ATL: IDA - Remnants - Discussion

[Hammy]

Idk, the way I see it it still looks quite healthy for an intensifying cyclone, and if it fails to achieve at least Cat 4 status then I would be very curious to know what factor caused this given the forecasts saw light shear, high RH, a path over the Loop Current, and all of these factors strongly suggest a powerful cyclone.

The models don't seem to handle mid-level shear or dry air very well (look at Henri's model output for instance), so if it turns out it does come in under-forecast, those would be the most likely reason.

[aperson]

The dry slot on the SW is mixing out now and vortical hot towers are going up around the eyewall with lightning flashes. I think those that have been displeased with the storm's aesthetics so far won't need to wait more than a couple of hours from now.

[Highteeld]

Idk, the way I see it it still looks quite healthy for an intensifying cyclone, and if it fails to achieve at least Cat 4 status then I would be very curious to know what factor caused this given the forecasts saw light shear, high RH, a path over the Loop Current, and all of these factors strongly suggest a powerful cyclone.

The models don't seem to handle mid-level shear or dry air very well (look at Henri's model output for instance), so if it turns out it does come in under-forecast, those would be the most likely reason.

The opposite happened with Michael. The storm went through 20 knots of shear, but Michael instead was like, "YEEEEET".

[InfernoFlameCat]

I am having difficulty getting a read on this storm. Usually I can see what the trend is but this system is giving me trouble. I have no idea how strong it is right now TBH and that frustrates me.

[tallywx]

Idk, the way I see it it still looks quite healthy for an intensifying cyclone, and if it fails to achieve at least Cat 4 status then I would be very curious to know what factor caused this given the forecasts saw light shear, high RH, a path over the Loop Current, and all of these factors strongly suggest a powerful cyclone.

Probably inner core issues / broad wind field. Reminds me of Georges 1998 which had seemingly perfect conditions all the way across but couldn’t get higher than 110mph due to broad flat wind field.

[tarheelprogrammer]

I’m starting to get doubtful that Ida will make it to Category 4 intensity. Its current structure seems primed for an EWRC or just other competing bands to slow down intensification, with the exception of short bursts.

That does NOT mean it isn’t a huge threat. The very large radius of hurricane-force FL winds (and TS-H surface winds) in the NE quadrant means places on the east side of landfall, like New Orleans, are at risk for lots of storm surge. 7-11 feet is really bad. Hopefully the post-Katrina leeve improvements do their job well.

It’s on track for at least Cat 4 status.

Yes it is. People saying its not looking good, consider that its moving in favorable waters and an intensification cycle is currently underway

There are 30 hours between the eyewall and land, plenty of time to blow up

I thought it had about 15 hours or so according to the NHC. Someone please correct me.

[HurryKane]

Idk, the way I see it it still looks quite healthy for an intensifying cyclone, and if it fails to achieve at least Cat 4 status then I would be very curious to know what factor caused this given the forecasts saw light shear, high RH, a path over the Loop Current, and all of these factors strongly suggest a powerful cyclone.

Most likely it will be my voodoo chants combined with my overconsumption of hurricane snacks. A fearsome thing indeed.

(I will also be curious)

[tolakram]

Pinks starting to show up.

[Category5Kaiju]

Idk, the way I see it it still looks quite healthy for an intensifying cyclone, and if it fails to achieve at least Cat 4 status then I would be very curious to know what factor caused this given the forecasts saw light shear, high RH, a path over the Loop Current, and all of these factors strongly suggest a powerful cyclone.

The models don't seem to handle mid-level shear or dry air very well (look at Henri's model output for instance), so if it turns out it does come in under-forecast, those would be the most likely reason.

http://tropic.ssec.wisc.edu/real-time/sal/g16split/movies/goes16split.html

But that's precisely the thing though; dry air or mid-level shear do not seem to be issues at play here and for Ida's forseeable future, so if it underperforms then that would be very interesting as there must be some weird factor at play here that cannot be explained just by the aforementioned, primary factors.

[tolakram]

saved image with scale

[SEASON_CANCELED]

It’s on track for at least Cat 4 status.

Yes it is. People saying its not looking good, consider that its moving in favorable waters and an intensification cycle is currently underway

There are 30 hours between the eyewall and land, plenty of time to blow up

I thought it had about 15 hours or so according to the NHC. Someone please correct me.

I dont really count the swamps..until it reaches I-90 its still over water in my book

[grapealcoholic]

Wind field starting to symmetrize

[cheezyWXguy]

Wind field starting to symmetrize

http://tropic.ssec.wisc.edu/real-time/adt/09L-2DWIND.GIF

That’s impressive, and as far as I have been able to tell, this is the last box to check. If there isn’t a bump in intensity tonight, I will be at a loss for what the cause is.

[Highteeld]

Decent pressure drop, but nothing explosive

[Torgo]

I dont really count the swamps..until it reaches I-90 its still over water in my book

.

Southern Minnesota, then.

[SEASON_CANCELED]

I dont really count the swamps..until it reaches I-90 its still over water in my book

.

Southern Minnesota?

Nah like i said, it can still draw energy up until about I-90

[ElectricStorm]

966mb extrap. Another solid drop

[RL3AO]

I dont really count the swamps..until it reaches I-90 its still over water in my book

.

Southern Minnesota?

Nah like i said, it can still draw energy up until about I-90

You mean I-10?

[tallywx]

Each storm is different of course, but here was the old discussion from Hurricane Georges 1998 as it traversed the Gulf and also struggled against seemingly favorable conditions:

“ HURRICANE GEORGES DISCUSSION NUMBER 48
NATIONAL WEATHER SERVICE MIAMI FL
5 AM EDT SUN SEP 27 1998

THE INTENSITY OF GEORGES HAS NOT CHANGED SIGNIFICANTLY DURING THE PAST 24 HOURS. THE HURRICANE IS MOVING OVER A WARM OCEAN AND THE
SHEAR IS LOW BUT...AT THIS STAGE...THIS DOES NOT APPEAR TO BE ENOUGH FOR THE HURRICANE TO INTENSIFY RAPIDLY. IT HAS BEEN DISCUSSED IN MOST OF THE HURRICANE INTENSITY CHANGE WORKSHOPS...THAT...FOR RAPID INTENSIFICATION...THERE SHOULD BE AN EYEWALL REPLACEMENT CYCLE AND/OR A TROUGH INTERACTION. THESE TWO PROCESSES ARE VERY DIFFICULT TO EVALUATE...BUT WITH THE LIMITED AVAILABLE INFORMATION...NONE OF THE ABOVE PROCESSES ARE LIKELY TO OCCUR BECAUSE THE INGREDIENTS ARE
NOT PRESENT. THERE IS NOT A PERSISTENT AND WELL DEFINED INNER CORE...NO DOUBLE EYE STRUCTURE EITHER AND THERE IS NO UPPER-TROUGH APPROACHING THE HURRICANE. ONLY A SMALL INCREASE IN INTENSITY IS
THEN FORECAST BEFORE LANDFALL. THIS IS AN ARRESTED FORECAST BECAUSE THE ABOVE PROCESSES ARE STILL IN THEORY AND HAVE NOT BEEN TRANSLATED INTO OPERATIONAL TOOLS YET.”

[InfernoFlameCat]

Ida would have done better IMO with a slightly sheared environment due to its structure. It had to adjust to no shear so its method of strengthening did not work. again IMO