Major Hurricane Otis

[daz_4]

This deserves its own thread in my opinion. What a disaster and what a failure for models.

 

Edited October 25, 2023 by daz_4

[Gary L]

Absolutely insane this. There will be a lot of questions about why the models just didn't get it right!

Edited October 25, 2023 by Gary L

[matty40s]

Difficult to ascertain why this was such a miss on the forecasting front. There was only one pre landfall flight in.

The damage is catastrophic.

 

[al78]

I have just watched a YouTube clip which had Brian Norcross (an expert at NHC) and one suggestion he had regarding the extreme rapid intensification is a trough in the jet stream that was positioned in a perfect place to vent the top of the hurricane, but far enough away so that it didn't impose strong vertical wind shear over the core. The models completely failed to pick up this perfect coupling of the upper level winds and the storm. Its compact size and warm SSTs also assisted in the intensification.

[SnowBear]

Hurricanes and cyclones are notoriously difficult to predict. We are lucky to be able to forecast as much as we can with them.

Edited October 25, 2023 by SnowBear

[WYorksWeather]

I think the difficulty here is just speed. The fundamental way NWP models work is to ingest data prior to each model run, then use that to project forwards. That data will be ingested as quickly as possible, but clearly there has to be a data cutoff, so e.g. the 0z run will be based on data ingested up to midnight, and by the time it is released, that data is a minimum of six hours out of date. So it was a model fail, but there is a question about how you predict an event like that.

The only way would be if you had enough computational power and observations to run far more frequent model runs. If the major NWP suites ran every 3 hours and had sufficient information updates for that to make sense, there might have been chance to get a warning out. Of course, that's not computationally or observationally feasible at the moment.

Extremely rapid changes like that are always going to be hard to forecast. It's also clear that the current extremely high SSTs have played a significant role.

[matty40s]

 

[matty40s]

 

[lottiekent]

1 hour ago, matty40s said:

 

Just saw this one on Twitter too and found the corresponding street view on Google maps. It’s crazy how much damage has been caused

[AderynCoch]

5 hours ago, al78 said:

I have just watched a YouTube clip which had Brian Norcross (an expert at NHC) and one suggestion he had regarding the extreme rapid intensification is a trough in the jet stream that was positioned in a perfect place to vent the top of the hurricane, but far enough away so that it didn't impose strong vertical wind shear over the core. The models completely failed to pick up this perfect coupling of the upper level winds and the storm. Its compact size and warm SSTs also assisted in the intensification.

I think this is exactly what happened with Ian last year.

An earlier NHC discussion of Otis actually hinted at signs of possible rapid intensification but disregarded it (https://www.nhc.noaa.gov/archive/2023/ep18/ep182023.discus.007.shtml?). They're going to have their work cut out when it comes to doing the post-analysis.

 

Edited October 26, 2023 by AderynCoch

[SnowBear]

I think it's wrong to criticise too much when trying to forecast extreme events like this. What may be said is perhaps we rely too much on models now instead of a good dose of the human eye and intuition. 

No matter how much we try and model the real world there are some events which will be outliers, the sudden volcanic eruption, the earthquake with no warnings, the bombing cyclone and equally the non events which occur too even when the models seem to be saying it's a dead cert. 

There is also the problem where if an alert was given before the system had barely become a TS, and the forecast was for a Cat4-5, and that doesn't materialise, again questions would have been asked. 

It's tricky getting these things right, thankfully we now seem to be getting most right, but we will never get them 100% right. 

 

[matty40s]

 

[Jo Farrow]

Just for reference, the NHC discussion and the update list showing how quickly it reached Cat5

[SnowBear]

10.00am CDT -   70mph -  TS    - 993mb

01.00pm CDT -   80mph - Cat1 - 985mb

04.00pm CDT - 125mph - Cat3 - 960mb

07.00pm CDT - 145mph - Cat4 - 941mb

10.00pm CDT - 160mph - Cat5 - 927mb

01.00am CDT - 165mph - Cat5 - 923mb

Landfall

In 15 hours Otis bombed by 70mb, went from TS to Cat 5,and increased windspeed by 95mph from 70mph to 165mph.

