direct hit is possible, so too is a near brush to the east. Either scenario paints the same forecast though - rain looks to be main issue and those in the upper, in particular north eastern, North Island should be up to date with all official warnings and the latest news and forecasts over the coming days.



10am (NZT) track map for Cook - Fiji Met


Ensemble showing various computer models. The general trend shows eastern BOP and East Cape as highest risk candidates for a direct hit from the small but intense low.


Rain map for Thursday night shows two things - Cyclone Cook (or Ex-cyclone Cook by then) to the north and connected to that over the North Island is a band of very intense rain - but to the west and east it's dry, putting places like Whangarei, Auckland and Hamilton on the cusp of heavy rain.

- WeatherWatch.co.nz 


Comments

Safe flights.

Hi there I am heading over to New Zealand this Sunday for a sporting tournament in Hamilton. Is it likely that the tournament would be cancelled or flights cancelled delayed. Are there any major sporting events in New Zealand being cancelled? Or is it hard to say. Thanks Ben

Hi Ben, there may be some

Hi Ben, there may be some downpours on Sunday but the weather isn't major around then (at this stage anyway). The worst of the weather has now cleared the upper North Island of New Zealand and is tracking southwards into the South Island.

Keep an eye on our detailed Hamilton forecasts, but hopefully should be all good for you.
Regards,
WW

Auckland, Rotorua and Wellington

Hi there, We were visiting NZ North Island for the first time. We would like to know when which days would be affected severely and which are normal. Here is our timetable 15-17 17- 20 20-22 Auckland Rotorua Wellington Thanks and we appreciate your help.

Kia Ora Shay, At this stage

Kia Ora Shay,

At this stage we don't see further severe weather in these areas. Keep up to date with NZTA's highway website for any possible detours or road closures as a result of slips or flooding, but hopefully things should be ok for you then. Have a safe and enjoyable journey :)

- WW

Safe to fly to Auckland on Tuesday

Hi could you please tell me if my daughter is safe to fly to Auckland next week ?

Hi there - yes next Tuesday

Hi there - yes next Tuesday looks much much better than today does. Things are a little unsettled around NZ but Tuesday should be better.

Cheers
WW

South Island?

Heading to NZ south island on Saturday for the first time from overseas, will the cyclone be heading down there at all? Thanks

Hi there - the good news is

Hi there - the good news is that it will be clearing around then - sunny weather moving into some eastern areas.

Have a great trip here - and welcome!

- WW

Hi there will cyclone cook

Hi there will cyclone cook hit palmerston north?

Hi there - take a look at our

Hi there - take a look at our latest video as it shows where the low is going to track tonight. Yes you have a chance of wind and rain for time on Friday morning and it has the chance of being severe for a time too, so keep up to date with your local forecasts and any possible MetService warnings etc. Hopefully it won't be too major but there's a risk of damage with this system as it passes by.

Cheers
WW

Hi my parents are flying from

Hi my parents are flying from Hamilton to Christchurch leaving tomorrow at 3 pm, is there any chance of delays or cancellations? Thank you !

Hi there That's not my

Hi there

That's not my decision to make. However I don't think the weather tomorrow would lead to cancellations re Hamilton to Chch. :)

WW

What time is Cyclone Cook hitting Auckland

Hi, What time is Cyclone Cook meant to hit Auckland. Approximately how long will the intensity stay in this region as well Is there a greater chance of damage on Auckland east or west coast region. Thanks Gary

Hi there Gary. Cook won't

Hi there Gary. Cook won't directly hit Auckland as it's well out east of the city but severe weather will hit eastern areas more likely than western. Great Barrier Island is most exposed, as are the Gulf Islands. But the city is on the edge of it (and may or may not get severe weather).  Peak time for rough weather is now to 6pm - after that the winds may pick up from the west but the storm will be moving in over Bay of Plenty and heading away from Auckland.

Cheers

Phil

Expectations

Daughter flying in to Aukland from Cook Islands....I am in Massachusetts, USA. Nervous wreck to say the least. How does it look for flights?

Cook

Weather in Auckland is light rain with light wind currently. It is 2.45pm local time on Thursday the 13th of April. Airports have cancelled a few flights further down the Country but if your daughter is flying into Auckland she should be fine. Worst case scenario is they will divert the flight 3 hours across the Tasman to Sydney but I've never heard that happen in 53 years on my living here. Forecasters had down graded the wind forecasts here. We will get some rain in Auckland for sure but nothing as sinister as further down the Country.

