Brand New GFDL much further LEFT

[logybogy]

[WeatherEmperor]

That is scary. The GFDL is perhaps the NHC's most trusted model and if it turns more towards FL that is not good. But I am still going to wait for the data from the NOAA jet and the model runs from that data to fully see what is happening.

<RICKY>

[das8929]

Wow only one of those models doesnt show a hit on Florida!

[Stratosphere747]

Umm....Only one of those models show a hit on Fla...

[dhweather]

Actually, only one shows a hit on Florida, the
rest show a trend.

[Weatherboy1]

I would disagree that the GFDL model is one of the NHC's most trusted models. Its performance has been hit or miss on various storms. But it IS significant that it shifted substantially westward. As opposed to hooking N-ward along 74W, Frances is progged by this model to hook N-ward along 77W. That makes me more nervous.

[Air Force Met]

I would disagree that the GFDL model is one of the NHC's most trusted models. Its performance has been hit or miss on various storms. But it IS significant that it shifted substantially westward. As opposed to hooking N-ward along 74W, Frances is progged by this model to hook N-ward along 77W. That makes me more nervous.

It and the NOGAPS have been the 2 "rightwingers" of the bunch. Now even they are coming around.

[wxman57]

I've noticed that NOGAPS and GFDL have been the two worst models with Frances so far - each forecasting a turn to the north at about 72 hours all along Frances's track. The GFS has been one of the better models so far, along with LBAR for some goofy reason. I guess a busted clock is right twice a day.

I think that some of the models may underestimate the tendency for a major hurricane to pump up the ridge to the north and continue moving more westward than forecast. Thus, I think south Florida is really under the gun here.

Also, the general tendency for most of the dynamic models this season has been too slow and too far north. Not good for south Florida, either.

[Steve H.]

Obervation Here. The models seem to be slowly converging on a solution, which while not looking good at the moment, could change quite a bit over the next few days. The good news is that Frances is moving slowly. This may buy more time for the pattern to cahnge before getting closer to the Bahamas and thereafter. The bad news is, I don't quite buy some of the slower models. Once the ridge rebuilds and flexes some muscle, I would expect that she will begin to pick up forward speed, then begin to strengthen when she gets to the base of the ridge. The fact that Hermine formed tells me that when hermine evacuates to north/northeast, as well as what's left of Gaston, we will get a ridge rebuilding that's stronger than progged earlier today. This may be what the models are picking up on, particularly the one's that were the right outliers. Still early in the game, but I think by Tuesday night/Wednesday, we should have a pretty good idea of where this is going. It gets a bit easier to predict when you get stronger steering currents as this ridge should provide. This still could end up in the GOM after crossing somewhere on the Fl peninsula. Nail biting time

[Stormsfury]

I've noticed that NOGAPS and GFDL have been the two worst models with Frances so far - each forecasting a turn to the north at about 72 hours all along Frances's track. The GFS has been one of the better models so far, along with LBAR for some goofy reason. I guess a busted clock is right twice a day.

Blind squirrels find acorns once in a while ...

Actually, the LBAR is quite good with storms in the deep tropics, but once recurvature points, and TC's get north of 20º, fuhgetaboutit ...

I think that some of the models may underestimate the tendency for a major hurricane to pump up the ridge to the north and continue moving more westward than forecast. Thus, I think south Florida is really under the gun here.

Also, the general tendency for most of the dynamic models this season has been too slow and too far north. Not good for south Florida, either.

Interesting points and pretty much agree.

This time around, the ECMWF is progging an extension of the WATL ridge over South Carolina which will serve to keep Frances south of the Carolinas and keep Frances moving westward or WNW ... and even more so frightening, conditions looking at the other height maps, support a potential deepening storm coming in ... but we'll not discuss that part this far out ...

[Scott_inVA]

I've noticed that NOGAPS and GFDL have been the two worst models with Frances so far - each forecasting a turn to the north at about 72 hours all along Frances's track. The GFS has been one of the better models so far, along with LBAR for some goofy reason. I guess a busted clock is right twice a day.

