ATL: FIONA - Models

[frederic79]

Latest NOGAPS shows a turn to the west at the end again according to wunderground.

[Scorpion]

Latest NOGAPS shows a turn to the west at the end again according to wunderground.

Definitely seems to be the trend. Serious FL threat IMO.

[wxman57]

Can someone answer this question for me..I've noticed the Bams seem to have an extension beyond 5 days..In this case you see hard sw motion..Where is the extended portion to give those plots? thx

No "extension", the shallow BAM just moves the system much faster than the other models. The BAM is really not a good model for the subtropics (north of 20N).

[wxman57]

Latest NOGAPS shows a turn to the west at the end again according to wunderground.

NOGAPS is probably THE worst model for TC paths. It's almost always opposite every other model. First one I throw out (after the extrapolated track).

[CYCLONE MIKE]

Frustrating looking at the model spread seeing almost a unanimous recurve and the EURO driving this storm near the NE Caribbean and EC?

It is way to early to start getting frustrated BA. We all know come tomorrow they will have changed to some degree and by monday change even more. I am just watching the models to see what they do with the upper level features. I agree with the euro btw. Earl will be pulling out with HP building in blocking 97L from following.

[ConvergenceZone]

Latest NOGAPS shows a turn to the west at the end again according to wunderground.

NOGAPS is probably THE worst model for TC paths. It's almost always opposite every other model. First one I throw out (after the extrapolated track).

I have a serious question, I don't know as much about models as others on this forum, but it seems like there are a couple of models that mets and other mention are horrible. My question is, if they are so bad, then why do they use them at all? Why not just throw them out completely?

I'm not aruging that they aren't bad, but just wondering, why are they continuing to use them in the tropics if they are that bad?

[CYCLONE MIKE]

wxman,
let me run by you what I think will happen with 97L and Earl and get you opinion. First with Earl. he will eventually turn to the NW and north and accelerate offshore off the eastern coast. Off course leaving a substantial weakness for a couple of days but it will start to fill in by the time 97L arrives. Now I really believe by this time a substantial ridge starts to build in behind Earl and blocks the northward escape route. Also will have to see if we have a strong high over the SE US at this time that could bridge with the ATL high. Not going to pinpoint an exact state for landfall but of course anyone from south FL up to the carolinas should watch very closely. Also expect the models to begin shifting more south and west in the coming days as they get ahold of the upper level conditions behind Earl. Your opinions? Thanks.

[wxman57]

I have a serious question, I don't know as much about models as others on this forum, but it seems like there are a couple of models that mets and other mention are horrible. My question is, if they are so bad, then why do they use them at all? Why not just throw them out completely?

I'm not arguing that they aren't bad, but just wondering, why are they continuing to use them in the tropics if they are that bad?

BAM models can provide some useful guidance for systems trapped in the deep tropics beneath a ridge where the steering flow doesn't change much. So they're OK for some initial guidance for easterly waves. Other models like the old LBAR don't really serve any good purpose. Don't know why it's still included. Maybe so that we know where a system WON'T track, most likely. The climo models (CLiPER) that you'll see abbreviated maybe as CLP5 is basically a climatology-persistence model used to judge how well the current forecast is doing, basically. If you can't beat climo/persistence, then you're pretty bad at forecasting.

NOGAPS just hasn't been very good at all in recent years (maybe many recent years). I usually attend all the modeling sessions when I attend the various hurricane conferences each year. The navy knows its NOGAPS model leaves a lot to be desired as far as a TC forecasting tool. When I look at a tight clustering of most of the models, I'll see one line shooting off in the other direction all by itself. That's generally NOGAPS. The modelers are trying to fix its many weaknesses, but that'll be a long time from now.

The GFS ensembles, maybe abbreviated AEMN haven't proven to be a good predictor of TC movement either.

The best "model" is actually a consensus of groups of models. Look for something like TVCN or the older GUNA. You'll find the NHC track not far from the TVCN most of the time.

