ATL: IRMA - Models

[AdamFirst]

Can a pro met splain how the 1-3 day track atmosphere ahead of Irma, that's likely already being well modeled, is going dramatically change the path?

It's likely much more helpful for the 3-5 day track (and beyond). The current NHC track at Day 5 is right around the potential place of a northerly turn.

[FireRat]

Thanks for the Ike track image RL3AO, it was more like 4 days prior to the storm being in south FL, sure felt like it was sooner due to all t he Ike coverage on the news. This then would mean that by tomorrow, Sept 5, FL will know for sure if it will get a strong hurricane impact. So many "wolf cries" and near misses in the past. I'm afraid many won't take Irma seriously in the Miami area.

[sma10]

Like the old saying goes when you're in the bulls eye this far out then more than likely you're okay. I would be more concerned if we are seeing the same thing on Wed. Too much can change before then. I still don't think the East coast or Gulf are even remotely out of the woods.

This is actually a bit of a truism. Some people think that when people shout, "hey im bullseyed at 5 days - I'm safe" are just whistling past the graveyard. But the truth is, look at the archived records of model performances. Show me a model that ever had a 5 day error of 0 miles. Dont get me wrong, im NOT saying that if you are in the cross hairs at 5 days you should ignore preparing for the storm. But the fact is you are extremely unlikely to get the core.

Extremely unlikely? I don't think so. It'll change slightly but this isn't 2003 where it'll shift to Texas or Maine. The models have performed just fine with this storm 5 days out with Irma still on track near the islands. Keep in mind that the data comes in with the 00z models. If they continue to show FL, it is time to prepare.

I agree with you that you should prepare, and said so in my post.

And in no way did i mean to suggest that this would change track to maine or texas. I was simply making a statistical argument regarding the center, or core of the storm.

Look, if this storm rides due north up 79W, this would be an OUTSTANDING 5 day modeled forecast. And would there be some wild dangerous weather for the Florida peninsula? Of course. But it won't be the same impact as the currently modeled ride up 80W.

I was simply making an academic case, but perhaps this isn't the time to do this.

[CrazyC83]

Like the old saying goes when you're in the bulls eye this far out then more than likely you're okay. I would be more concerned if we are seeing the same thing on Wed. Too much can change before then. I still don't think the East coast or Gulf are even remotely out of the woods.

South FL is now in the cone. The "GFS hits us in 12 days so we'll be okay" doesn't really seem to apply here. I hope people don't wait until Wednesday to start preparing.

the old timers are acting like it was 25 years ago when a 3 day forecast was unreliable. The reality today is that a 5 day forecast is about as reliable as a 36 hour forecast was then. Very unlikely to bomb completely with this synoptic setup less than 5 days. It takes a Joaquin to cause a total bust these days

Joaquin was only a total bust because the synoptic setup was extremely sensitive to small pieces - only a slight change would have messed the whole situation up.

[Steve]

Like the old saying goes when you're in the bulls eye this far out then more than likely you're okay. I would be more concerned if we are seeing the same thing on Wed. Too much can change before then. I still don't think the East coast or Gulf are even remotely out of the woods.

South FL is now in the cone. The "GFS hits us in 12 days so we'll be okay" doesn't really seem to apply here. I hope people don't wait until Wednesday to start preparing.

Everyone in sofla needs to.prepare, this system.is different, it will have a large windfield and intense, prepare for a major hit and hope we get off easy...i know we like to be in the crosshairs this far out but even 150 miles to the north and east will.have substantial weather..the modeling is more troubling than ever with it off the north cuban coast coming through the straits

Yeah. Hey JL. I've known you since what, 96 or 97? You are so right. Harvey RI'd and got to 4, but it was a smallish system that hit a lesser populated area as Cat 4. There was immense coastal destruction from that for sure. But it is going down as Top 1 or Top 2 all time with Katrina because of rainfall. Irma on the other hand seems to have potential to structurally wreck more structures with wind and power. It's kind of insane to sit here talking about a deep Category 4 or 5 hitting SFL late this weekend. Granted we don't know for sure 6-7 days out that this absolutely hits Florida. And we certainly don't know where it hits if it does. But this is as bad of anything that we have anticipated in a decade. I have a house in Florida too, so my heart and love goes out to all of you all. I always thought we'd know what was going to be up by tomorrow, but most of the solutions are pretty close earlier. I'm kind of scared to run the new NAM's that are out. And GFS is 80 minutes out. I hope something breaks, but from here in New Orleans, I rate the potential of Irma as like a 9 on the 10 scale.

[facemane]

Like the old saying goes when you're in the bulls eye this far out then more than likely you're okay. I would be more concerned if we are seeing the same thing on Wed. Too much can change before then. I still don't think the East coast or Gulf are even remotely out of the woods.

