SNE "Tropical" Season Discussion 2019

[Bostonseminole]

rainy wed everning commute and everning incoming

[dryslot]

9 minutes ago, Bostonseminole said:

rainy wed everning commute and everning incoming

It was forecast to become a TS but remain offshore, Looks to get some PRE in here though from her, 0.50"-1.00" Weds night into Thurs am here.

[Bostonseminole]

0z gfs has Dorian missing florida and heading for moorehead city NC

[Bostonseminole]

& OTS

[Torch Tiger]

I like this video..60 years ago and it rings very true today

[Modfan]

5 hours ago, Bostonseminole said:

0z gfs has Dorian missing florida and heading for moorehead city NC

Hope so, but still planning like I Might see a Cat 2 in S FL

[Typhoon Tip]

Remarkable agreement among the GFS ensemble 12-member suite provided at PSU E-Wall's web-source, that Dorian will modestly intensify through 120 hours, ending in a position abeam of midriff Florida over the western Bahamas.  

I haven't seen the individual EPS members but the blend is a bit more smeared comparing to the GEFS. Nevertheless, they do average a weakly bounded cyclone in that similar vicinity just E or partially eclipsing land at 120 hours.  

One curious note: both the EPS and the GEPs ( Canadian ensembles ) are attempting to develop what looks similar to an October 'climate low' in the mid Gulf - it's not a real Glossary expression. Anyway, the GEFs do hint of this, but it is much more coherently materialized in these other two ensemble cluster means. I'm curious why they are doing so, but have hypothesis -  

From late September thru early Decembers, it is not uncommon for models to attempt this sort of Gulf of Mexico vortex look. This is classic looking in that regard, the only problem is, vastly earlier than normal.  Nevertheless, I suspect it wise to consider it in the same vane. The rub there is that sometimes quasi-asymmetric systems do sort of bend over initially from baroclinic instability at that time of year, in the Gulf, and then acquire warm symmetry in time. Usually up underneath an early/amplified Perennial North American Pattern ( PNAP ) construct when it does.  I'm wondering if these models are over sensitive; they have been trying at least excuse imaginable on every run to suppress the mid latitude summer ... all summer long, with western heights, and structuring some sort of trough ( usually over blown) back East.  It may be more than muse to consider that entity. Because the vitality and most important, reality of any such object in the Gulf at the beginning of the middle range would play a plausible role in the future of Dorian.

Some of these operational versions attempt to then vaguely Donna-analog Dorian.. Heh, fun entertainment but, too many uncertainties concomitant with tropical modeling at that range, and particularly endemic to the pattern next week is uncertainty.  The introduction of trough in both space and time, inducing that coastal scrape this is all new, and troughs have been tending to flatten in mid ranges --> short range all season long.  Past doesn't dictate the future...  What are we leaving out here ... basically .1% confidence out of 99.9% uncertainty. 

[Typhoon Tip]

By the way ... 

I also am wondering if we may see a more robust period of TWs squirt off western Africa over over the next two weeks at some point.  Not for not, right amid the climate bell-curve anyway. However, there are some clues in play that favor that.   

The orientation/distribution of larger scale UVM tendencies has arrived at a dipolar negative western -central N. Atlantic, with a pervasive and coherent positive tendency over all of the African continent extending east to west along the sub-Saharan TW conduit region.  There are features also embedded in that monsoonal band a bit more robustly now than prior times.  

Supposition/hypothesis... But my personal feeling is that ... yes, Saharan Dust/dry air has been present this year, but frankly, I've monitored that metric spanning some fifteen years and this year has not seemed appreciably worse than any other year - despite other's opinions to the contrary.  Nevertheless, I am willing to nod to that mitigate as being present to some degree.   What really stands out to me as causal in the dearth thus far is the lower TW frequency emerging off of Africa/in transit prior to doing so.   If you mix up weak wave tendencies with SAL mitigation ( and it probably doesn't help that the QBO is statistically out of phase for greater activity this season ) that combination is more likely culpable.   If we are right about a period of stronger TW ejecta off of Africa, that might give the CV region some entertainment value.   

[Hoth]

5 minutes ago, Typhoon Tip said:

By the way ... 

I also am wondering if we may see a more robust period of TWs squirt off western Africa over over the next two weeks at some point.  Not for not, right amid the climate bell-curve anyway. However, there are some clues in play that favor that.   

The orientation/distribution of larger scale UVM tendencies has arrived at a dipolar negative western -central N. Atlantic, with a pervasive and coherent positive tendency over all of the African continent extending east to west along the sub-Saharan TW conduit region.  There are features also embedded in that monsoonal band a bit more robustly now than prior times.  

Supposition/hypothesis... But my personal feeling is that ... yes, Saharan Dust/dry air has been present this year, but frankly, I've monitored that metric spanning some fifteen years and this year has not seemed appreciably worse than any other year - despite other's opinions to the contrary.  Nevertheless, I am willing to nod to that mitigate as being present to some degree.   What really stands out to me as causal in the dearth thus far is the lower TW frequency emerging off of Africa/in transit prior to doing so.   If you mix up weak wave tendencies with SAL mitigation ( and it probably doesn't help that the QBO is statistically out of phase for greater activity this season ) that combination is more likely culpable.   If we are right about a period of stronger TW ejecta off of Africa, that might give the CV region some entertainment value.   

