ATL: IDA - Remnants - Discussion

[tolakram]

saved loop

[floridasun78]

hope dont see kartina type of hurr the gulf water very hot with no shear or little

[hipshot]

I don't know, it was a new build but we bought it as a spec house so we did not over-see construction. Hopefully everything was up to code. I guess we are about to find out. I do feel safe in it, though.

Louisiana is not Florida, of course. (aside:s "You are not a horse. You are not a cow"). But, in S. Florida in 1992 after Hurricane Andrew blew through: it was the homes built before the 1970s that held up well. It was the newer homes that fell apart. Depends on things like ever-changing stronger and weaker building codes, the level of corruption in the inspector corps and the builders themselves. Basically, almost every home that was made of concrete blocks, who had their windows shuttered, and had a relatively new roof, fared well. Even those homes that lost roofs basically got waterlogged inside; but the walls in most cases stood sturdy. Many of the newer homes in certain areas (like Country Wallk) had 2nd stories, which were made of wood and wall board, and proved quite aerodynamic. Those Spanish tiles on the newer homes, also proved very aerodynamic. I found several of them embedded in the inside walls of the room whose shutter had taken leave in that 175 mph gust. Like you said, you might find out in a few days.

I lived in Lake Worth, south of West Palm for only 10 months back in 1977 and that home was CBS construction, concrete block and steel, so as to withstand
a strong hurricane. It wasn't tested when I lived in it, thank God, but it should have held up if the roof was new enough. I didn't build it, it was
a used home but I was told that was the code back then.

[ScottNAtlanta]

saved loop
https://imgur.com/7N7LlUF

Looks like an eye trying to pop out before going onshore
I guess we are at an eye warning

[tolakram]

saved loop

[tiger_deF]

Are we seeing the beginnings of a Matthew-esque side blob?

[Hurricaneman]

Making Cuban landfall now, should be offshore between 9 and 10

[StPeteMike]

We will have to see how much Ida expands to get an almost accurate amount of storm surge NOLA gets. A Katrina size storm would be catastrophic while if it keeps it current size, the city may miss the worse of storm surge. That also includes if it stays on the exact track the NHC has it on. A right shift would place it just as catastrophic, even at its current size.

I just hope the city upgraded the levees along the lake as much as they did along the river.

[bella_may]

I wouldn’t rule out 60-70mph gusts as Far East as mobile

[Gums]

Salute!

where is Steve? Live on Northshore, if I recall.
Katrina was a big cat3,but main thing was the immense surge to the east, and the the levee failures in New Orleans.
This storm looks more like Camille with big surge on coastal places south of NOLA, and more wind than Katrina.

I would be more worried about gasoline in three or four weeks now that Keystone addition canceled as about 25% of our petrol comes thru Fourchon where the storm is headed.

Gums sends...

[Owasso]

 https://twitter.com/burgwx/status/1431376972144336908

[MONTEGUT_LA]

It's like reading a high-risk outlook from the SPC. Strong wording for sure.

It's definitely one of those that really jumps at you. I'd be concerned about levees there.

Ida could become the worst hurricane to affect Terrebonne Parish since the 1856 Last Island hurricane (130 kt/934 mb). The 1856 hurricane is officially tied with 2020’s Laura (130 kt/939 mb) as Louisiana’s strongest on record, as measured by maximum sustained wind (MSW), though arguably 1957’s Audrey was at least as intense as these two storms, and was likely on the order of 130 kt/925 mb at LF. 1965’s Betsy is in third or fourth place, having made LF on LA with MSW of 115 kt (MSLP: 946 mb).

Ida will rival Hurricane Betsy (1965) in intensity at landfall in SE Louisiana. I'd be boarding up and getting out if I were where the RFQ is expected. I remember quite well, it left New Orleans in shambles for weeks. Heed evacuation warning.....MGC

Was Betsy the strongest hurricane in terms of wind speed to hit Lousianna in recorded history? I know Camille was stronger for the GOM but it made landfall in Mississippi.

1969’s Camille bypassed the mouth of the Mississippi River at 135 kt/919 mb. My personal rankings of the strongest hurricanes on record in Louisiana:

• 1969 Camille: 135 kt/919 mb◇
• 1856 “Last Island”: 130 kt/934 mb
• 1957 Audrey: 130 kt/925 mb*
• 2020 Laura: 130 kt/939 mb✽
• 1965 Betsy: 115 kt/946 mb

◇Did not make landfall in LA, but passed close by
*Unofficial, personal estimation
✽Disputed, could be closer to 100 kt/945 mb

We heading out west early tomorrow morning... this is definitely not going to be good and these local officials are banking on their levee system. I dont swim... levees break every small storm... I have family staying behind... Hopefully, they change their minds im time.

