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#11 Fish

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Posted 07 March 2018 - 10:26 AM

I really don't think you can say one forecast or the other is any more accurate at this timeframe out.

By the sheer nature of tropical revolving storms, you can't accurately predict their path with any certainty more than a few (2 or 3) days out. That is the whole thing with them re-curving - it is not predictable.

 

When two or more separate forecasts starting agreeing on a track, that is when the forecasts start becoming more reliable.

 

That said, the in-house Predict Wind forecasts aren't good for cyclones. My logic is that those forecasts were developed and fine tuned for 'mid range' wind, i.e. good sailing breezes. The European and US forecasts are more focused around 'public good' such as predicting server weather events. Already we are seeing those forecasts with more plausible tracks than the in-house Predict Wind ones.


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#12 John B

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Posted 07 March 2018 - 10:51 AM

No , but on monday we'll see . 

:razz:

 Thats interesting you say that about PWE and PWG .They didn't pick up  the late season cyclones last year very early... Ella / Donna ... one or both of those.

 

 Good ole GFS did.


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#13 DrWatson

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Posted 08 March 2018 - 01:48 AM

So, if the trees on the council land next to my place fall on my shed during this storm... Who pays?


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"Si Dieu n'existait pas, il faudrait l'inventer"

 


#14 wheels

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Posted 08 March 2018 - 05:14 AM

 

I really don't think you can say one forecast or the other is any more accurate at this timeframe out.

By the sheer nature of tropical revolving storms, you can't accurately predict their path with any certainty more than a few (2 or 3) days out. That is the whole thing with them re-curving - it is not predictable.

 

When two or more separate forecasts starting agreeing on a track, that is when the forecasts start becoming more reliable.

Exactly right Fish. There are many variables that enter the equation. The computer modelling is only as accurate as the info punched into them. The new Super computers do a great job, but there is still some info that can never be entered because the info can't be "seen" to be able to be entered. As the event comes closer in time, the more accurate and comprehensive the info able to be entered becomes and thus the greater the accuracy.

There is actually very little difference between in accuracy between the various prediction programs we can subscribe to. Where the variables actually are, is in what they are actually telling us. So for instance, some will tell us the Sustained wind strength. Others may use peak or average strength. Some use average rain intensity, others the max possible. So the models look different in how thy are presented to us, but are actually ver close to being the same. And mainly this is because they all use the exact same base data.

This possible Cyclone I can't see affecting us much. Maybe heavy rain for the Far North. But the current weather os pushing a massive amount of cooler Southerly air up into the Pacific. Cold air is drier and so there is not as much moisture in the Air. A cyclone needs warmth from the Sea and lots of moisture laden air to survive. As it drops toward us, the thing is going to run out of steam I reckon. But that is my amateur view of the situation.


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#15 Fish

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Posted 08 March 2018 - 11:26 AM

Current Metservice situation for Auckland.

This is the first time I've ever seen this, and it is the most accurate forecast they could come up with!

 

It states explicitly that there is uncertainty as to the track of the cyclone. It does say a cyclone is coming and when it is roughly expected. but instead of givign afulse sense of security around its likely track, they are just saying there is 'uncertainty'.

 

Valid to: Midnight Friday 9 Mar 2018
Issued: 11:02am Thursday 8 Mar 2018
Warning: Wind warning Nil

Situation: A low over the upper the region moves away to the east late Friday. A ridge spreads over the North Island Saturday. Cyclone Hola approaches from the north late Sunday into Monday. The track of the cyclone still remains uncertain,but current forecasts expect a southeast track near northeastern parts of the North Island.


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#16 muzled

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Posted 08 March 2018 - 11:29 AM

Would have been much more fun if they'd called it cyclone 'how the f*ck are ya' than just Hola.


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#17 John B

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Posted 08 March 2018 - 12:17 PM

The value to a cruising yotty of seeing which forecast model ends up being accurate a week out is you add it to your quiver of similar observations and develop a trend as to which model is more right than wrong in any given season.

 

 Over the years, some seasons  I've seen metvuw bang on and metservice  either just plain wrong or so conservative they may as well be wrong.

 Then another year , olliversudden, metservice is right and metvuw drags the chain.

Add to that the generic overseas forecasts and start figuring out which models the various outfits are using and apply that to the trend .

 So  I'm not looking at one event , Hola, but I would look at that plus the cyclones that have been plus the ones to come  and  by end of may ,  hopefully be able to conclude one forecast model  is more reliable this year. ( if we were going again this year but lets not discuss that)

 

 Last year as an example  going to and coming back from the Islands for us it was GFS for serious stuff like gales and cyclones, and ECMWF or one of the PW models for day to day  0 to 25 knot type stuff.( and especially if you could get them all to generally agree) Plus local knowledge of course.


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#18 Sabre

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Posted 08 March 2018 - 03:20 PM

Hola sounds and looks a bit too much like Bola for my liking.
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#19 Black Panther

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Posted 08 March 2018 - 03:32 PM

Hola is just a friendly greeting. It's a nice cyclone.
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“If we don’t change our direction, we will end up where we are headed.”

 


#20 Knot Me... maybe

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Posted 08 March 2018 - 03:38 PM

Hola sounds and looks a bit too much like Bola for my liking.

Gets freakier when you add in the the mix the word Hola is derived from the word Allah.

 

Maybe rather than a whistling sound we'll hear 'Ali Akbar motherfornicator' instead......


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