ATL: IRMA - Models

[Raebie]

UK Plot



16.7, -57.7
17.2, -60.2
17.9, -63.0
18.9, -65.4
19.8, -68.0
20.6, -70.7
20.9, -73.1
20.9, -75.2
21.0, -77.2
21.2, -78.7
22.2, -79.7
23.5, -79.6
25.5, -79.5

Map tool: https://www.darrinward.com/lat-long/?id=59aed24b454f67.43185594

I just can't see it going that far south and then taking such a sharp turn north. Guess we'll see.

[Steve]

CMC at 120 hours is at about 83.75 west. That's right on the edge of the NW Tip of Cuba. That's as far west as I've seen anything other than the swaths of moisture from the Climate Model (CFSV2) that ran yesterday showing the heaviest rain running from Apalachicola up through Tallahassee. I'm one that never really thought this would go into the Gulf unless it was a brief run through the Keys. I'm less sure today.

[Blown Away]

12z Canadian model takes Irma into the Gulf!

Yes, but 12z a decent E shift from 00z...

[ColdMiser123]

No choice but to bend N to NNW at the end of the 12z UKMET.

[txwatcher91]

CMC at 120 hours is at about 83.75 west. That's right on the edge of the NW Tip of Cuba. That's as far west as I've seen anything other than the swaths of moisture from the Climate Model (CFSV2) that ran yesterday showing the heaviest rain running from Apalachicola up through Tallahassee. I'm one that never really thought this would go into the Gulf unless it was a brief run through the Keys. I'm less sure today.

CMC is a terrible model for forecasting TC track. If the Euro comes in similar to GFS and UK then I wouldn’t put much stock into it at all. Plus, it did shift east from its prior run.

[tolakram]

CMC at 120 hours is at about 83.75 west. That's right on the edge of the NW Tip of Cuba. That's as far west as I've seen anything other than the swaths of moisture from the Climate Model (CFSV2) that ran yesterday showing the heaviest rain running from Apalachicola up through Tallahassee. I'm one that never really thought this would go into the Gulf unless it was a brief run through the Keys. I'm less sure today.

CMC is a terrible model for forecasting TC track. If the Euro comes in similar to GFS and UK then I wouldn’t put much stock into it at all. Plus, it did shift east from its prior run.

Steve knows, but you can use it as a trend setter. If the upper air changes the track will change. it will still be wrong, just different wrong.

[Bocadude85]

It's riding the coast, looks like it'll come on shore right at the GA/SC border. SC is part of the Carolinas, and they will experience a significant hurricane from this path. This is also the second east shift in a row. Needs to be watched.

This run shifted west by a good amount near GA. Only difference was that FL dodged complete landfall by a few miles.

East and West is relative. The overall track shifted east away from Florida, which had effects further down the line when it made it's left turn.

The GFS did not shift away from Florida, people need to stop -removed- this storm to their area. GFS continues to show a significant threat to Florida. The models will continue to shift east and west. We saw these small shifts even in the three day forecast as Irma was approaching the Leewards. The GFS was consistently to far north and east with Irma even in the short range.

[Steve]

CMC at 120 hours is at about 83.75 west. That's right on the edge of the NW Tip of Cuba. That's as far west as I've seen anything other than the swaths of moisture from the Climate Model (CFSV2) that ran yesterday showing the heaviest rain running from Apalachicola up through Tallahassee. I'm one that never really thought this would go into the Gulf unless it was a brief run through the Keys. I'm less sure today.

CMC is a terrible model for forecasting TC track. If the Euro comes in similar to GFS and UK then I wouldn’t put much stock into it at all. Plus, it did shift east from its prior run.

I've been running it for 20+ years. It was #2 for a while with IRMA behind HWRF. It's a model. It's the model thread. NHC often uses it and defers to it. It often sucks too and completely botches a solution. However, it's not been all that terrible since the upgrade last year. Also, it's the model thread and it is currently running. Its track is closer to the NHC's track than the current GFS. I'm not suggesting anyone rely on the CMC for life and death decisions. I'm reporting what it shows on the run.

[Steve]

FWIW, CMC landfalls around Apalachicola at 168 hours 970. I'm not suggesting this is a valid track any more than I'm suggesting UKMET, ECMWF or GFS are. I go with the NHC usually.

[ronjon]

12z Canadian model takes Irma into the Gulf!

Yes, but 12z a decent E shift from 00z...

Gems short wave is slower and further west than 12z GFS - its in southern Arkansas at 120 hrs when GFS has its in south Alabama. GEM shortwave then drops south into northern La similar to this mornings Euro run. Will be interesting which side the Euro model comes down on in this afternoons run.

https://www.tropicaltidbits.com/analysis/models/?model=gem&region=seus&pkg=z500_vort&runtime=2017090512&fh=126&xpos=0&ypos=110

[Vdogg]

This run shifted west by a good amount near GA. Only difference was that FL dodged complete landfall by a few miles.