South FL is now in the cone. The "GFS hits us in 12 days so we'll be okay" doesn't really seem to apply here. I hope people don't wait until Wednesday to start preparing.

the old timers are acting like it was 25 years ago when a 3 day forecast was unreliable. The reality today is that a 5 day forecast is about as reliable as a 36 hour forecast was then. Very unlikely to bomb completely with this synoptic setup less than 5 days. It takes a Joaquin to cause a total bust these days

I was looking for an image and was unable to find it. If anyone can help, I'd appreciate it. It was the 5 day cone for Hurricane Andrew in 1992 vs what would have been the cone today. The difference was drastic. IIRC, the 5 day cone in 1992 had Andrew hitting anywhere from Cuba to the Carolinas. The 5 day cone today
narrowed it from the Florida straits to central Fla. The science is definitely improving the performance of these models.

[Langinbang187]

I believe we shall see alittle more westward shift before final destination.

If it gets too far west Cuba may very well put a serious beating on it.

[drewschmaltz]

South FL is now in the cone. The "GFS hits us in 12 days so we'll be okay" doesn't really seem to apply here. I hope people don't wait until Wednesday to start preparing.

the old timers are acting like it was 25 years ago when a 3 day forecast was unreliable. The reality today is that a 5 day forecast is about as reliable as a 36 hour forecast was then. Very unlikely to bomb completely with this synoptic setup less than 5 days. It takes a Joaquin to cause a total bust these days

I was looking for an image and was unable to find it. If anyone can help, I'd appreciate it. It was the 5 day cone for Hurricane Andrew in 1992 vs what would have been the cone today. The difference was drastic. IIRC, the 5 day cone in 1992 had Andrew hitting anywhere from Cuba to the Carolinas. The 5 day cone today
narrowed it from the Florida straits to central Fla. The science is definitely improving the performance of these models.

This is what I was able to turn up: http://abcnews.go.com/US/hurricane-andr ... d=49389188

Check towards the end.

[RL3AO]

I was looking for an image and was unable to find it. If anyone can help, I'd appreciate it. It was the 5 day cone for Hurricane Andrew in 1992 vs what would have been the cone today. The difference was drastic. IIRC, the 5 day cone in 1992 had Andrew hitting anywhere from Cuba to the Carolinas. The 5 day cone today
narrowed it from the Florida straits to central Fla. The science is definitely improving the performance of these models.

Can't remember seeing the Andrew one, but a 5 day forecast now is better than a 3 day forecast then, and a 3 day forecast now is better than 1 day during Andrew's time.

[pcolaman]

I believe we shall see alittle more westward shift before final destination.

If it gets too far west Cuba may very well put a serious beating on it.

Or could do like Ivan and dance around Cuba

[sma10]

South FL is now in the cone. The "GFS hits us in 12 days so we'll be okay" doesn't really seem to apply here. I hope people don't wait until Wednesday to start preparing.

the old timers are acting like it was 25 years ago when a 3 day forecast was unreliable. The reality today is that a 5 day forecast is about as reliable as a 36 hour forecast was then. Very unlikely to bomb completely with this synoptic setup less than 5 days. It takes a Joaquin to cause a total bust these days

I was looking for an image and was unable to find it. If anyone can help, I'd appreciate it. It was the 5 day cone for Hurricane Andrew in 1992 vs what would have been the cone today. The difference was drastic. IIRC, the 5 day cone in 1992 had Andrew hitting anywhere from Cuba to the Carolinas. The 5 day cone today
narrowed it from the Florida straits to central Fla. The science is definitely improving the performance of these models.

Unfortunately, you will never find this because it doesnt exist. The nhc did not release cones back then. They only released data points, similar to what you find in the discussion, and even then they only went out 3 days back then.

Andrew struck at 5am on 8/24/92. If you'd like to read the discussion from exactly 72 hrs prior to landfall:

http://www.nhc.noaa.gov/archive/storm_w ... al0492.018

Edit: I've reread your post and see what you might be asking for. A couple of years ago, the NHC reran Andrew synoptics with modern computing to see how they would perform. I believe though it was less than 72 hrs out though. The performance was much better than 92. I think the consensus from 48hr out was Palm Beach.

[Steve]

Like the old saying goes when you're in the bulls eye this far out then more than likely you're okay. I would be more concerned if we are seeing the same thing on Wed. Too much can change before then. I still don't think the East coast or Gulf are even remotely out of the woods.

South FL is now in the cone. The "GFS hits us in 12 days so we'll be okay" doesn't really seem to apply here. I hope people don't wait until Wednesday to start preparing.

the old timers are acting like it was 25 years ago when a 3 day forecast was unreliable. The reality today is that a 5 day forecast is about as reliable as a 36 hour forecast was then. Very unlikely to bomb completely with this synoptic setup less than 5 days. It takes a Joaquin to cause a total bust these days

Haha. I read that "very unlikely to bomb" wrong at first. I'm actually kind of scared bleep-less for conditions just east of and in the FL Straits. Despite the 930's and 920's and whatever we have for the next few days, it seemed like the 900's or ? came right before it turned up into South Florida. It's not going to hit me, but this **** is bad.

