ATL: IDA - Models

[Kohlecane]

12z UKMET
https://i.imgur.com/2efwEPZ.png

Euro and UKMET are usually west-biased in the Gulf. The GFS is right biased. Good to split the difference between the Euro and GFS usually.

Couldn't have said it any better , was gonna say it does tend to be west bias especially when you look back at Grace, every other model wanted it through the GA and UK was a B-line to the Yucatan Peninsula and it was pretty accurate with it's forecast

[p1nheadlarry]

12z UKMET
https://i.imgur.com/2efwEPZ.png

Is it just me is UKMET sort of always the most west biased of the models for gulf storms? I never see it much since its not as accessible but I feel like years past its always west bias, but sometimes nails it?

UKMET definitely has a west bias, I'd say more so than the Euro anecdotally.

[p1nheadlarry]

As mentioned in the past here is sim IR 48-66hr, and the question we have asked is shear on the W side, but looking at this, it looks like it's more from landfall, unless that shear comes quick and fast https://s9.gifyu.com/images/hwrf-48-66.jpg

Its W half narrows as Ida approaches LF, so HWRF does show some shear, but perhaps too late. Also, most models show RI levelling off just before LF in southern LA, suggesting the influence of increasing westerly shear resulting in constricted outflow on the W side of the storm. See below:

https://twitter.com/EricWMUR/status/1431313531413086215

And with ~72 hours until landfall that better be the best damned timed EWRC ever (honestly even then can't weaken all that much)

[crownweather]

I just tweeted this out.

 https://twitter.com/crownweather/status/1431330717871509507

[Shell Mound]

 https://twitter.com/StormCoker/status/1431332849093853190

[SconnieCane]

12z UKMET
https://i.imgur.com/2efwEPZ.png

Euro and UKMET are usually west-biased in the Gulf. The GFS is right biased. Good to split the difference between the Euro and GFS usually.

Euro and even its ensemble (EPS) kept Galveston/Houston on their toes with Laura, before joining the near-total consensus on a Calcasieu Pass bullseye at the last minute. I seem to recall at one point the UKMET wanted to get even Sally there.

[tolakram]

Here's the Euro's landfall graphic.

[petit_bois]

Does the commonly mentioned theory come into play here with IDA?
"Stronger systems tend to move more poleward, weaker systems tend to move more lateral"

[LSU2001]

I am not up to speed on this board since I haven’t been visiting as much as I used to visit. But I have to ask where is Aric Dunn? I haven’t seen one post from him on this storm and normally he and wxweather or whatever his handle is, arguing over storm structure and what will happen next. I was wondering if he managed to get banned or something.
Thanks,
Tim

[tolakram]

I am not up to speed on this board since I haven’t been visiting as much as I used to visit. But I have to ask where is Aric Dunn? I haven’t seen one post from him on this storm and normally he and wxweather or whatever his handle is, arguing over storm structure and what will happen next. I was wondering if he managed to get banned or something.
Thanks,
Tim

He posted some for Elsa, not sure since then.

 https://twitter.com/ECMWFbot/status/1431346563691868163

[Shawee]

https://twitter.com/StormCoker/status/1431332849093853190

That is from yesterday. But thanks for the moment of hope.

[p1nheadlarry]

Does the commonly mentioned theory come into play here with IDA?
"Stronger systems tend to move more poleward, weaker systems tend to move more lateral"

It ultimately depends on synoptic pattern and other dynamics, but the general idea is the displacement is dependent on a "-Beta*V" term, so the stronger the winds the larger the poleward component (also since beta is the gradient of planetary vorticity, larger storms also cause this term to grow)

[IcyTundra]

Yikes the 18Z ICON intialized 14 MB too weak and still gets it down to 955 MB at landfall.

[CrazyC83]

Yikes the 18Z ICON intialized 14 MB too weak and still gets it down to 955 MB at landfall.

Track is virtually unchanged though.

[Hypercane_Kyle]

18z GFS initialization also too weak.

[tolakram]

18Z GFS

[IcyTundra]

At this point with the track pretty much locked in the global models aren't going to be very useful as they often have a hard time with intensity forecasts. The hurricane models HWRF and HMON handled Grace's intensity pretty well in the 48 hours leading up to landfall will be interesting to see how close they are to the actual intensity for Ida.

[tolakram]

18Z HWRF init

[cheezyWXguy]

Might be worth noting that a few of the gefs members came in a little east this round. The spread looks a little wider

[tolakram]

HWRF, for documentation purposes (which is why I post models, even near landfall)