East and West is relative. The overall track shifted east away from Florida, which had effects further down the line when it made it's left turn.

The GFS did not shift away from Florida, people need to stop -removed- this storm to their area. GFS continues to show a significant threat to Florida. The models will continue to shift east and west. We saw these small shifts even in the three day forecast as Irma was approaching the Leewards. The GFS was consistently to far north and east with Irma even in the short range.

The GFS had landfall down the spine of Florida, now it has the Western eyewall grazing eastern Florida. It is, quite simply, a fact that the model is east of the previous run where Florida is involved. There is no -removed- here, use your eyes. I made no statement as to the effects that the Western eyewall will have on Eastern Florida, I imagine it will be quite intense.

[Steve]

HWRF crosses 20N between hours 36 and 39 on a WNW heading.

36 hours (7pm tomorrow) - 19.9N 66.2W @ 914mb
39 hours (10pm tomorrow) - 20.1N 67.15W @ 918mb

It's still a Cat 5 tomorrow per HWRF.
https://www.tropicaltidbits.com/analysi ... 0512&fh=36

[bqknight]

12z HWRF is running, track appears to be similar through 39 hours. Difference is it has the storm as stronger. 914mb and 185 kts (210mph). Although that would be crazy, I've seen it said that the HWRF is one of the better intensity models the NHC has.

[MatthewsRevenge]

GFS doesn't have it escaping Florida. UKMet kinda does but then again, you can't judge from a tracking.

[Bocadude85]

I'm not sure if this belongs in the model thread or the discussion thread but one thing to watch for is if Irma gets west of Andros Island in the Bahamas. I can not find any hurricanes that passed west of Andros on Irmas forecast trajectory that missed Florida to the east.

[Steve]

12z HWRF is running, track appears to be similar through 39 hours. Difference is it has the storm as stronger. 914mb and 185 kts (210mph). Although that would be crazy, I've seen it said that the HWRF is one of the better intensity models the NHC has.

It was also just behind the NHC on the short term track on Saturday or Sunday the last time someone found and posted the verifications. I'm not suggesting the HWRF should be used for decisions either. I personally have hated it for so long, it's taking a long time to warm up to the fact that it may be better these days. Scary big ticket storm. It squeezed between Cuba and FL last run I saw which I think was the 00Z run following 2 runs where it hit Cuba and got disrupted a bit. I didn't look at the 06Z to see what that did yet. Edit to say I just went back and looked at it, and it did not hit Cuba at 06Z.

[Extratropical94]

12z HWRF is running, track appears to be similar through 39 hours. Difference is it has the storm as stronger. 914mb and 185 kts (210mph). Although that would be crazy, I've seen it said that the HWRF is one of the better intensity models the NHC has.

I believe that's at 850 mb. 10m winds are around 140-150 knots.

[chris_fit]

The 12Z HWRF is running now - For reference here is where the 6Z run ended up, still moving NW/NNW

[txwatcher91]

CMC at 120 hours is at about 83.75 west. That's right on the edge of the NW Tip of Cuba. That's as far west as I've seen anything other than the swaths of moisture from the Climate Model (CFSV2) that ran yesterday showing the heaviest rain running from Apalachicola up through Tallahassee. I'm one that never really thought this would go into the Gulf unless it was a brief run through the Keys. I'm less sure today.

CMC is a terrible model for forecasting TC track. If the Euro comes in similar to GFS and UK then I wouldn’t put much stock into it at all. Plus, it did shift east from its prior run.

I've been running it for 20+ years. It was #2 for a while with IRMA behind HWRF. It's a model. It's the model thread. NHC often uses it and defers to it. It often sucks too and completely botches a solution. However, it's not been all that terrible since the upgrade last year. Also, it's the model thread and it is currently running. Its track is closer to the NHC's track than the current GFS. I'm not suggesting anyone rely on the CMC for life and death decisions. I'm reporting what it shows on the run.

I certainly understand, I’ve been running it 20 years myself. Yes it is useful for observing trends and worth mentioning for that reason alone, but it has performed horribly this year and many new people who read this and see that it hits the FL panhandle may not understand that.

[Bocadude85]

12z HWRF is running, track appears to be similar through 39 hours. Difference is it has the storm as stronger. 914mb and 185 kts (210mph). Although that would be crazy, I've seen it said that the HWRF is one of the better intensity models the NHC has.

It was also just behind the NHC on the short term track on Saturday or Sunday the last time someone found and posted the verifications. I'm not suggesting the HWRF should be used for decisions either. I personally have hated it for so long, it's taking a long time to warm up to the fact that it may be better these days. Scary big ticket storm. It squeezed between Cuba and FL last run I saw which I think was the 00Z run following 2 runs where it hit Cuba and got disrupted a bit. I didn't look at the 06Z to see what that did yet. Edit to say I just went back and looked at it, and it did not hit Cuba at 06Z.

The 6Z HWRF has landfall in the middle Fla Keys.