ATL: IDA - Models

[BobHarlem]

Outages this morning affecting HMON. That said HWRF is MUCH stronger so far, 24mb less at 54 hours than the 0z.

06z HMON having issues, or is it just TT having a delay, usually runs about 24 hours faster then the HWRF

 https://twitter.com/JackSillin/status/1431208494061981698

[kevin]

Cat 4 HWRF hurricane incoming:

[aspen]

940-944mb landfall around 03z-06z Monday on the HWRF.

[Kohlecane]

Outages this morning affecting HMON. That said HWRF is MUCH stronger so far, 24mb less at 54 hours than the 0z.

06z HMON having issues, or is it just TT having a delay, usually runs about 24 hours faster then the HWRF

https://twitter.com/JackSillin/status/1431208494061981698

Let the conspiracy theories begin!!!
Thank for that info though!

[xironman]

06z HMON having issues, or is it just TT having a delay, usually runs about 24 hours faster then the HWRF

That's one heck of a model.

[Kohlecane]

06z HMON having issues, or is it just TT having a delay, usually runs about 24 hours faster then the HWRF

That's one heck of a model.

From Intl. forecast

[Steve]

951 peak? Still got some time over water though...
Also, that's a big ass eye depicted on the HWRF. WTH?

Beast.

https://i.imgur.com/wH34Hp1.png

https://i.imgur.com/rRIFYh8.png

I have to be up at 5 for work but woke up to check all the model runs. What you say Steve, hope everything has been well? Louisiana almost always gets spared with these systems weakening on approach due to shear and especially dry air, but I just don’t see it this time around. This could definitely be Laura part 2. Except this time it’s our turn. Some of these tracks have the eye coming right over us. I remember how bad Gustav was even though it significantly weakened, this will be on a whole other level of which people have never seen around here before if the models are correct. Busting out the Chainsaws and generators tomorrow. Gas stations and grocery stores are going to be absolutely nuts around here.

Hey Mike. Everything has been good. This looks like a bad one that might set some future benchmarks for a lot of fellow Louisianians. Luckily all my **** is in Florida, so I don’t have that much to lose personally. But I hope you and your family make out as best as possible. If the 06 HWRF is right, look out! I’ll be out of town monitoring, so please do post some updates from the BR Metro if you can and as warranted.

[Kohlecane]

The first recon pass found a minimum pressure of 996.4 mbar.

note worthy that Hwrfs location is pretty accurate to this, but GFS 6z hit the Mb's more accurately still have more passes but seems we are getting better initialization overall, now lets just wait and see how the Euro does we all know how that went with Henri

[skyline385]

The first recon pass found a minimum pressure of 996.4 mbar.

note worthy that Hwrfs location is pretty accurate to this, but GFS 6z hit the Mb's more accurately still have more passes but seems we are getting better initialization overall, now lets just wait and see how the Euro does we all know how that went with Henri

GFS hit the initialisation pressure accurately but being a global model it's pressure plots at landfall for a system undergoing RI will be way off, NHC noted the same in their discussion yesterday as well. Meanwhile, HWRF has it dropping to 940mb while being initialised at 8mb higher than recon...

[Kohlecane]

The first recon pass found a minimum pressure of 996.4 mbar.

note worthy that Hwrfs location is pretty accurate to this, but GFS 6z hit the Mb's more accurately still have more passes but seems we are getting better initialization overall, now lets just wait and see how the Euro does we all know how that went with Henri

GFS hit the initialisation pressure accurately but being a global model it's pressure plots at landfall for a system undergoing RI will be way off, NHC noted the same in their discussion yesterday as well. Meanwhile, HWRF has it dropping to 940mb while being initialised at 8mb higher than recon...

Never thought about that. Well there is one common scheme to IDA and that's it wants to out perform everyone, whether its intensity or movement

[Category5Kaiju]

The first recon pass found a minimum pressure of 996.4 mbar.

note worthy that Hwrfs location is pretty accurate to this, but GFS 6z hit the Mb's more accurately still have more passes but seems we are getting better initialization overall, now lets just wait and see how the Euro does we all know how that went with Henri

GFS hit the initialisation pressure accurately but being a global model it's pressure plots at landfall for a system undergoing RI will be way off, NHC noted the same in their discussion yesterday as well. Meanwhile, HWRF has it dropping to 940mb while being initialised at 8mb higher than recon...

Using a very simplistic approach, that would roughly mean a 932 mbar landfall. That's solid Cat 4 there.

[underthwx]

Cat 4 HWRF hurricane incoming:

https://i.imgur.com/0NZsyOI.png

https://i.imgur.com/3nJaVeo.png

Let's hope that won't pan out...

[Cataegis96]

Appears the LLC just got tugged north more closely aligned with the MLC. IR presentation quickly improving. Cuba likely needs hurricane warnings.
https://bmcnoldy.rsmas.miami.edu/tropics/ida21/Ida_26Aug21_Cayman.gif

edit Meant to post this in the Discussion thread. In relation to the models, looks like this will be following the 6z HWRF's predicted poleward jump and skirt north over the Isle of Youth.

[aspen]

The HWRF’s predicted position for 15z (right about now) is pretty much spot-on with the location, central pressure, and winds.

[MississippiWx]

Appears the LLC just got tugged north more closely aligned with the MLC. IR presentation quickly improving. Cuba likely needs hurricane warnings.
https://bmcnoldy.rsmas.miami.edu/tropics/ida21/Ida_26Aug21_Cayman.gif

Wow. Pretty cool to watch that happen on radar. Good catch.

[Shell Mound]

Outages this morning affecting HMON. That said HWRF is MUCH stronger so far, 24mb less at 54 hours than the 0z.

06z HMON having issues, or is it just TT having a delay, usually runs about 24 hours faster then the HWRF

https://twitter.com/JackSillin/status/1431208494061981698

Let the conspiracy theories begin!!!
Thank for that info though!

If I recall correctly, similar problems with reconnaissance instrumentation occurred during Katrina.

[PTrackerLA]

06z Euro ensembles

[jaguars_22]

I recently heard that a trough would likely keep the high from rebuilding west. Is that trough still showing in the models?

[p1nheadlarry]

Would the immense diabatic heating that leads to PV annihilation aloft cause the storm to go further west and extend the ridge south and west a bit?

[Shell Mound]

Would the immense diabatic heating that leads to PV annihilation aloft cause the storm to go further west and extend the ridge south and west a bit?

I believe so. If that is the case, then the current eastward bias would eventually “flatten” as the storm assumes a sharper W component over the Gulf. A stronger ridge might also lead to a somewhat smaller storm, owing to elevated background pressures. The 06Z HWRF actually depicts a somewhat more compact wind field than earlier runs, while also trending toward a much deeper/stronger Ida. While this may reduce the risk of surge to areas outside the inner core, I do think that Ida could end up being much more of a wind-based threat than any of 2020’s hurricanes were in Louisiana. Given current trends, upcoming conditions, and the tendency of models to underestimate RI under conducive conditions, I think Ida could certainly become roughly as strong as Michael prior to and during landfall in Louisiana. Expect future runs to trend toward an even stronger TC at LF.