ATL: IDALIA - Post-Tropical - Discussion

[Jr0d]

Recency bias is a real thing because Tampa Bay was evacuated during Ian and turned out to be nothing for Tampa Bay. Now they will wait till as long as they can before issuing anything. The stronger this storm gets the higher the chances of it turning east earlier than forecasted in my opinion. History shows that clearly.

I am trying to think of storms in this area that went 'left' of the official forecast, especially ones that are forecast to eventually turn northeast.

Obviously Ian and Charlie turned east further south than expected and were stronger than originally forecasted approx 36 to 48 hours before landfall.

We will see what the models show in a few hours, I believe it will be the first run with updated data.

Despite the blow up last night, there appears to be at least a temporary pause on strengthening, with a heavily lopsided system. Unfortunately there is little to prevent strengthening now until landfall somewhere on the Florida Gulf coast.

[GCANE]

Strong MCS moving south into the GoM.
Over the MS Delta ahead of the trof.
Firing along a strong CAPE gradient.
Moistening the troposphere ahead of Idalia

[LandoWill]

I would expect tampa to wait till 11am advisory, it's still not north of cuba. 11AM at the earliest, waiting till 5pm would be rough, since nothing is changing. But, i think that's the plan. i don't have local tv . so i dunno what they saying here in tampa I'm north of tampa anyway

[tolakram]

5AM track forecast



Peak surge estimates

[cheezyWXguy]

Looking at radar, Idalia appears to be trying to wrap thunderstorms around the east side of the core again, but not convinced yet that this attempt will be successful. One thing in its favor is that, for the first time that I can recall, there’s a feeder band establishing itself in the western semicircle

[Hypercane_Kyle]

Recency bias is a real thing because Tampa Bay was evacuated during Ian and turned out to be nothing for Tampa Bay. Now they will wait till as long as they can before issuing anything. The stronger this storm gets the higher the chances of it turning east earlier than forecasted in my opinion. History shows that clearly.

I am trying to think of storms in this area that went 'left' of the official forecast, especially ones that are forecast to eventually turn northeast.

Obviously Ian and Charlie turned east further south than expected and were stronger than originally forecasted approx 36 to 48 hours before landfall.

We will see what the models show in a few hours, I believe it will be the first run with updated data.

Despite the blow up last night, there appears to be at least a temporary pause on strengthening, with a heavily lopsided system. Unfortunately there is little to prevent strengthening now until landfall somewhere on the Florida Gulf coast.

Seems the trend for rapidly intensifying storms approaching the FL gulf coast is to divert suddenly southeast.

[kevin]

Recon found 68 kt FL winds in the NE quadrant.

[Fancy1002]

Looks like one plane is finding lower pressure and lower winds, while the other plane is finding higher pressure but higher winds.

[Hypercane_Kyle]

Recon found 68 kt FL winds in the NE quadrant.

Supports 55-60 knots right now.

Looks like one plane is finding lower pressure and lower wins, while the other plane is finding higher pressure but higher winds.

They're flying at different altitudes. NOAA plane is higher.

[sponger]

Euro appears too weak and new hurricane models look too far North for the strength they are predicting. Could the UK Met be on to something? Slightly worse for Tampa and Jacksonville gets a high end cat one hit. I really worry for Tampa South if this gets to high end Cat 3.

06z UKMET - decent shift E, and to the right of the Official Track.

https://i.imgur.com/DJU8RXP.png

[Teban54]

Recon found 68 kt FL winds in the NE quadrant.

And it wasn't even a center pass...

[kevin]

68 FL is enough to support 61 kt at the surface -> 65 kt based on undersampling. SFMR isn't at the same level yet so they might keep it at 60 kt, but Idalia is on its way to become a hurricane (if it isn't one already).

[Jr0d]

I would expect tampa to wait till 11am advisory, it's still not north of cuba. 11AM at the earliest, waiting till 5pm would be rough, since nothing is changing. But, i think that's the plan. i don't have local tv . so i dunno what they saying here in tampa I'm north of tampa anyway

This is tough. I think we can admit the models have not been extremely accurate this year.

While the current model consensus shows Idalia far enough north of Tampa to potentially limit surge, it will not take much of a wobble to change this drastically.

Hopefully the storm will move relatively quickly and not surprise us with a slower than expected speed as it approaches, making surge worse.

While major hurricane winds are serious, the major concern here is massive flooding of Tampa Bay. After a close call with Ian, I just hope many at risk have not become complacent.

[Fancy1002]

Recon found 68 kt FL winds in the NE quadrant.

Supports 55-60 knots right now.

Looks like one plane is finding lower pressure and lower wins, while the other plane is finding higher pressure but higher winds.

They're flying at different altitudes. NOAA plane is higher.

Oh ok.

[chris_fit]

Whoa, the orange barbs are out in full force....

[LandoWill]

Waking up to everyone, professionals included, in Bradenton and St. Pete practically sounding the all clear alarm. Been a little disappointing to see the complete lack of concern around here

Just watched WTVT they gave caution about if it even moves a few miles east, it may be problematic, but otherwise we have 30 hours to prepare. But, right now all is ok if it stays west... he's not talking about the coast i don't think though

[cheezyWXguy]

68 FL is enough to support 61 kt at the surface -> 65 kt based on undersampling. SFMR isn't at the same level yet so they might keep it at 60 kt, but Idalia is on its way to become a hurricane (if it isn't one already).

One thing to watch for today is how the windfield evolves. Right now, Idalia is very lopsided, with virtually all ts winds on the east side. If it can symmetrize its windfield, it will be all systems go for faster intensification. However, if it doesn’t, that will hold a lid on it for longer. This was a big sticking point for Ian while south of Cuba until the last few hours before landfall when it blew up.

[eastcoastFL]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 28 AUG 2023 Time : 114020 UTC
Lat : 20:23:07 N Lon : 85:10:29 W


CI# /Pressure/ Vmax
3.1 / 992.2mb/ 47.0kt


Final T# Adj T# Raw T#
3.1 3.4 3.9

[tolakram]

Euro appears too weak and new hurricane models look too far North for the strength they are predicting. Could the UK Met be on to something? Slightly worse for Tampa and Jacksonville gets a high end cat one hit. I really worry for Tampa South if this gets to high end Cat 3.

06z UKMET - decent shift E, and to the right of the Official Track.

https://i.imgur.com/DJU8RXP.png

6Z UKMET comes in at Jena, all models have a pretty tight grouping with no consistent drift so far. Details in model thread.

[sponger]

Euro appears too weak and new hurricane models look too far North for the strength they are predicting. Could the UK Met be on to something? Slightly worse for Tampa and Jacksonville gets a high end cat one hit. I really worry for Tampa South if this gets to high end Cat 3.

06z UKMET - decent shift E, and to the right of the Official Track.

https://i.imgur.com/DJU8RXP.png

6Z UKMET comes in at Jena, all models have a pretty tight grouping with no consistent drift so far. Details in model thread.

True but the exit is 80 miles to the South, a huge difference in impact. Add in a few extra feet of storm surge for Tampa and you have a very dicey situation. I would not want to be in NHC's shoes but I think Tampa has to be ready for the worst. Also the landfall looks to be just South of Cedar key.