ATL: DORIAN - Models

[jlauderdal]

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06z Legacy now landfalls near Melbourne and slides NW in Orlando as a 977 mb hurricane.

977 is far better than what we saw with the hwrf

[ronjon]

Heres a Frances flashback for those that remember.

https://www.google.com/search?q=hurricane+frances+path&oq=hurricane+Fra&aqs=chrome.1.0l4j69i57j0l11.9828j0j4&sourceid=silk&ie=UTF-8#imgrc=Iipaov-wOui80M:

[SouthFLTropics]

06z HMON coming in stronger...down to 945mb at 30 hours. Slightly South of 00z.

[dizzyfish]

I have a question...….

Last evening and this morning Channel 13 (FOX) in Tampa showed a model that included the predicted wind speeds as Dorian moved through the state for that particular model. (I think it was the Euro) Is that something that is available to the general public or is that a proprietary item?

[NDG]

Right now a blend between the Euro, UKMET, ICON and GFS looks to be the best option, as always. Which means southern central FL has the highest chance of landfall.
Euro and UKMET with their usual over doing of ridging around days 4-7 while the GFS under doing it.

[Ken711]

icon, euro and gfs all slow it around the same period, that much they agree on....miami to jax still in play but a clear south trend with this new gfs, nhc will come a little farther south, not much...everyone close to 95 in florida needs to prepare for a major

By slowing will that reduce the intensity hopefully?

[p1nheadlarry]

I have a question...….

Last evening and this morning Channel 13 (FOX) in Tampa showed a model that included the predicted wind speeds as Dorian moved through the state for that particular model. (I think it was the Euro) Is that something that is available to the general public or is that a proprietary item?

https://weather.us/model-charts/euro/fl ... -330f.html

[Aric Dunn]

Today synoptic flight will be key. Now that erin is outnof the picture. will be the first reall sampling of the new building ridge.

Its oreintation is key to how far west and if there will be a wsw bend at some point.

[Nimbus]

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06z Legacy now landfalls near Melbourne and slides NW in Orlando as a 977 mb hurricane.

977 is far better than what we saw with the hwrf

06Z HWRF is a tad further north early in the run.
Will be interesting to see if that equates to a landfall closer to 28?
I'm concerned about the stall followed by a loss of latitude scenario.

[USTropics]

I have a question...….

Last evening and this morning Channel 13 (FOX) in Tampa showed a model that included the predicted wind speeds as Dorian moved through the state for that particular model. (I think it was the Euro) Is that something that is available to the general public or is that a proprietary item?

You can get it at weather.us for free. Zoom in on Fl, under "All Parameters" click on "Wind, gusts, direction" and choose "Wind direction and mean wind speed". Link (https://weather.us/model-charts/euro/fl ... 1800z.html) is for the ECMWF starting on Monday at 1:00PM. You can do this for several different models and even zoom into counties.

[Aric Dunn]

Right now a blend between the Euro, UKMET, ICON and GFS looks to be the best option, as always. Which means southern central FL has the highest chance of landfall.
Euro and UKMET with their usual over doing of ridging around days 4-7 while the GFS under doing it.

So i did confirm at least from a person associated ish. . Nhc does still use the super ensemble and lean towards it.

So its likely why they have been just slightly different then the model consensus we see.

They are seeing things we are not ..

[USTropics]

Right now a blend between the Euro, UKMET, ICON and GFS looks to be the best option, as always. Which means southern central FL has the highest chance of landfall.
Euro and UKMET with their usual over doing of ridging around days 4-7 while the GFS under doing it.

So i did at least from a person associated ish. . Nhc does still use the super ensemble and lean towards it.

So its likely why they have been just slightly different then the model consensus we see.

They are seeing things we are not ..

They give extra weight towards the HCCA (HFIP Corrected Consensus Approach) in addition to the FSU Super Ensembles. Both use the model output tracks from operational runs but apply known biases in the models for a corrected consensus.

[Aric Dunn]

Right now a blend between the Euro, UKMET, ICON and GFS looks to be the best option, as always. Which means southern central FL has the highest chance of landfall.
Euro and UKMET with their usual over doing of ridging around days 4-7 while the GFS under doing it.

So i did at least from a person associated ish. . Nhc does still use the super ensemble and lean towards it.

So its likely why they have been just slightly different then the model consensus we see.

They are seeing things we are not ..