[kevin]

Ida over land is looking better than Elsa and Henri were over open water. The hilly terrain of Cuba will be the final chance for some disruption, after that I'm confident we'll see RI the likes of which we don't often see in the Atlantic.

[xironman]

Nice looking tower building up.

[zal0phus]

I shudder to think of what the ceiling for Ida is. Dare I say, I think it might be our first sub-900 storm in years if everything goes wrong.
It's silly but I've always wanted to visit New Orleans someday. I hope I still get the chance with this in mind.

[ThetaE]

Sorry to repeat myself, here, but maybe including a picture or two will help:

https://i.ibb.co/pbsJLjs/COD-GOES-East-regional-gulf-10-20210827-192617-over-map-bars.jpg

That's a low-level water-vapor shot from the COD site. There's obviously 's a lot of dry air around Ida, although it's at a low level. Medium-levels are significantly more humid, but still on the dry side:

https://i.ibb.co/fSqgqPL/COD-GOES-East-regional-gulf-09-20210827-194117-over-map-bars.jpg

My question is about the low-level air. Does low-level dry air affect the deepening of a tropical cyclone, or does it have to be closer to mid-levels to matter? Obviously, Ida is intensifying quickly, but would it be significantly faster if the low-level dry air weren't there?

Thanks!

Hey! College of DuPage has great satellite graphics, but honestly the distinction between low, mid, and high WV has never made much sense to me. For instance, the "low" WV loop shows plenty of cirrus/outflow-related features. Outside of areas of deep convection, the low-level channel always looks super dry like that.

If you want a more reliable sense of moisture in the low levels, check out some of the dropsondes from the NOAA9 environmental missions. Most show relative humidity >80% at the surface in Ida's near environment.

As for your question: Dry air at all levels negatively impacts tropical cyclones, but environmentally, mid-level dry air is more important. Air rising in convection is sourced from near the surface, and if that air is dry then it becomes saturated less quickly when rising --> the air is less buoyant. This is rarely a problem inside a sufficiently strong TC because surface winds drive evaporation that moistens the TC's inflow. If mid-level dry air works into the TC's circulation, though, it can lead to evaporational cooling: falling precipitation will evaporate, taking latent heat out of the air (just as condensation releases latent heat). This cooling also creates negative buoyancy that strengthens downdrafts.

Downdrafts can cut off updrafts, and they also replace warm, moist surface air with cool, dry air. That leads to the original buoyancy problem I pointed out.

[Meteorcane]

Too early to say NOLA is out of the woods, but a landfall nearer to Morgan City or even Terrebone parish, would basically imply "only" TS winds for most of the NOLA area, as unless the windfield expands significantly (this would mostly be due to hard to predict EWRC) the hurricane force winds would stay west of the city proper. Ida would have to go towards the eastern end of the envelope for NOLA to have significant wind impacts.. surge though can still be a factor well east of the center so areas of SE LA (outside of the protection system) and even MS are at risk, even with a center track closer to central LA.

[Hurrilurker]

I shudder to think of what the ceiling for Ida is. Dare I say, I think it might be our first sub-900 storm in years if everything goes wrong.
It's silly but I've always wanted to visit New Orleans someday. I hope I still get the chance with this in mind.

Even if it has absolutely perfect conditions, I think it would run out of time to get that far. I'm guessing 920s at worst is as low as it has time for.

[Craters]

***This is a serious situation***

I hope everyone in SE Louisiana/Coastal MS heeds the warnings and gets the heck out. I cannot emphasize this enough - if there is any doubt, play it safe and evacuate. Don't get caught in a predicament where you need to leave and you can't.

If you are in a mandatory evacuation zone you must leave.

I always tell people that, if you're torn between leaving and staying, you've already made the decision -- leave! You wouldn't be feeling like that in the first place if you thought the situation wasn't threatening.

[skyline385]

I shudder to think of what the ceiling for Ida is. Dare I say, I think it might be our first sub-900 storm in years if everything goes wrong.
It's silly but I've always wanted to visit New Orleans someday. I hope I still get the chance with this in mind.

Sub-900 is too much, it doesnt have the time for that kind of RI and storms only get to sub-900 with a pinhole eye while undergoing explosive intensification. A system with an average sized eye like Ida isnt dropping that low, it would not be able to sustain it...