ATL: IRMA - Models

[bonjourno]

18Z HWRF run

I've heard it's supposedly bad to follow the HWRF-P for some reason. Any truth to that?

[Canelaw99]

Does anyone have an updated graphic showing how well the models are performing so far? I've seen it over the last couple days, but not today, and it might be relevant at this point in the discussion. Thanks!

[tolakram]

18Z HWRF run
[im g]https://i.imgur.com/cDvnkDP.gif[/img]

I've heard it's supposedly bad to follow the HWRF-P for some reason. Any truth to that?

Depends, I use it so you can follow the storm and the MSLP. It should not be used for upper air or anything else AFAIK, it's just a way to better visualize the track.

[Bocadude85]

The energy that will cause this to make the turn is inside 84 hours and becoming better modeled. The east coast of FL is the most likely track imo, a Floyd analog looks very reasonable here still. When you have an excellent model like the NAM inside 48 hours that’s showing such a weak finger ridge... and then models start to trend towards that, it’s something to take note of and consider. The NAM is excellent at picking up patterns and changes inside 48 hours that other models simply miss or play catch up on.

Those questioning the hard right turn haven’t seen and experienced past hurricanes that did. It can, and does, happen if the pattern supports it. All models agree on the north turn it’s just a matter of how long before that happens.

How do you explain the 18Z GFS ensemble mean that is significantly west of the OP run? When the ensembles don't agree with the op run that is usually a clue that there is something funky. Go through the GFS ensembles since 12z this morning..they have all be west of the op run. The NHC doesn't base their forecast off one model..they have other models available to them that are not available to the public.

Ensemble means are great tools outside 120 hours but OP runs are a little better inside that mark, imo. The Euro was way west of its ensemble mean, as well, so by the same reasoning it should be discounted Yes the ensembles are west of the OP for the GFS but that doesn’t necessarily mean it’s right, or wrong. I’ve seen many of these storms over the years that are forecast to make a hard right turn and usually it occurs faster and sooner than anticipated. Also, I explained why the OP run has added weight since the NAM synoptic setup concurs with the GFS and the 18z HWRF also made a significant north shift through most of its run to match that also. There is plenty of time for further adjustments but the east of Florida track is what I’ve thought would happen all along and I’m sticking with it, along with my Floyd 99 analog.

Well all I can say is if Irma passes west of Andros Island (which nearly every model shows) and still misses Florida to the east then it will be a first, I still can not find one past hurricane that passed west of Andros coming from the east or southeast that missed Florida to the east.

[Ken711]

The energy that will cause this to make the turn is inside 84 hours and becoming better modeled. The east coast of FL is the most likely track imo, a Floyd analog looks very reasonable here still. When you have an excellent model like the NAM inside 48 hours that’s showing such a weak finger ridge... and then models start to trend towards that, it’s something to take note of and consider. The NAM is excellent at picking up patterns and changes inside 48 hours that other models simply miss or play catch up on.

Those questioning the hard right turn haven’t seen and experienced past hurricanes that did. It can, and does, happen if the pattern supports it. All models agree on the north turn it’s just a matter of how long before that happens.

How do you explain the 18Z GFS ensemble mean that is significantly west of the OP run? When the ensembles don't agree with the op run that is usually a clue that there is something funky. Go through the GFS ensembles since 12z this morning..they have all be west of the op run. The NHC doesn't base their forecast off one model..they have other models available to them that are not available to the public.

Ensemble means are great tools outside 120 hours but OP runs are a little better inside that mark, imo. The Euro was way west of its ensemble mean, as well, so by the same reasoning it should be discounted Yes the ensembles are west of the OP for the GFS but that doesn’t necessarily mean it’s right, or wrong. I’ve seen many of these storms over the years that are forecast to make a hard right turn and usually it occurs faster and sooner than anticipated. Also, I explained why the OP run has added weight since the NAM synoptic setup concurs with the GFS and the 18z HWRF also made a significant north shift through most of its run to match that also. There is plenty of time for further adjustments but the east of Florida track is what I’ve thought would happen all along and I’m sticking with it, along with my Floyd 99 analog.

Floyd track is certainly possible.

[Dean4Storms]

Does anyone have an updated graphic showing how well the models are performing so far? I've seen it over the last couple days, but not today, and it might be relevant at this point in the discussion. Thanks!

It was posted a few pages back.....ECM led the way among them all @ 5 days about 100KM error
GFS @ 5 days about 500km

[RL3AO]

Ensemble means are great tools outside 120 hours but OP runs are a little better inside that mark, imo.

Do you have a scientific reason to make such a statement?

[txwatcher91]

Does anyone have an updated graphic showing how well the models are performing so far? I've seen it over the last couple days, but not today, and it might be relevant at this point in the discussion. Thanks!

I saw one earlier today indicating the Euro was best, UK second. However the Euro and UK disagree quite a bit with how soon the turn happens and the point at which this turns is well within the NHC come and margin for error of even the Euro.

[txwatcher91]

Ensemble means are great tools outside 120 hours but OP runs are a little better inside that mark, imo.

Do you have a scientific reason to make such a statement?

Experience from watching, reading, and learning from some of the best local pro mets we have and others who I’ve talked to. When I visited our local NWS office, one of the mets there was talking about why he uses ensemble means outside 120 hours and then prefers a blend of the OP runs inside 120. Not everyone prefers this method but it’s worked well for me over the years and quite a few pro mets/veteran forecasters I know.

