Atlantic Tropical Action 2013

[wxmx]

My natural optimism probably won't work out on either a local rainmaker or a chase-worthy storm.  But my optimism on a Gulf lemon from over a week ago has at least been rewarded.

 

BTW, I think it runs out of time, but the upper low in the middle of the Gulf is a more interesting feature than the actual lemon.  CIMSS suggests it has started to work down to 700 mb.  It should be inland within 2 days and won't have time to get too interesting.

It looks like it will form another surface trough before running ashore as well. Those troughs plus whatever might become from the NW Carib/GoM feature would bring copious rains to Tamaulipas and Deep S TX

[Ed Lizard]

Next week's BoC system looks like it will actually be just far enough North to experience less than optimal 200 mb flow (not shown) and limited 500-700 mb moisture on the West side (also not shown).  About glass half full on a cherry/TD, but quarter full on anything over a 45 knot minimal storm.

 

Shown is displacement of 850 mb center and 500 mb center as forecast by GFS.  As an aside, Canadian and NavGEM would have a named system, Canadian less than a hurricane headed for the Northern Gulf coast, NavGem at 180 hours in (per PSU 4 panel) system probably near a hurricane already, under near perfect conditions of shear, in a moist environment and 500 mb steering that looks like it should steer it NW towards Texas, extrapolated to a turn probably towards Louisiana from shape of the ridge.

 

Higher res Canadan global, still seems prone to ersatz systems, but no longer TD to Cat 4 in 2 day weeniebait.  NavGEM may be the new weenie model.

 

Further aside, GFS at hour 192 looks favorable for potential long trackers that could develop between about 40 and 60W and not automatically fish.  500 mb pattern looks good for the tracks, and in deep tropics, shear looks to be light and actually Easterly, and forecast PW looking decent.  No glass something full probs yet but late August into early September/Labor Day, strictly based on GFS, looks interesting. 

 

 

Hope some of the Albany people weigh in on that again soon.  I'm rather light, even as an amateur, on that.

[Amped]

 

 

This is all I have to look at. It is not very enthusiastic about the CV season. Disappointing for the fish.    It does show activity heating up near the east coast in the first week in September where something could make landfall.

[HurricaneJosh]

I don't know why folks are so hung up on a good Cape Verde system.  They fish or die 99% of the time.  You can count the memorable USA impacts from CV systems on the fingers of both hands.

[Ed Lizard]

I don't know why folks are so hung up on a good Cape Verde system.  They fish or die 99% of the time.  You can count the memorable USA impacts from CV systems on the fingers of both hands.

 

I haven't seen many Cape Verde type posts in the last few days.  Not sure if my 40-60W comment (including 'not automatic fish') triggered that.

 

 

If we're not counting dry windstorms like Lee, the last TC to really affect my sensible weather was classified a TC just East of 40W.  Which is still 15 degrees West of the actual Cape Verdes.  So, not technically a Cape Verde storm, but a long tracker.  And everyone who grew up on Long Island heard about the CV storm that didn't fish or die.

 

Reminds me, a nice wave coming off Africa now, Euro tracks it as a closed low for a couple of days before it weakens.  And, from a strictly landfalling and chaseable storm perspective, slow development is the way to go.  And while I didn't say that, post about GFS at 192 having a look favorable for long trackers was about storms that don't fish or die.

 

 

If that wasn't directed at me and I'm being oversensitive, than, sorry.

[Srain]

I don't know why folks are so hung up on a good Cape Verde system.  They fish or die 99% of the time.  You can count the memorable USA impacts from CV systems on the fingers of both hands.

I agree. Give me a good old 'Carla Cradle' genesis and even a rare BoC system that you don't have to track for 2 weeks only to watch turn N and NE any day. But that`s just me.

[Superstorm93]

Pretty safe to say that there won't be any decent EATL/CATL action for a while...

 

To not have a single hurricane through mid-late August would be interesting. 

 

[andyhb]

Pretty safe to say that there won't be any decent EATL/CATL action for a while...

 

To not have a hurricane through mid-late August would be interesting. 

 

That's...

 

not pretty...

[tmagan]

Imagine seeing the last paragraph in an NHC discussion today.

[Derecho!]

Imagine seeing the last paragraph in an NHC discussion today.

frederic_discussion.jpg

 

Back when I was first on the internet in 1995 the advisories on the internet had the same or similar language.

[Amped]

That's...

 

not pretty...

Not if you like TC development chances. I actually think that product looks kind of artistic in it's own way. It's just a giant white death cloud dancing around the Sahara. I wonder how people live there?

 

Edit:

Also that claims to be a goes product, however it appears to be seeing into the future somaybe it's a model simulated geos product? Doesn't have a model listed on it.

[wxmx]

Not a bad forecast track for 1979

[Ed Lizard]

Back when I was first on the internet in 1995 the advisories on the internet had the same or similar language.

 

It predicts into the future, (out to 120 hours) and has a spectral truncation number on the bottom, it is a forecast product.

[Superstorm93]

Not if you like TC development chances. I actually think that product looks kind of artistic in it's own way. It's just a giant white death cloud dancing around the Sahara. I wonder how people live there?

 

Edit:

Also that claims to be a goes product, however it appears to be seeing into the future somaybe it's a model simulated geos product? Doesn't have a model listed on it.

 

It's the NASA GEOS-5 model (note the O and E placement lol) 

 

http://gmao.gsfc.nasa.gov/forecasts/

 

EDIT: I find it rather sad that Saharan dust is being tracked as opposed to any type of tropical system. 