Mike Ventrice noted there is a suppressive Kelvin wave passing over Africa the next few weeks. I know little about such things, but he says that one would expect it to tamp down any wave activity. Who knows. 

[Typhoon Tip]

It's a fine analysis by a couple of mid-Century starched dry pasty robots of early era Television so concomitant with that era of American history.  But man - how egregious was the sexism embedded in that? 

It was amusing enough when the nerd with the high-tech pointer, pants pulled up way too high around a frame that's substantially frail compared to woman of today ( raised by hormone meats no less ), had the audacity to referred to "Donna" as "she."  Ooh.  That pushed up a smile right there!  But the hilarity kicked in when he grinds it. He actually interrupting hims self to say, "And as it - or to be more precise, I should say "she" - " ... 

Man, that was awesome... 

[Typhoon Tip]

13 minutes ago, Hoth said:

Mike Ventrice noted there is a suppressive Kelvin wave passing over Africa the next few weeks. I know little about such things, but he says that one would expect it to tamp down any wave activity. Who knows. 

That may be the case ... absolutely. 

I am an honest genuine poster that qualifies everything with confidence adjectives.   As in, "suppposition/hypothesis" - honestly, I was just basing it on observations now.  Perhaps V is deducing modeling - I mean duh, he says 'next two weeks'    I also did wonder if there was a large K-wave event rippling through the hemisphere when I noted the dipole construction of UVM tendencies.  I didn't get into it because unfortunately, folks tl;dr everything these days in lieu of instant gratification from the psychotropic addiction of media spectra, and if they are not getting overly stimulated NOW they move on.  Cute ancillary aspect of high- tech that is destroying the "enjoyment" much less virtuosity of a good read - blah blah...  Conceding to forces one cannot control - I just kept imagining to my self,  any such event ripple passing through and the current dipole might tend to reverse?  Then, residual ( because they were initially robust  ) TW then time with a better Atlantic.  See... KW don't absolutely mean anything. We can work with them here.  ha

Actually since I posted that I saw the Euro spins up a TC almost immediately leaving Africa on D 9 ... interesting or not

[Bostonseminole]

Dorian looking heathier.. 65knots winds on latest pass.. wonder if it misses PR also.. seems further east than models

[Typhoon Tip]

16 minutes ago, Bostonseminole said:

Dorian looking heathier.. 65knots winds on latest pass.. wonder if it misses PR also.. seems further east than models

Thought so too - 

It may be why some of the ensemble members and the actual tropical suite's shown some recent right bias in the track guidance.  TPC didn't seem to comment on it as of 5am but there 11 should be out shortly -

 

[Torch Tiger]

Yorian

Fixes from the reconnaissance plane indicate that Dorian has been
moving toward the northwest or 315 degrees at 11 kt. The cyclone is
heading toward a weakness in the Atlantic subtropical ridge, and
this motion should continue for the next 2 to 3 days. However, after
that time, all global models build a robust ridge over the western
Atlantic, and this flow pattern should force Dorian to turn more
to the west-northwest toward Florida and the southeast coast of the
United States. All indications are that by this Labor Day weekend, a
powerful hurricane will be near the Florida or southeastern coast of
the United States. The new NHC track forecast is not significantly
different from the previous one, and it very closely follows the
multi-model consensus TVCA and the HCCA. Users are reminded not to
focus on the exact forecast track, as the average 5-day track error
is around 200 miles.

 

[dryslot]

Looks like the heading is more NNW as well on IR, May be starting to form an eye too.

[Bostonseminole]

Michael Ventrice

@MJVentrice

 

Latest SHIPS diagnostic message on Tropical Storm #Dorian: There's an abnormally high (44%) chance of rapid intensification of 45kt in 36 hours. This is 10 times higher than the climatological mean. Bold stance.

[Typhoon Tip]

Wow,

"... The NHC foreast is more aggressive than the previous one, and brings Dorian to category 3 intensity by the end of the period. This forecast very closely follows the intensity consensus, the HCCA model, and the SHIPS guidance...."

Although, I have noticed a tendency by NHC to 'enhance wording' if not biasing toward more intensity when these TCs start nearing civility - probably for the better PR -wise.  I mean, it's been a dearthy season of sitcom television and iPhone distractions.  Hard to image after Maria and so forth that society would be complacent, but that happens.  Short memories.   Not to mention, these sort of ephemeral natural disasters are obscuring these days behind the growing specter of GW ...

Still, they have the guidance and it's ligit - either way. That region near the Bahamas - as modeled in means from multiple sourcing - looks superb for strengthening.

 

 

[Cyclone-68]

I guess we have our new headlining news story for the holiday weekend in any case 

[Torch Tiger]

59 minutes ago, Cyclone-68 said:

I guess we have our new headlining news story for the holiday weekend in any case 

This is going to be awesome, hopefully it stalls right over Orlando for a few days

[dryslot]

Dorian looking healthier on IR.

