Hurricane Ida

[OhYouBadBadKitten]

She is one scary beast. It looks like Louisianna is in for a really bad time on the anniversary of Katrina.

At the moment she is cat 4, still explosively deepening with no signs of an eyewall replacement cycle. Radar is showing an area of sustained winds of over 140 mph, though officially they are still 130mph.

Seems there's some maintenance issues with the hurricane hunter planes, so it could be a few hours before another fly through is done. An astonishingly bad time to not have that data.

Its worrying.

Houma has been hit by the inner eye wall.

Reports of a levee in the Braithewaite area has been overtopped and emergency flash flood warnings for the area to get to higher ground have been issued.

Has it OYBBK? Damn, I really wanted to see the middle bit, I was consoling myself that the radar I looked at made it seem like the eye had gone crazy and hit a left, did look like artefact to be honest. Does it look like everyone was safe, am I right in thinking there are crazy fast wind speeds before the calm middle hits? I'm sure there will be lots of posts of it online tomorrow.

Oh no Red, fingers crossed everyone stays safe.

You can see how the inner eyewall grazes Houma here.
twitter.com/mrjamescosgrove/status/1432099972846178306?s=21

Yes, some crazy winds on that outer edge, but especially on the SW side.

The footage on twitter is astonishing! I hope that the evacuation order has been heeded and there is no loss of life.

Its looking bad on Grand Isle. There were 52 people who stayed (including first responders - i believe most of the others were family of first responders). There are reports that some of these have called for help (there obviously isn't any available at present).

The police chief has been on the weather channel saying the roof of the police building which was supposed to withstand 200mph was coming off and there was 4ft of water outside. He didn't know if the building could hold up for another 3hrs. Apparently 15 people in the building.

The police chief had previously reported that the wind gauge clocked 148 mph winds - and then the gauge broke.

It sounds as if they've been going through hell. Looking at videos, how could anyone survive that?

Dan Lindsey @DanLindsey77
I count 4 mesovortices rotating around the outer portion of #Ida's eye, evident in the low cloud field. And the eye is now completely over land! I don't think I've seen this before with a storm over land.

twitter.com/DanLindsey77/status/1432081038830800896
Link to tweet with video which shows what this looks like.

en.wikipedia.org/wiki/Mesovortex

An eyewall mesovortex is a small-scale rotational feature found in an eyewall of an intense tropical cyclone. Eyewall mesovortices are similar, in principle, to small "suction vortices" often observed in multiple-vortex tornadoes.[citation needed] In these vortices, wind speed can be up to 10% higher than in the rest of the eyewall. Eyewall mesovortices are most common during periods of intensification in tropical cyclones.

Eyewall mesovortices often exhibit unusual behavior in tropical cyclones. They usually revolve around the low pressure center, but sometimes they remain stationary. Eyewall mesovortices have even been documented to cross the eye of a storm. These phenomena have been documented observationally,[ experimentally, and theoretically.

Eyewall mesovortices are a significant factor in the formation of tornadoes after tropical cyclone landfall. Mesovortices can spawn rotation in individual thunderstorms (a mesocyclone), which leads to tornadic activity. At landfall, friction is generated between the circulation of the tropical cyclone and land. This can allow the mesovortices to descend to the surface, causing large outbreaks of tornadoes.

I think this falls under the classification very bad

Its thought to be because of much of the area is marsh land so shallow warm water still fuelling the storm.

On 15 September 1989, during observations for Hurricane Hugo, Hunter NOAA42 accidentally flew through an eyewall mesovortex measuring 320 km/h (200 mph) and experienced crippling G-forces of +5.8Gs and -3.7Gs. The winds ripped off the propeller de-icing boot and pushed the flight down to a perilous 1000 ft above sea level. The ruggedized Lockheed WP-3D Orion was only designed for a maximum of +3.5Gs and −1G.^

I'd normally associate these mesovortices with a rapidly deepening storm over the sea. Ida barely weakened at all as she made landfall. I wonder if when analysed she will be recategorised as Cat 5 storm.

Reports of the Mississippi going backwards and a massive storm surge on Lake Pontchartrain (its actually an estuary).

The eye wall is just hitting the area now. Theres some footage of the surge at LaPlace, and it looks huge. LaPlace is 25miles West of New Orleans (roughly halfway between New Orleans and Baton Rogue).

