ATL: ISAIAS - Models

[cycloneye]

 https://twitter.com/RaleighWx/status/1290265054932340736

[cycloneye]

Question for the model huggers. Which model or models performed the best with Isaias from the start as a Tropical Wave east of the Lesser Antilles?

[fox13weather]

With so many models showing Isaias moving inland within 36 hours, why is the NHC consistently hugging the right side of guidance?

So many? The ECMWF has actually trended to the east the past few runs ...consensus is up the coast and I have lost track of the number of storm that were supposed to make landfall on the east coast of Florida only to stay 50 miles offshore...

No the ECM actually shifted inland quite a bit in its 12z run from its offshore 00z previous run. So much so that Rick Knabb (former director of NHC) now on TWC consistently showed that run to warn tonight the center might likely come inland in Florida. The 18z Euro shifted slightly east from the 12z run, but it still tracks inland. Meanwhile, the major models on the right side of the guidance at 12z such as the GFS, GFS para, and HWRF have all shifted West on their 18z runs. Add in the UKMET, CMC, ICON, and NAVGEM as other models that now track inland in Florida and I think that's shaping up to be a pretty strong consensus. Could Iasias still stay offshore? Sure but Weight of evidence suggests less likely at this point.

..as i was saying ....I have lost track of the number of storm that were supposed to make landfall on the east coast of Florida only to stay 50 miles offshore...

[Steve]

Question for the model huggers. Which model or models performed the best with Isaias from the start as a Tropical Wave east of the Lesser Antilles?

It's hard to say. Some of them were almost dead on many many days out. But most of them had issues along the way. I thought the Canadian was too far west for several runs late when it should have known better (near interaction with Florida). UKMET did in some of its runs as well. Also the EC. NAM kept it offshore of Florida and HRRR mostly did though it timed a lot of the pulses pretty well (expected when a short term model runs every hour).

Here's an interesting run for you though. I went back 6 days (ICON 18z last Wednesday).
https://www.tropicaltidbits.com/analysi ... 2918&fh=48

Compare that to the GFS which wasn't bad but was too far East
https://www.tropicaltidbits.com/analysi ... 918&fh=144

Here's the Canadian from 6 hours later (Thursday 00Z). Like the GFS it was in the ballpark but too far west instead of being too far East like the GFS
https://www.tropicaltidbits.com/analysi ... 000&fh=222

EC was similar to the CMC (this is last Thursday 00z)
https://www.tropicaltidbits.com/analysi ... 000&fh=108

Just something to reference next time ICON gets arbitrarily trashed. I'm still feeling it out, but it's had some success this year.

Next Point of Comparison will be 00Z Saturday. For those of you who endlessly remind us that but it's the NAM or routinely bash it saying it's not to be used for the tropics, the rest of us understand that. We also understand this. It worked very well for those upcoming 60 hours. That's not a lot of time (2 1/2 days), but it shows some value there.

NAM 3k 00Z Saturday
https://www.tropicaltidbits.com/analysi ... 0100&fh=84

[toad strangler]

..as i was saying ....I have lost track of the number of storm that were supposed to make landfall on the east coast of Florida only to stay 50 miles offshore...

It's been nearly 15 years now since a Hurricane FL East Coast landfall.

[SconnieCane]

It's been nearly 15 years now since a Hurricane FL East Coast landfall.

...and the one that didn't stay offshore and go north missed south/west (Irma). Force field in effect.

[cycloneye]

Question for the model huggers. Which model or models performed the best with Isaias from the start as a Tropical Wave east of the Lesser Antilles?

It's hard to say. Some of them were almost dead on many many days out. But most of them had issues along the way. I thought the Canadian was too far west for several runs late when it should have known better (near interaction with Florida). UKMET did in some of its runs as well. Also the EC. NAM kept it offshore of Florida and HRRR mostly did though it timed a lot of the pulses pretty well (expected when a short term model runs every hour).

Here's an interesting run for you though. I went back 6 days (ICON 18z last Wednesday).
https://www.tropicaltidbits.com/analysi ... 2918&fh=48

Compare that to the GFS which wasn't bad but was too far East
https://www.tropicaltidbits.com/analysi ... 918&fh=144

Here's the Canadian from 6 hours later (Thursday 00Z). Like the GFS it was in the ballpark but too far west instead of being too far East like the GFS
https://www.tropicaltidbits.com/analysi ... 000&fh=222

EC was similar to the CMC (this is last Thursday 00z)
https://www.tropicaltidbits.com/analysi ... 000&fh=108

Just something to reference next time ICON gets arbitrarily trashed. I'm still feeling it out, but it's had some success this year.

Next Point of Comparison will be 00Z Saturday. For those of you who endlessly remind us that but it's the NAM or routinely bash it saying it's not to be used for the tropics, the rest of us understand that. We also understand this. It worked very well for those upcoming 60 hours. That's not a lot of time (2 1/2 days), but it shows some value there.

NAM 3k 00Z Saturday
https://www.tropicaltidbits.com/analysi ... 0100&fh=84

Thank you for that.

[Steve]

No problem. That's just the stuff I saw. I always forget the link where they evaluate the models, but I'm sure someone will have it.

[Blown Away]

No problem. That's just the stuff I saw. I always forget the link where they evaluate the models, but I'm sure someone will have it.

Steve, you did a good job posting models and providing your opinions on how Isaias would impact the NE.

[Steve]

No problem. That's just the stuff I saw. I always forget the link where they evaluate the models, but I'm sure someone will have it.

Steve, you did a good job posting models and providing your opinions on how Isaias would impact the NE.

Thanks Blown. I just typed what I thought I saw. I started paying much closer attention late last week when most of the talk was on Florida. But it seemed likely there would be a Part 2/3 because the way out for the system was to the north through SC/NC and essentially up the entire east coast but fairly close to the coast. Where we got lucky, and it was a curiosity to me early last weekend, was why wasn't a storm coming up through that part of the ocean likely to strengthen into a monster storm. Most of the models I looked at showed maybe 977 or 978 as the absolute lowest. So the models were telegraphing that we might have caught a break. I assume the combination of the date, super dry air early on to the west, Phase 4 MJO and the SW shear was what held it back. But on the other hand, there was a decent chance a strong tropical storm or possibly lower end hurricane was going to hit and no doubt affect 10's of millions of people and plenty of us here. So I thought it was worth putting out whatever effort I could for anyone who had time to see what I was looking at.

[toad strangler]

No problem. That's just the stuff I saw. I always forget the link where they evaluate the models, but I'm sure someone will have it.

Steve, you did a good job posting models and providing your opinions on how Isaias would impact the NE.

Thanks Blown. I just typed what I thought I saw. I started paying much closer attention late last week when most of the talk was on Florida. But it seemed likely there would be a Part 2/3 because the way out for the system was to the north through SC/NC and essentially up the entire east coast but fairly close to the coast. Where we got lucky, and it was a curiosity to me early last weekend, was why wasn't a storm coming up through that part of the ocean likely to strengthen into a monster storm. Most of the models I looked at showed maybe 977 or 978 as the absolute lowest. So the models were telegraphing that we might have caught a break. I assume the combination of the date, super dry air early on to the west, Phase 4 MJO and the SW shear was what held it back. But on the other hand, there was a decent chance a strong tropical storm or possibly lower end hurricane was going to hit and no doubt affect 10's of millions of people and plenty of us here. So I thought it was worth putting out whatever effort I could for anyone who had time to see what I was looking at.

Vigorous westerly shear was the main culprit and it weaponized the dry air by reaming it right into Isaias kitchen. So shear is numero uno and why peninsular FL saw next to nothing.