It took 6 hours to go from TS to Cat3, and then 6 hours from Cat3 to Cat5. The length of time to go from TS to Cat5... 12 hours. 

 

[*Stormforce~beka*]

Geeze that's mental! Is that the fastest ever?

[matty40s]

 

[rwtwm]

I stumbled upon this discussion of the intensification this evening. Thought it might be of interest.

Trying to make sense of why Otis exploded en route to Acapulco this week – The Eyewall

THEEYEWALL.COM

---

One-sentence summary Scroll to the bottom for a couple notes on current weather, but in today’s post, I want to try to make some sense of what just happened in Mexico this week. Otis’s …

 

 

[Midlands Ice Age]

Just seen this, and thought it worth while adding a similar bad enough (though less intense) situation, that I found myself in (I think Sept/Oct 1997??)..

I was on a cruise down the west cost of the USA just off the Bhaja(?)  Peninsula heading for Acapulco next morning.

Wonderful hot sun-bathing weather  not a cloud in the sky, until midday,  when the first of two things happened. 

1) We were surrounded by a school of dolphins literally all the way around the ship (at about half a mile) for about an hour and a half. The captain came on and said it was the largest he had ever seen and he estimated 1.500 fish.

2) Clouds started to build up on the mountains to our east . These developed into a large thunderstorm by about 15:00. Spectacular to see. 

Anyway sun bathing continued on board (about 10 miles away), until it was time to go down for dimmer (18:00).

 

During the meal,(about 20:00)  we heard large thunderclaps overhead, and the ship (40.000 tons) started to rock violently, to such an extent that ladies began to scream in the dining room as tables and people were thrown everywhere. We were told it was just a quick storm (and not to panic) which had spread form the coast..

By 22:00 I decided to look outside... Opened  a door on deck 7 (In my DJ!   and was nearly washed away by a wave. Great hilarity amongst my friends/wife. It wasn't funny!, as it was quite scary for me.

Things stayed in this state with a lot of movement on board. So went to bed  early (23:00).

Things got much worse about 01::00 so got up and looked out the porthole....  

To see a water spout/tornado going past about half a mile away surrounded by flashes of lightening. Never seem anything like it before or since.

Went back to sleep!!!!... Woke up next morning and was told we would be late docking because of storm damage on land  (Acapulco).

Long story.....  but then it got interesting.. (for me, a budding weather enthusiast) .

Walking round the ship and bumped into the captain, and asked him what had happened overnight.

He said that there was a TS out to sea,  forecasted  to swing north and then away from the coast. It actually seemed to pull the coastal storms towards it and it (as a result) deepened rapidly. Then it moved straight over us and crashed into the coast about 40 miles north of Acapulco.  That was his report.  Classed as a 2/3 from my memory.

3 people were killed in Acapulco by the storm that night.

The storm killed about 10 -20 people in Mexico (mainly form heavy flooding rains), which continued for 3 days.   I was unaware that it was classed as the worst cyclone to hit Mexico in history as we continued to cruise further south, totally unaware  as to how lucky we had been, as we were virtually ' trapped' by the cyclone when it moved ashore...

So this sort of thing has a precedence...   though not as severe obviously.

I am certain that the mountain based storms (which were spectacular in their own right) was what 'flicked the switch' that day.

Be interested to see if it was the same/ similar situation again. 

To cap it all after going through the Panama canal we got hit by a Caribbean hurricane Cat 1/2, whilst  going into Fort Lauderdale on the last night...

Fantastic for me ,,,,    but not many others were impressed. Best cruise I have ever had ---  Hooked on anything weather  wise for life.. 

Sorry to bore you all with my story...

