ATL: BERYL - Post-Tropical - Discussion

[GCANE]

Amazing how the high TPW air from the mid-Amazon basin to the coast of South America has suddenly deepened.
TD2 should start to entrain this late weekend.
A huge amount of fuel will pour in.

https://tropic.ssec.wisc.edu/real-time/ ... anim=html5

[Tammster]

Don't have a great feeling about the islands there, Barbados, St. Lucia, etc. Hope these folks take it seriously, now would be good. There's Cricket World Cup finals going on this weekend there too in Barbados.

 https://twitter.com/burgwx/status/1806797479746167119

I'm in Barbados now (from FL). At home everyone would be boarding up, selling out the grocery stores and filling up their cars. Here, everyone is basically treating as just a little storm. Very bizarre.


Sent from my iPhone using Tapatalk

[ConvergenceZone]

I think the NHC is too high with intensity and too far north with the track. They're following consensus, which, I think, is too far north due to the GFS input. Same thing as with Idalia last year, the GFS operational and ensembles were into the western FL panhandle, making the TVCN/TVCC point the hurricane at Apalachicola. There should be a building ridge north of the storm by days 4-5, which will likely turn it due west or south of west. Still thinking Belize, though maybe northern Belize. My coworker thinks it may enter the Caribbean as far south as Grenada, as models are almost always too far north in situations like this. NHC will likely be adjusting their track southward with time.

I like your analysis and reasoning. Now I know some will say, yea but the stronger it gets, the more poleward it goes. And while that's true in the short-term and in certain atmospheric conditions, If there's a blocking ridge above it(like what's expected to develop in the Gulf), then it's still going to bock it from moving north, whether the storm is 75 mph or 150 mph, it doesn't matter. A wall is a wall and it will still steer the storm under forecasted wall/ridge, thus the Mexico landfall that you are predicting.

[GCANE]

AF300 will be landing in St Croix shortly

Some layer analysis will be helpful, NHC still holding this as a Hurricane near Jamaica so the TUTT evolution is going to be important as well.

I've been looking at 250mb the past few days.
Basically, no shear all the way thru the Carib following the standard Carib runner track.
Highly likely this will go thru the Yucatan Channel.

The big feature that I have been talking about and the models are very consistent with is an UL Trough developing north of Hawaii when TD2 is in the Mid Carib.
The trough has a well-defined Anti-Cyclonic Rossby Wave Break (AWRB).
We have seen over the years, many times when a TC gets in an ARWB, they rapidly develop to high-end major cane.

The trough will move east as TD2 moves west.
It's a possibility they could interact in the GoM, which would lead to rapid intensification and a curve of TD2 north.

Hopefully the timing is off and we are spared.
Going to be watching very closely.

[Dougiefresh]

Don't have a great feeling about the islands there, Barbados, St. Lucia, etc. Hope these folks take it seriously, now would be good. There's Cricket World Cup finals going on this weekend there too in Barbados.

https://twitter.com/burgwx/status/1806797479746167119

I'm in Barbados now (from FL). At home everyone would be boarding up, selling out the grocery stores and filling up their cars. Here, everyone is basically treating as just a little storm. Very bizarre.


Sent from my iPhone using Tapatalk

That's due to a few factors. Tomorrow is a world cup final so most people's minds are not on the weather but on the final. Secondly, and probably to our detriment, we are a very laid back group of people with the mentality that 'God is a Bajan' and that nothing bad will happen to us. However, when all signs start pointing to something imminent happening, we flock in droves to the supermarkets and hardware stores to stock up. If you're around on Sunday, do not go to the supermarket.

It also probably doesn't help that our Met service takes a more conservative approach as they have been burned in the past.

[Nimbus]

Don't have a great feeling about the islands there, Barbados, St. Lucia, etc. Hope these folks take it seriously, now would be good. There's Cricket World Cup finals going on this weekend there too in Barbados.

https://twitter.com/burgwx/status/1806797479746167119

I'm in Barbados now (from FL). At home everyone would be boarding up, selling out the grocery stores and filling up their cars. Here, everyone is basically treating as just a little storm. Very bizarre.