They give extra weight towards the HCCA (HFIP Corrected Consensus Approach) in addition to the FSU Super Ensembles. Both use the model output tracks from operational runs but apply known biases in the models for a corrected consensus.

Yeah, i would wager this is why for the life of Dorian especially the first advisories they were off from the model consensus we see. They were showing a hurricane in the northern carrib. When everything we saw did not.

[Nimbus]

It's a matter of timing between the ECMWF and GFS model on how quickly the ridge begins to retrograde back east and to what extent it extends westward. You can see this even 72 hours from now. The GFS moves it out earlier, which allows Dorian to round the periphery of the ridge a bit quicker than the ECMWF:
https://i.ibb.co/WGg5sBk/Webp-net-gifmaker-6.gif

Both models show a collapse in steering currents and a break in the ridge for this to turn north. There's a reason such a huge spread in the ECMWF ensembles exist from 12z to 00z, how quickly the ridge retreats and how far west Dorian gets will determine when Dorian moves north. You can see this in the ECMWF ensembles, here is an image of them just out to 120 hours:

https://i.ibb.co/hfrsFpn/ECMWF-120.jpg

Now add another 48 hours to those ensemble members, and the ones that have reached the GOM at 120 hours turn north towards panhandle, the ones off the Florida coast turn north to a recurve, and the one's over Florida move north up the spine:

https://i.ibb.co/cXnw0Wz/ECMWF-168.jpg

The UKMET ensembles show a very similar evolution:
https://i.imgur.com/VqAj4Ee.jpg

The tracks depicting the stronger storms are following the deeper steering.
Deeper steering has shifted north before the coast which is a major change this run.

edit to add: 06z HWRF is depicting a stronger storm for 06z with a landfall further north so the NHC track does not have to be moved south.

[toad strangler]

They're slowing it down because now a recurve very near the coast is in the cards. The GFS is part of the multi-model consensus.

I think what you meant was the re-curve near the coast is in the cards because it's slowing down. Not the other way around.

The ECMWF has consistently modeled the northern turn to occur around Wednesday. That didn't change with this latest run.

What did change is the movement of Dorian westward was modeled much slower, thus the northern turn occurring over the Florida peninsula instead of the GOM.

I was saying this last night when the 11PM cone came out and was shrugged off. It was the biggest development in my eyes in the 18z and later runs

[Aric Dunn]

Given the setup i just dont see it getting that far north before turning westerly. I have a feeling we are going to see an even more gradual left turn before turning dew west. Which would bring it a little more south.

[gatorcane]

06Z NAVGEM into South Florida again. Looks similar to the Euro:

[CronkPSU]

icon, euro and gfs all slow it around the same period, that much they agree on....miami to jax still in play but a clear south trend with this new gfs, nhc will come a little farther south, not much...everyone close to 95 in florida needs to prepare for a major

By slowing will that reduce the intensity hopefully?

maybe but they are not forecasting much shear during that time and it will be moving (not stalled) over those warm SST's and Gulf Stream

[Bocadude85]

6z HMON is heading due west south of Grand Bahama

[northjaxpro]

It's a matter of timing between the ECMWF and GFS model on how quickly the ridge begins to retrograde back east and to what extent it extends westward. You can see this even 72 hours from now. The GFS moves it out earlier, which allows Dorian to round the periphery of the ridge a bit quicker than the ECMWF:
https://i.ibb.co/WGg5sBk/Webp-net-gifmaker-6.gif

Both models show a collapse in steering currents and a break in the ridge for this to turn north. There's a reason such a huge spread in the ECMWF ensembles exist from 12z to 00z, how quickly the ridge retreats and how far west Dorian gets will determine when Dorian moves north. You can see this in the ECMWF ensembles, here is an image of them just out to 120 hours:

https://i.ibb.co/hfrsFpn/ECMWF-120.jpg

Now add another 48 hours to those ensemble members, and the ones that have reached the GOM at 120 hours turn north towards panhandle, the ones off the Florida coast turn north to a recurve, and the one's over Florida move north up the spine:

https://i.ibb.co/cXnw0Wz/ECMWF-168.jpg

The UKMET ensembles show a very similar evolution:
https://i.imgur.com/VqAj4Ee.jpg

Great illustrations and analysis USTropics on the complex steering challenges in the forecast track of Dorian. This is going to drive me insane trying to see how it shakes down this weekend.