I think that some of the models may underestimate the tendency for a major hurricane to pump up the ridge to the north and continue moving more westward than forecast. Thus, I think south Florida is really under the gun here.

Also, the general tendency for most of the dynamic models this season has been too slow and too far north. Not good for south Florida, either.

Frances verification thru 96 hours as of 29 Aug 18Z:
LBAR still First Place
GFDL goes to second
TPC drops to third ( but only by a mile or so)
GFS is fifth
NOGAPS is in eigth place
UKMET and A98 are performing worse than NOGAP...with Frances, that's saying something!

Scott

[caneman]

I've noticed that NOGAPS and GFDL have been the two worst models with Frances so far - each forecasting a turn to the north at about 72 hours all along Frances's track. The GFS has been one of the better models so far, along with LBAR for some goofy reason. I guess a busted clock is right twice a day.

I think that some of the models may underestimate the tendency for a major hurricane to pump up the ridge to the north and continue moving more westward than forecast. Thus, I think south Florida is really under the gun here.

Also, the general tendency for most of the dynamic models this season has been too slow and too far north. Not good for south Florida, either.

Frances verification thru 96 hours as of 29 Aug 18Z:
LBAR still First Place
GFDL goes to second
TPC drops to third ( but only by a mile or so)
GFS is fifth
NOGAPS is in eigth place
UKMET and A98 are performing worse than NOGAP...with Frances, that's saying something!

Scott

I'm sure you get your info from reliable sources. But it seems to me that GFS has outperformed GFDL. Am I missing something?

[wxman57]

I've noticed that NOGAPS and GFDL have been the two worst models with Frances so far - each forecasting a turn to the north at about 72 hours all along Frances's track. The GFS has been one of the better models so far, along with LBAR for some goofy reason. I guess a busted clock is right twice a day.

I think that some of the models may underestimate the tendency for a major hurricane to pump up the ridge to the north and continue moving more westward than forecast. Thus, I think south Florida is really under the gun here.

Also, the general tendency for most of the dynamic models this season has been too slow and too far north. Not good for south Florida, either.

Frances verification thru 96 hours as of 29 Aug 18Z:
LBAR still First Place
GFDL goes to second
TPC drops to third ( but only by a mile or so)
GFS is fifth
NOGAPS is in eigth place
UKMET and A98 are performing worse than NOGAP...with Frances, that's saying something!

Scott

Perhaps my perception about the GFDL recurving it too much is based on post-96hr positions.

[WeatherNole]

Obervation Here. The models seem to be slowly converging on a solution, which while not looking good at the moment, could change quite a bit over the next few days. The good news is that Frances is moving slowly. This may buy more time for the pattern to cahnge before getting closer to the Bahamas and thereafter. The bad news is, I don't quite buy some of the slower models. Once the ridge rebuilds and flexes some muscle, I would expect that she will begin to pick up forward speed, then begin to strengthen when she gets to the base of the ridge. The fact that Hermine formed tells me that when hermine evacuates to north/northeast, as well as what's left of Gaston, we will get a ridge rebuilding that's stronger than progged earlier today. This may be what the models are picking up on, particularly the one's that were the right outliers. Still early in the game, but I think by Tuesday night/Wednesday, we should have a pretty good idea of where this is going. It gets a bit easier to predict when you get stronger steering currents as this ridge should provide. This still could end up in the GOM after crossing somewhere on the FL peninsula. Nail biting time

Steve touched on a very good point here. The premise that Frances will move in some sort of a westerly direction is based on building, strong high pressure to the north. Strong high pressure to the north would lead to a somewhat rapid westerly component to the movement. A slower movement is more in line with a weaker ridge of high pressure, and of course a weaker ridge would allow for more of a northerly component to the movement. I'd keep an eye on what the models do with the ridge the next few runs - which is strongest, weakest, etc.

Mike

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