Sent from my iPhone using Tapatalk

A major hurricane changes the upper air dynamics considerably so the model evolution will be important as this passes through the islands. I'm a sucker for a big red blob like most of us, but we haven't any recon data yet so too early to be sure. Inflow from a rapidly deepening hurricane could pull in some dry air from the SAL just to the north of the track for example.

[storm_in_a_teacup]

AF300 will be landing in St Croix shortly

Some layer analysis will be helpful, NHC still holding this as a Hurricane near Jamaica so the TUTT evolution is going to be important as well.

I've been looking at 250mb the past few days.
Basically, no shear all the way thru the Carib following the standard Carib runner track.
Highly likely this will go thru the Yucatan Channel.

The big feature that I have been talking about and the models are very consistent with is an UL Trough developing north of Hawaii when TD2 is in the Mid Carib.
The trough has a well-defined Anti-Cyclonic Rossby Wave Break (AWRB).
We have seen over the years, many times when a TC gets in an ARWB, they rapidly develop to high-end major cane.

The trough will move east as TD2 moves west.
It's a possibility they could interact in the GoM, which would lead to rapid intensification and a curve of TD2 north.

Hopefully the timing is off and we are spared.
Going to be watching very closely.

Why does an ARWB intensify a hurricane? Does it help the upper anticyclone vent or something like that?

[GCANE]

Sorry, BTW that TUTT is actually the edge effect of another ARWB from an UL Trough on the west coast.
It has significantly weakened the past couple days in the models.
It is pretty much moot at this point.

[weeniepatrol]

Taking an area-averaged sounding from the currently-disseminating 18z GFS, a few things stick out:

PWAT 2.3 inches

nearly saturated vertical column from the surface to tropopause

Tropopause seems to be located around 150mb. Seems very high for the Atlantic; no wonder convection is so cold.





On the flip side, the mid-shear that seems to always plague these early-season MDR systems is present. 700-300mb easterlies are 10-15 kt faster than surface/200mb flow, pushing convection slightly away from the surface center.

This shows up well on the NHC map; the center of Two is placed on the eastern edge of the thunderstorms.



I look forward to recon particularly for checking the vertical alignment of Two. Once it aligns itself, it should be off to the races.

[Kazmit]

Honestly very surprising the NHC went as high as they did. They're usually quite conservative, especially on the first advisory. Not to mention, climatology says this thing gets shredded the second it enters the Caribbean Sea. Then again, climatology is changing.

[GCANE]

Some layer analysis will be helpful, NHC still holding this as a Hurricane near Jamaica so the TUTT evolution is going to be important as well.

I've been looking at 250mb the past few days.
Basically, no shear all the way thru the Carib following the standard Carib runner track.
Highly likely this will go thru the Yucatan Channel.

The big feature that I have been talking about and the models are very consistent with is an UL Trough developing north of Hawaii when TD2 is in the Mid Carib.
The trough has a well-defined Anti-Cyclonic Rossby Wave Break (AWRB).
We have seen over the years, many times when a TC gets in an ARWB, they rapidly develop to high-end major cane.

The trough will move east as TD2 moves west.
It's a possibility they could interact in the GoM, which would lead to rapid intensification and a curve of TD2 north.

Hopefully the timing is off and we are spared.
Going to be watching very closely.

Why does an ARWB intensify a hurricane? Does it help the upper anticyclone vent or something like that?

it is in itself an anticyclone created on the SE side of the trough.
As you know, an anticyclone vents a TC.

[GCANE]

If this doesn't calm down in a few hours, I'd say we have a beast on our hands,

[abajan]

Don't have a great feeling about the islands there, Barbados, St. Lucia, etc. Hope these folks take it seriously, now would be good. There's Cricket World Cup finals going on this weekend there too in Barbados.

You're quite right about the T20 Cricket World Cup final. Cricket is a big deal in the West Indies and I fear many of my compatriots will be caught off-guard because they're more focused on the match tomorrow than preparing for the weather.