Here's a link to a good discussion of current model error trends:
http://www.nhc.noaa.gov/verification/verify6.shtml

And a good page with descriptions of all the models:
http://www.nhc.noaa.gov/modelsummary.shtml

[FritzPaul]

Two things:

1. Shouldn't 97 have a hard time getting its act together because of the
upwelling of colder water caused by Danielle and Earl?

2. Why does the NOGAPS and CMC models consistently deviate from all the
other models?

Thanks, Paul

[wxman57]

Two things:

1. Shouldn't 97 have a hard time getting its act together because of the
upwelling of colder water caused by Danielle and Earl?

2. Why does the NOGAPS and CMC models consistently deviate from all the
other models?

Thanks, Paul

Actually, the Canadian model has been one of the best models beyond 72 hrs in the last 2 years. Will it be this year, too? Remains to be seen. NOGAPS just isn't a good tropical model.

[superfly]

1. Shouldn't 97 have a hard time getting its act together because of the
upwelling of colder water caused by Danielle and Earl?

It will still have plenty of warm water to form, but it may not strengthen as much as it could otherwise until it gets near the Islands.

[southerngale]

BAM models can provide some useful guidance for systems trapped in the deep tropics beneath a ridge where the steering flow doesn't change much. So they're OK for some initial guidance for easterly waves. Other models like the old LBAR don't really serve any good purpose. Don't know why it's still included. Maybe so that we know where a system WON'T track, most likely. The climo models (CLiPER) that you'll see abbreviated maybe as CLP5 is basically a climatology-persistence model used to judge how well the current forecast is doing, basically. If you can't beat climo/persistence, then you're pretty bad at forecasting.

NOGAPS just hasn't been very good at all in recent years (maybe many recent years). I usually attend all the modeling sessions when I attend the various hurricane conferences each year. The navy knows its NOGAPS model leaves a lot to be desired as far as a TC forecasting tool. When I look at a tight clustering of most of the models, I'll see one line shooting off in the other direction all by itself. That's generally NOGAPS. The modelers are trying to fix its many weaknesses, but that'll be a long time from now.

The GFS ensembles, maybe abbreviated AEMN haven't proven to be a good predictor of TC movement either.

The best "model" is actually a consensus of groups of models. Look for something like TVCN or the older GUNA. You'll find the NHC track not far from the TVCN most of the time.

Here's a link to a good discussion of current model error trends:
http://www.nhc.noaa.gov/verification/verify6.shtml

And a good page with descriptions of all the models:
http://www.nhc.noaa.gov/modelsummary.shtml

Thanks wxman57... good info.

And hmmm.... the TVCN shows a bend to the SW at the end.


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[Ivanhater]

Nice catch SG. They can blend multiple models to come up with the TVCN solution. My bet is the Euro was part of the blend this go round. Certainly seeing a ridge on the long range.

[ConvergenceZone]

thanks wxman57 for the model explanations and links...I'll check the links out....

[cycloneye]

00z NOGAPS on 97L.

https://www.fnmoc.navy.mil/wxmap_cgi/cg ... t=Tropical

Night all. Big day tommorow here.

[Vortex]

CMC 00z just misses islands but bend back west at end of run


http://moe.met.fsu.edu/cgi-bin/cmctc2.c ... =Animation

[KWT]

Yeah that CMC run once again implies a possible risk down the line, need to see what the long range run does mind you first.

The GFS has *finally* painted a realistic set with it staying weak but seperate from Earl, which is as possible as any other solution out there esp if Earl does shear it which is plauseable.

[KWT]

CMC long range keeps this offshore but its a tight call again, abit slower and to the south and the upper high would build in quickly enough to shunt this one to the west again, as it is it runs up north just to the east of the coast in a similar position as Earl.

[blp]

High building in..... its purple...
ECMWF 120hr

[blp]

ECMWF 144hr