[Steve]

Well us here along the NGOM are forecast to have lows in the 60's till Monday and I mean 61'62' if this happens I cannot see Irma getting that far in the GOM.

Literally no chance whatsoever. Maybe if you were in Alligator Pointe or Carabelle, maybe you wonder. AL? MS? LA? Not this time

[Hurricane Andrew]

Not sure why the HWRF weakens it right away.

[SFLcane]

00z runs still clustered over SFL..

[caneman]

The energy that will cause this to make the turn is inside 84 hours and becoming better modeled. The east coast of FL is the most likely track imo, a Floyd analog looks very reasonable here still. When you have an excellent model like the NAM inside 48 hours that’s showing such a weak finger ridge... and then models start to trend towards that, it’s something to take note of and consider. The NAM is excellent at picking up patterns and changes inside 48 hours that other models simply miss or play catch up on.

Those questioning the hard right turn haven’t seen and experienced past hurricanes that did. It can, and does, happen if the pattern supports it. All models agree on the north turn it’s just a matter of how long before that happens.

How do you explain the 18Z GFS ensemble mean that is significantly west of the OP run? When the ensembles don't agree with the op run that is usually a clue that there is something funky. Go through the GFS ensembles since 12z this morning..they have all be west of the op run. The NHC doesn't base their forecast off one model..they have other models available to them that are not available to the public.

Ensemble means are great tools outside 120 hours but OP runs are a little better inside that mark, imo. The Euro was way west of its ensemble mean, as well, so by the same reasoning it should be discounted Yes the ensembles are west of the OP for the GFS but that doesn’t necessarily mean it’s right, or wrong. I’ve seen many of these storms over the years that are forecast to make a hard right turn and usually it occurs faster and sooner than anticipated. Also, I explained why the OP run has added weight since the NAM synoptic setup concurs with the GFS and the 18z HWRF also made a significant north shift through most of its run to match that also. There is plenty of time for further adjustments but the east of Florida track is what I’ve thought would happen all along and I’m sticking with it, along with my Floyd 99 analog.

Not buying it. My understanding has always been to go with the ensembles. Further, 48 hours out on the NAM isn't far enough out. I'll go with up the spine of Florida. The Euro UKMET and TVCN had been most accurate a couple days ago but the UKIE seems to have gone wonky. So a split between Euro And TVCN seems reasonable.

[johngaltfla]

Edit..first post, wrong thread.

I'm going to agree with Bastardi for once and dismiss the last GFS run as an anomaly. I want to see the runs with the 0500 advisory to see what the trend is. That will be more important.

Please folks, do not rely on the models for decisions of your own safety. If you do not feel it is good to ride this out, get out.

[MatthewsRevenge]

Looks like 00z is kinda backing away from this storm curving out of FL now but no clue where it will go. Guess it's waiting on Euro and GFS. Interesting to note that Alan is disregarding's GFS' 18z run... and he could very well be right. Like I said earlier, I think GFS overdid the performance of the shortwave supposedly coming. And I supposed GFS also expected a trough to pull through on that last run too. Hence why it went NE like that very sharply.

[PandaCitrus]

There are many, many model tracks that would be bad for Florida and scare me. #1 Worst is the I-95 track.

It was the GFS track from yesterday that was a direct hit on Key Largo and the eye went up the western suburbs of Miami so the core northeast eyewall bulldozed Miami-Dade, Broward, Palm Beach, Martin, St. Lucie counties as the eye approached Lake Okeechobee. It then went toward Orlando and up towards Jacksonville. That's probably a $1 Trillion catastrophe and the economy and how the State functions might never be the same.

The I-75 Euro track this afternoon is probably the second worst I saw. It would cause major, major, major problems in Naples, Ft. Myers, Sarasota, Tampa, Ocala, Gainesville, and Jacksonville. There are so many trailers and manufactured housing in Central Florida that would be very suspect in Category 1 winds.

The HWRF track straight up the spine of Florida might be the best of the worst options if hitting Florida is unavoidable. It would concentrate the maximum winds in the least populated areas (Everglades and agricultural counties) but would still be bad. Both Southwest and Southeast Florida would probably get Cat 2/3 winds and there would be major problems up in the Orlando area.

[johngaltfla]

Looks like 00z is kinda backing away from this storm curving out of FL now but no clue where it will go. Guess it's waiting on Euro and GFS. Interesting to note that Alan is disregarding's GFS' 18z run... and he could very well be right. Like I said earlier, I think GFS overdid the performance of the shortwave supposedly coming. And I supposed GFS also expected a trough to pull through on that last run too. Hence why it went NE like that very sharply.

IF the models and storm confirm the storm passing 78 degrees west without a sharp N-NNW turn, time to get worried.

[yzerfan]

Well us here along the NGOM are forecast to have lows in the 60's till Monday and I mean 61'62' if this happens I cannot see Irma getting that far in the GOM.

Granted, it was about a month earlier during the season, but one thing I remember about Charley was how those of us in the western Florida Panhandle were having a freak 'cold front' as the storm was heading toward the peninsula and it was utterly freaky to be seeing dew points in the low 60s in August.

Those kind of lows here and now have the recurve making more sense to me.

[bamajammer4eva]

Model margin of error and direction of error. I noted the GFS/AVN, Euro, and Official forecast




http://www.atmos.albany.edu/facstaff/tang/tcguidance/

[Miami Storm Tracker]

My apologies to the Mod's just realized I am in the models thread ,pease delete if need be.