She's down to a cat 3 now. Doesn't really make her much less, if any, less dangerous though.

Oh wow, that might explain what I've been seeing on the radar, it looked like almost multiple fractals on the eye wall. Scary.

From what im reading they are less concerned about storm surge on the whole with this one compared with Katrina (partly because the levees have been reinforced so much since), not to say the storm surge isnt causing massive devastation. It sounds like the winds with Ida are the thing thats causing massive issues. An oil rig has been cut lose by the winds already and there are considerable concerns about the chemical factories in the direct path of Ida having issues.

There are reports that a generator at one hospital has now failed and icu patients have had to be moved and manually ventilated.

Sounds like its going to be a bad night.

OYBBK, DH just said we got the tail end if Katrina about 2 weeks later.

I've just checked the metoffice forecasts and for the 13th - 26th September we have
The influence of tropical storm activity brings some uncertainty to this period. An unsettled spell is most likely for the middle of September, the focus for this toward the northwest of the UK, with the south and southeast perhaps holding on to drier weather.

I take it this is the back end of Ida?

@SimonedeBeauvoirscat the liveblog you are thinking of was interdictor on Livejournal. It was still there a couple of years ago when I last looked. I remember reading in real time. My friend lived in Bywater which was heavily affected and she hadn't evacuated. She didn't get out until around 5th September and I was worried sick. She left with her dog the clothes on her back and her laptop with her thesis on it.
She still lives in New Orleans but not quite so close to the levees. She isn't evacuating this time either.

Steve Caparotta @steveWAFB
WOW. Ship at Port Fourchon reported sustained wind of 149 mph and a gust to 172 mph. #Ida #LAwx

Huge floods in LaPlace. Footage from a camera placed 10ft above ground shows water close to camera level. Twitter is full of requests for help with addresses in the area.

Fears are growing for those who stayed on Grand Isle but communications may be down.

Reports of fires in Kenner.

I've seen very little online so far from Houma or Larose since the storm chasers there went to ground just before the eyewall hit. They were saying it was going to be BAD.

Texas Storm Chasers @TxStormChasers
642AM: Our chase team is abandoning/evacuating Larose, LA and heading north. This town is not survivable in a high-end Cat 4+ hurricane. Town is "sticks and tin" (wood and tin construction) and will be full of flying debris. Lots of folks did not evacuate and are still in town.

For context Ida appears to have recorded wind speeds 7mph short of cat 5 at land fall. Katrina was cat 3 at land fall.

Morning all. dh is snoring his head off, so I've been catching up one fingered so as not to disturb him.

She's a Cat 1 now, moving slowly. LaPlace looks badly hit doesn't it. And New Orleans has no power after a transmission tower came down into the Mississippi.

The Atlantic is pretty busy Red so I'll have to dig a bit deeper.
It could be remnants of a few storms. There's a new potential trouble maker brewing up right now.
www.nhc.noaa.gov/gtwo.php?basin=atlc&fdays=5

Storm surge although devastating again for the places it hit this time is less of an issue than it was for Katrina also because Katrina was bigger, slower and her position was worse for NOLA

I’ve been in a Cat 5 hurricane in Jamaica. It was intense. Hope this isn’t as bad as they are thinking when it hits

I bet it was StormBaby.

I used to live in st louis.
whilst the hurricanes where merely storms there (enough to bring some tree branches electricity poles down), the flooding at the mississippi & missouri river due to the river being blocked up by the floods at the coast could be quite scary.

I hope the damage turns out to be manageable and that people will be able to rebuilt their lives again.

Its hard to imagine what the Mississippi flooding is going to be like.

The river briefly had a negative discharge as it reversed in flow.

One person on twitter put this into context:

The Mississippi River is 200’ deep at New Orleans, and a half mile wide.

That’s a wall of water as tall as a skyscraper and as wide as a city block, with 2,000 miles of water behind it.

If the water wasn't discharging into the sea, then the entire river at this point was effectively going inland.

Hence the huge floods at Leplace and the surrounding areas as they became the Mississippi.

Even before reports and pictures come in, its got to be complete devastation there.

I read that Hurricane Ida stayed as a category 4 storm for 6 hours after making landfall.

I can't imagine the terror that they are going through in LaPlace. I've been reading tweets from volunteer rescue organisations whose boats are flipping in the wind before they can get close. This night must seem so very long and dark to them.