[Typhoon Tip]

What's peculiar to me is that the entire suite of various Global numerical models did not initialize Dorian very well on the 12z guidance cycle ... yet, they all take it through robust strengthening over a 24 to 36 hour period beginning pretty much now through tomorrow night.  

I dunno if there's much merit to the following thinking but that "seems" sort of dire to me - as in ...this means that an even deeper/structurally evolved entity entering that same favorable domain space ... might attain a status that exceeds the models by the time we get to that D4/5 window and this is knocking on the door ... 

[Typhoon Tip]

looks like an eye on last couple of rad scans... 

[Damage In Tolland]

Seems destined for cat 4 LF

[nutmegfriar]

On which coast?

[Typhoon Tip]

24 minutes ago, Damage In Tolland said:

Seems destined for cat 4 LF

Man... I'll tell yeah... sea-level rise is already becoming a management problem in Miami at times of 'fair-weather' high tides.  

 

that would be                             bad

[STILL N OF PIKE]

On 8/24/2019 at 1:13 PM, STILL N OF PIKE said:

Tropical depression 5 ...forecast to become a hurricane as it crosses NE Caribbean 

that is an example of the POLITICS of forecasting . Caribbean  Looks hostile l and would be lucky to make it thru as Tropical storm but IMO bc it’s close to islands Stewart is going with HRFW? And Cat 1. Good luck 

My worst post 

my bad 

This storm looks frightening as it has shifted so Far East that it went from crossing Hispaniola to going currently East of Puerto Rico as it strengthens . 

[STILL N OF PIKE]

Interesting to see if the ridge orientation 72-120 hours out takes on a pure W-E orientation or even possibly shifts to create a WSW motion . Also what latitude it’s at when it turns west and feels the ridge makes all the difference 

The fact this barely entered Caribbean really helped this become a disaster in THe making (avoiding land) and less favorable conditions 

[Bostonseminole]

11 minutes ago, STILL N OF PIKE said:

Interesting to see if the ridge orientation 72-120 hours out takes on a pure W-E orientation or even possibly shifts to create a WSW motion . Also what latitude it’s at when it turns west and feels the ridge makes all the difference 

The fact this barely entered Caribbean really helped this become a disaster in THe making (avoiding land) and less favorable conditions 

yeap, it took the perfect tract to avoid any disruption, only hope is the environment is not as good as forecasted as it nears FL.. I also agree this might jog WSW at some point, I think anywhere from Daytona Beach to Key West is still fair game.

[STILL N OF PIKE]

1 minute ago, Bostonseminole said:

yeap, it took the perfect tract to avoid any disruption, only hope is the environment is not as good as forecasted as it nears FL.. I also agree this might jog WSW at some point, I think anywhere from Daytona Beach to Key West is still fair game.

Ya 

i was trying to see what size it’s forecast to be in 96-120 hours 

it’s tiny now

[Typhoon Tip]

21 minutes ago, STILL N OF PIKE said:

Interesting to see if the ridge orientation 72-120 hours out takes on a pure W-E orientation or even possibly shifts to create a WSW motion . Also what latitude it’s at when it turns west and feels the ridge makes all the difference 

The fact this barely entered Caribbean really helped this become a disaster in THe making (avoiding land) and less favorable conditions 

Concerned about Miami  ...  

Here's the deal - 

Dorian is likely to exceed expectations for intensity guidance.  I've just seen this kind of beat before...where the models don't even initialize a system beyond depression, when it reality it's nearing hurrican strength ...yet they still collectively suggest near rapid intensification is plausible despite the weak bias out of the gate ( 12z suite).    It's moving up into a region that is going to be nothing but improving for TC structure/genesis.  It seems the models are tapping into this latter circumstance proficiently enough, but are not correctly accessing the inertia Dorian already had established.   That is troublesome...  

But mostly, it is the excessive thermal cline integration of ocean heat content it is moving toward, combine with superior shear - lack there off - that should have folks' attention. 

The reason this sticks Miami out like a sore thumb - despite the present concensus N of that latitude, is because strong/strengthening hurricanes gaining size, can synergistically enhance resistance to polarward motion because they "create their own environment."  Basically what is taking place when that happens is ... the outflow ring of the cyclone begins to elevate surface pressure...as well as breaks down steering fields on the polarward size of the cyclone, and the tracks can sometimes bend back west when that happens.  It may not be statistically entirely obvious that is what is happening, either, because of the surrounding synoptics are strong enough those forcing will damp the effect out - it's more like an effectiveness when other factors are relatively negligible, the cane will "moat" its self off/tend to do so..

I see Dorian moving into an environment of superior development, that is breaking down synoptically ...which might render it to a west bump out there in time.   Something to think about. It's a big maybe  and not a prediction... but you do have a bomb potentially hear, and one moving into temporarily induced deeper layer COL look to the troposphere, and I could see that do weird things.