GFS trend on the next CV wave

x-y-no · #1 Postby **x-y-no** » Wed Aug 03, 2005 12:01 pm

The GFS has been trending more and more bullish on developing the wave currently SW of the CV islands, although today's 12Z run is just a little less so than the 6Z run.

The model has been doing it's usual track flip/flop with the 0Z/12Z vs 6Z/18Z runs - I think this is a product of the age of initialization data. The 0Z/12Z runs have been further right.

In general, though, the trend has been very consistant about developing this but turning north before reaching the islands.

Here are the surface plots of the last 3 runs, valid at 12Z on the 10th:

Note that the following wave is looking interesting as a potential Caribbean threat.

The runs are consistant in turning the system NNE at this point and deepening it - although a later turn back to the NNW seems possible:

(valid 12Z on the 15th)

The following wave shows here south of Cuba.

Jan

x-y-no · #2 Postby **x-y-no** » Wed Aug 03, 2005 12:07 pm

And just for the entertainment of us South Florida folks ...

Frank2 · #3 Postby **Frank2** » Wed Aug 03, 2005 12:08 pm

Of course this forecast is many days in the future, but, overall it continues to indicate the weakness in the subtropical ridge.

I must admit, the more I read here and hear in the news, the more I'm convinced that the seasonal totals will either not be nearly as high as forecast, or, they might be high, but, will feature mostly oceanic systems.

Frank

#4 Postby **alicia-w** » Wed Aug 03, 2005 12:08 pm

similar to Georges?

MortisFL · #5 Postby **MortisFL** » Wed Aug 03, 2005 12:10 pm

x-y-no wrote:And just for the entertainment of us South Florida folks ...

haha, the always so reliable 15 day GFS...

x-y-no · #6 Postby **x-y-no** » Wed Aug 03, 2005 12:12 pm

Frank2 wrote:Of course this forecast is many days in the future, but, overall it continues to indicate the weakness in the subtropical ridge.

I must admit, the more I read here and hear in the news, the more I'm convinced that the seasonal totals will either not be nearly as high as forecast, or, they might be high, but, will feature mostly oceanic systems.

Frank

It's all in the timing. It stands to reason that if one has a high number of storms, some of them will be fish.

I still think the mean ridge will be strong enough this season that we'll face several serious lanfalls in the next couple of months.

Jan

#7 Postby **TreasureIslandFLGal** » Wed Aug 03, 2005 12:26 pm

looking at the long term gfs for ridge placement, this first storm may not hit the us and go fish. If it does however, the next storm could ba an east-coaster or GOM event. Then, down the road, once that first one has headed way north and become subtropical, the ridge would be able to build back in, letting anything else down the road be able to ride the southern periphery again for a while until the ridge could pull back again.
That's all pure conjecture, but I have noticed how the ridge seems to "breathe" throughout the season, inhale -cross florida, and exhale -pull out to the east of florida... it is currently exhaling since Harvey is pushing on the "lung".

#8 Postby **WeatherEmperor** » Wed Aug 03, 2005 1:14 pm

It is okay for some to be fish you know? it does happen and its perfectly normal.

<RICKY>

floridahurricaneguy · #9 Postby **floridahurricaneguy** » Wed Aug 03, 2005 1:28 pm

No offense frank but you keep trying to play down the season how we are not going to have many and all will be fish. Everyone else says differently! Dr Gray's forecast and NOAA's espically. Its time you face the facts. Not trying to be mean but its the truth. They are not all going to be fishes, I have the feel after this next wave we will resume more making landfall.

Matt

#10 Postby **deltadog03** » Wed Aug 03, 2005 2:05 pm

ok, thanks for the maps...i take them wth a MAJOR grain of salt...all of the US models have and continue to be way too far north intially....we will see if anything develops...my bet yes, we will see...thanks again for the maps

#11 Postby **bvigal** » Wed Aug 03, 2005 2:18 pm

Hey, don't anyone pick on Frank! I've seen his posts for 3 years on another forum. He's very level-headed, used to work at NHC, and has a lot of experience to temper his opinions.

Last I heard, all opinions are welcome here, right? When it gets fast and furious and everyone's adrenaline is on overdrive, Frank will be the voice of reason and calm! :wink:

WindRunner · #12 Postby **WindRunner** » Wed Aug 03, 2005 3:00 pm

Well, I saw another model (somewhere, don't remember which) that developed the same two waves, so I'd say it's a pretty good bet that we'll get these two after harvey.

#13 Postby **deltadog03** » Wed Aug 03, 2005 3:02 pm

I agree development looks pretty good...I still think this heads almost due WEST....we have seen it already...2 times i believe...the forecast NW or NNW...and boom W....im sticking too that...lol....

x-y-no · #14 Postby **x-y-no** » Wed Aug 03, 2005 5:33 pm

18Z run - a little slower and a bit more southerly at first, but basically recurving in the same area.

Loking a little more enthusiatic about the following wave. I'll post a later frame when it's out ...

#15 Postby **deltadog03** » Wed Aug 03, 2005 5:40 pm

thanks for the pics of the global fairy system...lol...I don't buy it though...i was looking at the upper level and lower level winds...they all suggest that the ridge is there and is not budging...I would tend to believe a W or WNW will continue until at least the lesser antilles...

x-y-no · #16 Postby **x-y-no** » Wed Aug 03, 2005 5:49 pm

deltadog03 wrote:thanks for the pics of the global fairy system...lol...I don't buy it though...i was looking at the upper level and lower level winds...they all suggest that the ridge is there and is not budging...I would tend to believe a W or WNW will continue until at least the lesser antilles...

With all models, the idea is to look for trends (which is why I gave the same timepoint from multiple runs in the firs post) and in particular to look for trends in the synoptic setup.

When for instance (as in this case) many runs in a row have developed a system and also a similar weakness in the ridge into which it recurves that system , one can begin to have more confidence in that forecast, even if it is six or seven days out.

Used properly, the GFS is as valuable a tool as any other global model. Sure it has quirks and biases, and sometimes it's just totally out to lunch - but the same can be said for any of them.

Jan

EDIT: The UKMET, European and Canadian model all recurve this system in much the same area and timeframe.

artist · #17 Postby **artist** » Wed Aug 03, 2005 5:50 pm

Frank2 - glad to have you posting here and to hear your insight! Do you mind my asking how long you worked for the NHC? Look forward to your thoughts this season!
(sorry if off topic)

vacanechaser · #18 Postby **vacanechaser** » Wed Aug 03, 2005 5:57 pm

Frank2 wrote:Of course this forecast is many days in the future, but, overall it continues to indicate the weakness in the subtropical ridge.Frank

That weakness on the GFS is normal it seems. I just think that it has a better shot at coming westward than the GFS shows. The bias with the GFS is to always recurve the storms into the Atlantic ths far out. There have been a few times that it has not, but most times, you just cant trust it. JMO.

Jesse V. Bass III
http://www.vastormphoto.com
Hurricane Intercept Research Team

x-y-no · #19 Postby **x-y-no** » Wed Aug 03, 2005 5:58 pm

One more frame from the 18Z run ... kind of stalling the first system (because original motion was slow enough that the ridge is building back in the NE Atlantic, blocking the recurvature), and the following wave is turning north in its trail.

I think the faster solution for the first system is more likely, allowing the following system to proceed towards the islands.

Way early to make that a definite call, though.

Jan

GFS trend on the next CV wave

GFS trend on the next CV wave

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