I often wonder whether the dolphins were trying to warn us>>>>>>>>>

MIA

Edited October 27, 2023 by Midlands Ice Age

[matty40s]

 

[Midlands Ice Age]

No obvious clear reason for the bomb hurricane....

https://www.msn.com/en-gb/weather/topstories/why-did-hurricane-otis-explosively-intensify-off-mexico/ar-AA1iYjVs?ocid=msedgntp&pc=ACTS&cvid=e6ea275e821a4c329905ec9c601d4440&ei=68

Look to the mountains....

MIA

[ANYWEATHER]

On 27/10/2023 at 10:58, Midlands Ice Age said:

Just seen this, and thought it worth while adding a similar bad enough (though less intense) situation, that I found myself in (I think Sept/Oct 1997??)..

I was on a cruise down the west cost of the USA just off the Bhaja(?)  Peninsula heading for Acapulco next morning.

Wonderful hot sun-bathing weather  not a cloud in the sky, until midday,  when the first of two things happened. 

1) We were surrounded by a school of dolphins literally all the way around the ship (at about half a mile) for about an hour and a half. The captain came on and said it was the largest he had ever seen and he estimated 1.500 fish.

2) Clouds started to build up on the mountains to our east . These developed into a large thunderstorm by about 15:00. Spectacular to see. 

Anyway sun bathing continued on board (about 10 miles away), until it was time to go down for dimmer (18:00).

 

During the meal,(about 20:00)  we heard large thunderclaps overhead, and the ship (40.000 tons) started to rock violently, to such an extent that ladies began to scream in the dining room as tables and people were thrown everywhere. We were told it was just a quick storm (and not to panic) which had spread form the coast..

By 22:00 I decided to look outside... Opened  a door on deck 7 (In my DJ!   and was nearly washed away by a wave. Great hilarity amongst my friends/wife. It wasn't funny!, as it was quite scary for me.

Things stayed in this state with a lot of movement on board. So went to bed  early (23:00).

Things got much worse about 01::00 so got up and looked out the porthole....  

To see a water spout/tornado going past about half a mile away surrounded by flashes of lightening. Never seem anything like it before or since.

Went back to sleep!!!!... Woke up next morning and was told we would be late docking because of storm damage on land  (Acapulco).

Long story.....  but then it got interesting.. (for me, a budding weather enthusiast) .

Walking round the ship and bumped into the captain, and asked him what had happened overnight.

He said that there was a TS out to sea,  forecasted  to swing north and then away from the coast. It actually seemed to pull the coastal storms towards it and it (as a result) deepened rapidly. Then it moved straight over us and crashed into the coast about 40 miles north of Acapulco.  That was his report.  Classed as a 2/3 from my memory.

3 people were killed in Acapulco by the storm that night.

The storm killed about 10 -20 people in Mexico (mainly form heavy flooding rains), which continued for 3 days.   I was unaware that it was classed as the worst cyclone to hit Mexico in history as we continued to cruise further south, totally unaware  as to how lucky we had been, as we were virtually ' trapped' by the cyclone when it moved ashore...

So this sort of thing has a precedence...   though not as severe obviously.

I am certain that the mountain based storms (which were spectacular in their own right) was what 'flicked the switch' that day.

Be interested to see if it was the same/ similar situation again. 

To cap it all after going through the Panama canal we got hit by a Caribbean hurricane Cat 1/2, whilst  going into Fort Lauderdale on the last night...

Fantastic for me ,,,,    but not many others were impressed. Best cruise I have ever had ---  Hooked on anything weather  wise for life.. 

Sorry to bore you all with my story...

I often wonder whether the dolphins were trying to warn us>>>>>>>>>

MIA

Thanks for that ,and very interesting to note that the topography of the land may well have more influence than we realise in producing tropical storms and not destroying them!☺

[matty40s]

The on the ground situation is not getting any better in Acapulco. Mexican government seemingly devoid of ideas.

 

[matty40s]

 

[matty40s]

One month on and still struggling to even start the recovery.