Back to models - the NAM at 39 hours is whipping that deep trough southward through the Ohio Valley. The strong ridge just north of Irma is coming into the picture from the Southeast with a "finger" north of it. Last run lifted out as 99% chance this one will too. High pressure in west-central Canada remains strong at the surface and at 500.
https://www.tropicaltidbits.com/analysi ... 0&ypos=500

[caneseddy]

South FL is now in the cone. The "GFS hits us in 12 days so we'll be okay" doesn't really seem to apply here. I hope people don't wait until Wednesday to start preparing.

the old timers are acting like it was 25 years ago when a 3 day forecast was unreliable. The reality today is that a 5 day forecast is about as reliable as a 36 hour forecast was then. Very unlikely to bomb completely with this synoptic setup less than 5 days. It takes a Joaquin to cause a total bust these days

Haha. I read that "very unlikely to bomb" wrong at first. I'm actually kind of scared bleep-less for conditions just east of and in the FL Straits. Despite the 930's and 920's and whatever we have for the next few days, it seemed like the 900's or ? came right before it turned up into South Florida. It's not going to hit me, but this **** is bad.

Back to models - the NAM at 39 hours is whipping that deep trough southward through the Ohio Valley. The strong ridge just north of Irma is coming into the picture from the Southeast with a "finger" north of it. Last run lifted out as 99% chance this one will too. High pressure in west-central Canada remains strong at the surface and at 500.
https://www.tropicaltidbits.com/analysi ... 0&ypos=500

Does this have the Gulfstream and balloon soundings?

[bamajammer4eva]

My question I had earlier about the 18z GEFS Mean vs plots shown on tropical tidbits. The AEMN plot shows this staying well inland after landfall and going up the spine of FL. The GEFS plots on tropical tidbits show it missing Florida to the west with a landfall in the Big Bend area. What are the plots on tropical tidbits since they must not be the mean,

[catskillfire51]

One thing just comparing things is Hurricane Ike's 5 day cone on Sept 4, 2008 is oddly very similar.

[RL3AO]

My question I had earlier about the 18z GEFS Mean vs plots shown on tropical tidbits. The AEMN plot shows this staying well inland after landfall and going up the spine of FL. The GEFS plots on tropical tidbits show it missing Florida to the west with a landfall in the Big Bend area. What are the plots on tropical tidbits since they must not be the mean,

I think the difference is the top one is a track mean, while the Tropical Tidbits graphic is a pressure mean. The GEFS has stronger storms in the EGOM vs East Coast which puts the pressure mean in the EGOM, but the track mean over Florida.

[Steve]

It should have some. Earlier it was explained that the balloons are almost in real time now. And the Gulf Stream sampling is supposed to be in the 00Z runs. Nam will be close to right on the continent 2-3 days. I'm looking for hints or surprises.

So this is odd on the 00Z NAM 39 hours 700 geo height, cyclonic vorticity and wind:
https://www.tropicaltidbits.com/analysi ... 0&ypos=500

Mid-level energy from the WPAC storm goes up the CA Coast, low spins up in the BoC and the Atlantic High is nosing in over the top of Irma not letting her turn up.

Edit --> Meant this link: https://www.tropicaltidbits.com/analysi ... 0&ypos=327

[nascarfan999]

the old timers are acting like it was 25 years ago when a 3 day forecast was unreliable. The reality today is that a 5 day forecast is about as reliable as a 36 hour forecast was then. Very unlikely to bomb completely with this synoptic setup less than 5 days. It takes a Joaquin to cause a total bust these days

I was looking for an image and was unable to find it. If anyone can help, I'd appreciate it. It was the 5 day cone for Hurricane Andrew in 1992 vs what would have been the cone today. The difference was drastic. IIRC, the 5 day cone in 1992 had Andrew hitting anywhere from Cuba to the Carolinas. The 5 day cone today
narrowed it from the Florida straits to central Fla. The science is definitely improving the performance of these models.

Unfortunately, you will never find this because it doesnt exist. The nhc did not release cones back then. They only released data points, similar to what you find in the discussion, and even then they only went out 3 days back then.

Andrew struck at 5am on 8/24/92. If you'd like to read the discussion from exactly 72 hrs prior to landfall:

http://www.nhc.noaa.gov/archive/storm_w ... al0492.018

Edit: I've reread your post and see what you might be asking for. A couple of years ago, the NHC reran Andrew synoptics with modern computing to see how they would perform. I believe though it was less than 72 hrs out though. The performance was much better than 92. I think the consensus from 48hr out was Palm Beach.

In addition to the actual advisory above, there is also the below which listed probabilities of the center passing within 65 miles of a given location. For the same 72 hour period, it looks like the highest odds were for it to strike in NC, although even those were only 5%.

http://www.nhc.noaa.gov/archive/storm_wallets/atlantic/atl1992/andrew/strike/lal0492.018

Also, note in the advisory that was posted the 72 hour intensity was 65 knots or a minimal hurricane.

[Voltron]

Well from the models, it appears NC is pretty much clear for the most part aside from the normal rain and such. I just dont see a turn to NC or SC anytime soon

[Steve]

This is bad. NAM out to 66 hours. Absent a miracle we could probably all use, the question is one or two landfalls? Seriously. There goes the trough which we knew was going to happen, but it's 6 hours later now. Odds are the US is probably going to get hit by a 4 or 5.

https://www.tropicaltidbits.com/analysi ... 0&ypos=527