Hi

I'm in Christchurch but I know a lot of flights are being delayed here to the north island. So I'm not sure you will get back anytime soon I would check with your airline though

Hi there Out of my field of

Hi there

Out of my field of expertise sorry, best bet would be to contact the airline your daughter is flying with and ask them.

I'm sure she'll be fine though :)

WW

Computer model

In simple terms, how is a cyclone tracked and at what point can a meteorologist state categorically on its trajectory? I guess there are computer models that you feed information into, but what are the variables and what individual skill (as opposed to computer models) is needed to decipher the information? I suppose different experts will determine different outcomes, is that so? Thank you.

Cyclone

Call the next one cyclone whirly bird hahaha I can just imagine the news lady saying it.

Cyclone

Hi there, I may not know much about this but all Cyclones, tornados and hurricains are in alphabetical order, so we would need to have lots more to get to w, also cyclones only have one name so it would have to be whirly, and all the names are already made, they have all the names for cyclones up to 5 years prior, and name them the premade names when come along :3

New Cyclones

Hi Philip, could you please let the powers that be know that if there happens to be a Tropical Cyclone develop that requires an F name, that I would like to suggest it be called F#&@%ff. Cheers, Gerald.

Cyclone cook

Hahahaha definitely

Hahaha!! Definitely, we'll be

Hahaha!! Definitely, we'll be the first to let the World Meteorological Organisation know! Cheers Gerald! :) 

Phil

 

Use of word impact

Hi Rather than use the word impact in your report, it would be more correct to use affected. Impact implies a blow or collision whereas people are affected by weather. Just a point. Andrea

Hi Andrea - thanks for the

Hi Andrea - thanks for the message and thoughts. We use the word "impact' simply because it means 
"strongly affected". To be honest, if a cyclone makes landfall that is actually weather colliding with people and infrastructure, beyond being "just affected". But definitely take onboard your comments.

Cheers
Philip Duncan

You mention it's weakening as

You mention it's weakening as it approaches nz, yet on most model runs they appear to show central pressure deepening not long before landfsll, would this indicate a transition into an extra tropical cyclone?

Hi there, cyclones are tricky

Hi there, cyclones are tricky to track in our part of the world as they transition out of being tropical fuelled and into being a whole new system. The general story above is about a cyclone leaving the tropics and approaching NZ - but yes as it transitions into a cold core just shy of Northland it changes shape and becomes more of a typical Southern Ocean looking storm - or more technically an Extra Tropical Cyclone as you mention, this occurs as it tracks southwards past Gisborne and Hawke's Bay quite often. So it will weaken before reaching NZ - then deepen again as it transforms into a different storm system offshore from NZ (we hope!).

Tropical storms have most of the severe weather near the middle but extra-tropical lows see a lot of the weather shifting around and stretching away from the centre. They can be tricky to forecast due to all this chaos in the structure as it comes into our part of the world.

Hope that helps!
Cheers
WW

Cyclone naming

Hi, Why is it that having had Cyclone Deidre we are now talking Cyclone Cook?. I thought the naming convention was alphabetical/sequential ie: we should be talking of a Cyclone beginning with the letter E. Thanks, J

It's to do with where the

It's to do with where the cyclone forms from memory, you are right but yeah due to the different basins in which the storms form will determine where they are up to. Go here: https://en.wikipedia.org/wiki/Tropical_cyclone_naming

Scroll down a little and you'll see the different regions as such.

Hope that helps. :)

Cheers
WW

Cook

Hi Phil Great work on the storm updates again, you guys lead the way in this regard. With the storm being small, any shift in track will have a big impact on the weather on land. I guess it all depend on the steering high pressure systems to determine the final outcome? Cheers Dave

Hi Dave, thanks very much.

Hi Dave, thanks very much. Yes the cyclone is very small in size but potent in the middle - it may well miss a number of populated places but a slight shift west may exposed Northland and Auckland more - but currently that isn't too strong in the modelling.

Of course every day we see shifts in the models too - yesterday landfall was likely in eastern BOP at 2am on Friday, today landfall looks likely over East Cape later on Friday. It may well change again today as the computers start fine tuning their various forecasts. It's our job to find the one we think is most reliable or likely and go from there.

Cheers
Phil

the total area of the storm increases

you mean the total area of the storm increases?

No, the stormy part (severe

No, the stormy part (severe weather portion in the middle) shrinks - the low itself can get bigger though as the air pressure rises and the system unravels and spreads out the energy.  But the stormiest zone at the centre with hurricane force winds shrinks usually.

Cheers
WW