ATL: HERMINE - Models

[Blown Away]

The track guidance has shifted mostly just north of Hispaniola all day, so land interaction should not be a big factor in future long range model runs...

[gatorcane]

I was just going through Hurricane Earls model thread and interestingly enough the models showed development for a few days and then dropped development for a few days only to start showing development again, a lot of the same people who are writing 99L off had written 97L off also. Another thing of interest I saw was that the ensembles continued to show development even when the deterministic models had dropped development....just food for thought.

Yes very good point. I mentioned this earlier today. I think folks may want to read through this thread again (link below for your convenience) before writing off 99l. Not only did Earl look as bad as 99l at one point when he were an invest but the GFS and ECMWF showed nothing but weak lows near Belize even at 96-120 hours out, but the GFS ensembles were a bit more enthusiastic (to SouthDadeFish's point). Also the HWRF was calling for hurricane while the globals were not. JMA was also bullish for JMA standards like we have here with 99l. Some people were completely writing off Earl that it would never form. Striking similarities here.

viewtopic.php?f=84&t=118096&hilit=Earl

[TheStormExpert]

I was just going through Hurricane Earls model thread and interestingly enough the models showed development for a few days and then dropped development for a few days only to start showing development again, a lot of the same people who are writing 99L off had written 97L off also. Another thing of interest I saw was that the ensembles continued to show development even when the deterministic models had dropped development....just food for thought.

Not totally writing off 99L yet, even I think the GFS is doing possibly what it did just before Earl formed. Heck the GFS may never show this developing again until a plane gets in there and we get data put into the models from it.

[WeatherEmperor]

Alright so the models shifted a bit north of Hispanola but the margin of error is very small. If the models are 50-75 miles or so off it could mean death over the islands. Unlike Earl which had no land interaction during formative stage so yes it should not be a big surprise the models went from nothing to something. Having said that I cannot ignore the Ensembles and the various intensity models which call for a hurricane. Its a tough forecast

[gatorcane]

I took a close look at the GFS and the environment certainly looks favorable for development should it avoid land interaction. The GFS shows a good vorticity, an upper-anticyclone that moves in tandem with the vorticity, less dry air issues and actually quite a moist environment once it gets to around the Puerto Rico / Lesser Antilles area and especially once in the SE Bahamas area. I can't see why it wouldn't make this stronger in the SE Bahamas on that run or even the previous runs today.

Remember that both the GFS and ECMWF took big upgrades in the off season. I wonder what older ECMWF and GFS models from last year or earlier would show in this scenario? Does the NHC have access to older model SW I wonder? I wonder if in some future model runs, we see these models start bringing the idea of a decent TS or hurricane in their runs.

[Blown Away]

I took a close look at the GFS and the environment certainly looks favorable for development should it avoid land interaction. The GFS shows a good vorticity, an upper-anticyclone that moves in tandem with the vorticity, less dry air issues and actually quite a moist environment once it gets to around the Puerto Rico / Lesser Antilles area and especially once in the SE Bahamas area. I can't see why it wouldn't make this stronger in the SE Bahamas on that run or even the previous runs today.

Remember that both the GFS and ECMWF took big upgrades in the off season. I wonder what older ECMWF and GFS models from last year or earlier would show in this scenario? Does the NHC have access to older model SW I wonder? I wonder if in some future model runs, we see these models start bringing the idea of a decent TS or hurricane in their runs.

The model guidance shifted N of Hispaniola and 99L is showing some popcorn life this evening... So maybe we will see some life in the 00z GFS???

[Bocadude85]

I took a close look at the GFS and the environment certainly looks favorable for development should it avoid land interaction. The GFS shows a good vorticity, an upper-anticyclone that moves in tandem with the vorticity, less dry air issues and actually quite a moist environment once it gets to around the Puerto Rico / Lesser Antilles area and especially once in the SE Bahamas area. I can't see why it wouldn't make this stronger in the SE Bahamas on that run or even the previous runs today.

Remember that both the GFS and ECMWF took big upgrades in the off season. I wonder what older ECMWF and GFS models from last year or earlier would show in this scenario? Does the NHC have access to older model SW I wonder? I wonder if in some future model runs, we see these models start bringing the idea of a decent TS or hurricane in their runs.

I agree. I'm thinking the models start showing development again in a few days once 99L is in the vicinity of the Leeward Islands.

[AJC3]

Without getting into the scientific nuts and bolts, here is a 50-cent explanation of terms...

vorticity is a meteorological parameter, a measure of storm-relative cyclonic spin.
vort, vortex, or vortmax all refer to a localized center of maximum storm relative cyclonic spin (vorticity).
vortices is the plural of vortex.
vortice and vorticy are words that don't exist.


Carry on..

Post resurrection for informational/educational refresher purposes.

Carry on (again)

[Javlin]

None of the models saw Katrina becoming what she diid this far out,just saying.

She came across as a sleeerp once she left TD10 status.I am watching 99L just from past experience's when they blossom early in the MDR they like to be fish I would bet 50/50.I think Ivan was one of the few that made the track as a cane at a low lat. all the way then turned.

[WeatherEmperor]

00z Gfs barely has a closed low approaching the islands at 72hrs. Bit weaker than 18z

[Bocadude85]

00z Gfs barely has a closed low approaching the islands at 72hrs. Bit weaker than 18z

Open wave as it moves through the islands, vort looks to strengthen at 102hours as it approaches Puerto Rico

[Blown Away]

If 00z GFS is a dud, NHC likely to begin backing off development percentages...

[Bocadude85]

Vort is north of Puerto Rico at 108 hours instead of south like on the 18Z

[USTropics]

main vorticity on the northern coast of PR at 108 hours:

[Bocadude85]

Stronger at 126 hours in the SE Bahamas compared to the 18Z

[tarheelprogrammer]

Well Fiona mixing with this system will not be a problem this run.

[USTropics]

No interaction with Hispaniola on this run:

[tarheelprogrammer]

No interaction with Hispaniola on this run:

Two pluses in its favor so far compared with the previous run.

[Hurricaneman]

My feeling is this will be Hermine and wouldn't be surprised if this does something in 5 days around the Turks and Caicos like the GFS and Euro are pointing out

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[Siker]

Getting sheared by Fiona on this run.