[wxman57]

Honestly very surprising the NHC went as high as they did. They're usually quite conservative, especially on the first advisory. Not to mention, climatology says this thing gets shredded the second it enters the Caribbean Sea. Then again, climatology is changing.

I think they're believing the GFS too much. I monitor all basins, and the GFS is way too strong everywhere.

[Stratton23]

I think the intensity forecast is absolutely reasonable, given that the hurricane models are even more aggressive , i think its fair that they went with a forecast below those even more aggressive runs, its going to have a solid 48-72 hours where it could be intensifying at a good clip to maybe even rapidly at times, the ceiling for this would be a low end cat 3, but it doesnt really matter too much st this point

[aspen]

Honestly very surprising the NHC went as high as they did. They're usually quite conservative, especially on the first advisory. Not to mention, climatology says this thing gets shredded the second it enters the Caribbean Sea. Then again, climatology is changing.

I think they're believing the GFS too much. I monitor all basins, and the GFS is way too strong everywhere.

Plus, many of the modes (especially the HWRF) tend to over-estimate June/July systems in the western MDR/eastern Caribbean. It happened with Gonzalo ‘20, Elsa ‘21, Bonnie ‘22, and Bret ‘23. I’d say odds are good it happens again.

[USTropics]

I think the NHC is too high with intensity and too far north with the track. They're following consensus, which, I think, is too far north due to the GFS input. Same thing as with Idalia last year, the GFS operational and ensembles were into the western FL panhandle, making the TVCN/TVCC point the hurricane at Apalachicola. There should be a building ridge north of the storm by days 4-5, which will likely turn it due west or south of west. Still thinking Belize, though maybe northern Belize. My coworker thinks it may enter the Caribbean as far south as Grenada, as models are almost always too far north in situations like this. NHC will likely be adjusting their track southward with time.

I like your analysis and reasoning. Now I know some will say, yea but the stronger it gets, the more poleward it goes. And while that's true in the short-term and in certain atmospheric conditions, If there's a blocking ridge above it(like what's expected to develop in the Gulf), then it's still going to bock it from moving north, whether the storm is 75 mph or 150 mph, it doesn't matter. A wall is a wall and it will still steer the storm under forecasted wall/ridge, thus the Mexico landfall that you are predicting.

But what if the wall develops a whole in it? (going to need some spackle)

I'm not sold on a straight westward track into Central America (although I would still lean that way given current guidance). This is key from the NHC discussion:

The system might gain a little more latitude toward the end of the forecast period when it nears a weakness in the subtropical ridge.

If you look at the trend of the past 4 runs of the ECMWF and GFS runs, there is a more pronounced weakness in the past few runs:

[Woofde]

Honestly very surprising the NHC went as high as they did. They're usually quite conservative, especially on the first advisory. Not to mention, climatology says this thing gets shredded the second it enters the Caribbean Sea. Then again, climatology is changing.

I think they're believing the GFS too much. I monitor all basins, and the GFS is way too strong everywhere.

Plus, many of the modes (especially the HWRF) tend to over-estimate June/July systems in the western MDR/eastern Caribbean. It happened with Gonzalo ‘20, Elsa ‘21, Bonnie ‘22, and Bret ‘23. I’d say odds are good it happens again.

It could be a repeat of the past. Though this is the warmest we've ever seen this area in June. 2c more than the average on the surface, and far more deep heat as well. The only comparable year in heat was last year, but the el nino makes for a bad comparison. If any year is going to overperform past setups, I think this is a good contender.

[GCANE]

Something is not normal here,
Major intensification under way.
A large hot spot has developed in the middle of the deep convection.
Clearly seeing this on IR.
All south of 10N.
Hate to say it, but 2005 was also a season where normal intensification playbooks were thrown out the window.

[GCANE]

First core thermodynamic analysis.
A cold pool below a slight warm core.
Indicative off a strong lapse rate and development of cyclonic circulation through the lower tropopause.

https://tropic.ssec.wisc.edu/real-time/ ... _xsect.gif