ATL: IRMA - Models

[MrJames]

CMC landfall in S FL but shifts track east with a second hit in NC

[p1nheadlarry]

I'll ask again since it was a few pages ago.. anyone know if the balloon data from across the CONUS was included in this GFS run?

All of the normal 12Z data from the CONUS radiosondes has been assimilated into this model suite. Six hour radiosonde launches haven't begun quite yet.

From latest FD:

Six hourly upper-air soundings will begin at 1800 UTC today over the
central United States to better sample the upstream mid-latitude
trough. In addition, the NOAA G-IV aircraft will begin sampling the
environment around Irma this afternoon and evening, and these data
will be included in tonight's 0000 UTC model runs.

[JPmia]

https://weather.us/model-charts/standard/broward/windspeed-barbs/20170910-2100z.html

https://weather.us/model-charts/standard/florida/windspeed-barbs/20170911-0000z.html

So the latest GFS would do this to SE FL.. it's pure model fantasy, but quite interesting to look at.

[pcolaman]

models are still betting some sort of a low to develop over the MS valley... not buying into it yet..

I don't see it either ? There's really not much coming from the nw atm

[psyclone]

Not buying the brick wall turn

You don't have to buy it but nature often sells it. Matthew and Hermine last year both made abrupt turns. It's fairly common.

[Vdogg]

No sharp NE turn this run. Trend is bad for the GOM

Disagree, this is not bad at all for the GOM ... this run doesn't even make the GOM... how can this be bad?

It's the trends. We've gone further west each run, and more ensemble members are making it into the north/east gulf since Friday.

But it went further north and east this run.

[CrazyC83]

CMC landfall in S FL but shifts track east with a second hit in NC

In other words, a reincarnation almost perfectly of Donna.

[xtyphooncyclonex]

I'd not be surprised to see potential runs shifting to a track similar to Donna 1960

Found this 103 pages back (Page 184)

[Aric Dunn]

Not buying the brick wall turn

You don't have to buy it but nature often sells it. Matthew and Hermine last year both made abrupt turns. It's fairly common.

Downstream features that have not deveoped yet are terribly tricky to forecast. IF that low does not develop than no sharp north turn..

[pcolaman]

Disagree, this is not bad at all for the GOM ... this run doesn't even make the GOM... how can this be bad?

It's the trends. We've gone further west each run, and more ensemble members are making it into the north/east gulf since Friday.

But it went further north and east this run.

About 50 to 75 mile more north but not as far east easy earlier runs .

[stormreader]

CMC landfall in S FL but shifts track east with a second hit in NC

In other words, a reincarnation almost perfectly of Donna.

What I always liked about the Donna analog was the fact that it formed at almost the exact same date (Aug 29) in the Cabo Verde Islands area. Donna did not intensify quite as quickly as Irma, but still was a major hurricane well out to sea. Donna peaked at Cat 4 before entering the Keys and turning up into Fl and then paralleling the East seaboard. The similarities are obviously there.

[xtyphooncyclonex]

But it went further north and east this run.

The trends are no good for Florida, because avoiding landfall over Cuba's mountains means less weakening and a stronger storm. Trough doesn't penetrate as deep as well

[Dean4Storms]

Peeps, one or two runs on a hurricane still 5-6 days out can still swing one way or the other. Yes Florida, Gulf, Atlantic and even NC/SC are all still in play! Everyone breathe!

[Steve]

GFS now makes its west hook around Pittsburgh and moves across Lake Erie into southern Ontario and loops back to Buffalo, NY on the way out. Worst weather on the second landfall is in South Carolina. As the system moves up from there, the worst weather is east across North Carolina as the center crosses just east of the Smokys, West Virginia, PA, Ontario.

[RL3AO]

models are still betting some sort of a low to develop over the MS valley... not buying into it yet..

I don't see it either ? There's really not much coming from the nw atm

It's subtle but it's there. Shortwave troughs going trough a longwave ridge get lost since the relative vorticity of the shortwave gets lost in the negative vorticity of the ridge.

[Vdogg]

CMC landfall in S FL but shifts track east with a second hit in NC

So gfs and CMC move east to a Carolinas hit. Euro comes back from OTS to a Carolinas hit. Maybe, just maybe, we're dialing in on some sort of consensus. Ensembles should be interesting.

[Hurricane Andrew]

CMC landfall in S FL but shifts track east with a second hit in NC

Then says hi to me...

[otowntiger]

The very subtle shortwave trough near Missouri could make a big impact in when Irma turns.

[image removed]

That's currently over NE/SD right?

Looks like that feature is currently off the Pacific coast. It moves north into British Colombia and then dives southeast behind the main trough. It's a subtle feature, so it's hard to track unless you know what you're looking for.

in 'looking at this clip, look at the high pressure retro grading significantly allowing Jose -to -be to go north out to sea could be enough to allow Irma to start turning north sooner- maybe?? Hopefully??

[Weatherboy1]

Absolute worst case scenario for Florida, and the models have been consolidating on this solution for a while. Florida impacts would be 5+ days out, plenty of time for the outlook to change. Still, the kind of preparations needed for a threat this potentially devastating need to start right now.

Yeah, being a South Floridian my entire life, I can second this. If this were to verify, it has the potential to be the most expensive hurricane in US history. Thankfully we are still 6 days out (give or take), and a lot can change in terms of strength, path, etc. But now is definitley the time to do some preparations, get some supplies, and have a plan ready.

[Vdogg]

CMC landfall in S FL but shifts track east with a second hit in NC

So gfs and CMC move east to a Carolinas hit. Euro comes back from OTS to a Carolinas hit. Maybe, just maybe, we're dialing in on some sort of consensus. Ensembles should be interesting.

Isn't that, literally, the exact path of Donna?