[wxmx]

Raising the odds for possible mischief in the GoM (via NW Caribbean) to moderate. Reason is that models are still showing it to varying degrees (Euro has very weak depiction of something, so that's still concerning), and that land interaction appears to have lessened somewhat wrt Central America. Long wave trough weakening/splitting ridging in the N GoM adds complexity, and it looks there might be some troubles with upper air support if trough digs just enough to impart shear. Favored track would be NW Caribbean/Mexican Yucatan peninsula/and then W between latitudes 18N and 25N for now.

[Ed Lizard]

It's the NASA GEOS-5 model (note the O and E placement lol) 

 

http://gmao.gsfc.nasa.gov/forecasts/

 

EDIT: I find it rather sad that Saharan dust is being tracked as opposed to any type of tropical system. 

 

 

I shall have to enquire of the moderating staff whether the NASA GEOS model is frowned upon.  I specifically did not post weenie dream 12Z FIM8.

[Ed Lizard]

Raising the odds for possible mischief in the GoM (via NW Caribbean) to moderate. Reason is that models are still showing it to varying degrees (Euro has very weak depiction of something, so that's still concerning), and that land interaction appears to have lessened somewhat wrt Central America. Long wave trough weakening/splitting ridging in the N GoM adds complexity, and it looks there might be some troubles with upper air support if trough digs just enough to impart shear. Favored track would be NW Caribbean/Mexican Yucatan peninsula/and then W between latitudes 18N and 25N for now.

 

If that does develop, it might not be in a huge rush to move into Mexico judging by 700 mb and 500 mb heights, it is South of a weakness in the ridge.  Depends on where it comes off the Yucatan, the random GEFS ensemble member/FIM run with a turn to the North and then Northeast doesn't seem completely impossible, or, more likely, possibly two full days crossing the Gulf over some rather decent heat potential.  Could be situated under a weak anticyclone at 200 mb and 250 mb.  My natural optimism, if there was a coherent system approaching the coast neat Tampico, it'd be under very light upper flow while a forecast 35 knot flow over South Texas could be ventilating it.

 

You and Adam are more likely to be correct, but I can't help seeing the potential silver linings.

[wxmx]

If that does develop, it might not be in a huge rush to move into Mexico judging by 700 mb and 500 mb heights, it is South of a weakness in the ridge.  Depends on where it comes off the Yucatan, the random GEFS ensemble member/FIM run with a turn to the North and then Northeast doesn't seem completely impossible, or, more likely, possibly two full days crossing the Gulf over some rather decent heat potential.  Could be situated under a weak anticyclone at 200 mb and 250 mb.  My natural optimism, if there was a coherent system approaching the coast neat Tampico, it'd be under very light upper flow while a forecast 35 knot flow over South Texas could be ventilating it.

 

You and Adam are more likely to be correct, but I can't help seeing the potential silver linings.

Yes, that weakness is a wildcard...mid August, usually ridging wins with stuff this far south, even below normal heights could still mean ridging at this time of the season...in other words, climo favors W more than N for mid August. That being said, the trough seems a bit anomalously strong...

 

I can't go off with a hurricane forecast ywr, mostly because none of the modeling shows one, save for some stray runs from the FIM, CMC and NavGem models and also because there's nothing discrete of what to keep track of yet  . There have been many examples of weak TS or TDs entering the Bay of Campeche and then quickly developing...but they all got that look...that is, a healthy upper level support, banding and convection near the center. If it's just an amorphous blob of convection or shows signs of shear then forget it. I can see how this can become a hurricane, but I would like to see a few pieces where they should be first.

 

Things in the upper air will get rolling tomorrow when a new ULL pinches off the Atlantic TUTT and moves quickly W to WSW...that will help ventilate anything that could develop in the W Caribbean.

[Srain]

Raising the odds for possible mischief in the GoM (via NW Caribbean) to moderate. Reason is that models are still showing it to varying degrees (Euro has very weak depiction of something, so that's still concerning), and that land interaction appears to have lessened somewhat wrt Central America. Long wave trough weakening/splitting ridging in the N GoM adds complexity, and it looks there might be some troubles with upper air support if trough digs just enough to impart shear. Favored track would be NW Caribbean/Mexican Yucatan peninsula/and then W between latitudes 18N and 25N for now.

00Z looks a bit sheared as the Eastern trough drops S, but at least the mean is suggesting some potential, albeit weak.

 

 

[am19psu]

If that does develop, it might not be in a huge rush to move into Mexico judging by 700 mb and 500 mb heights, it is South of a weakness in the ridge.  Depends on where it comes off the Yucatan, the random GEFS ensemble member/FIM run with a turn to the North and then Northeast doesn't seem completely impossible, or, more likely, possibly two full days crossing the Gulf over some rather decent heat potential.  Could be situated under a weak anticyclone at 200 mb and 250 mb.  My natural optimism, if there was a coherent system approaching the coast neat Tampico, it'd be under very light upper flow while a forecast 35 knot flow over South Texas could be ventilating it.

 

You and Adam are more likely to be correct, but I can't help seeing the potential silver linings.

Lest you think I am always here just to beat you up, this was a pretty good post, Ed. Way better than posting a weenie model forecast and some fractional glass.

[Ed Lizard]

6Z GFS at hour 144, system would be on the road to at least being a named system.  Except for the latitude.  Below 20N and weakening within 12 hours, judging from four panels, land interaction as everything else looks favorable.  Move everything North a hundred miles or so, it'd have a shot.  Almost all of the spaghetti is also deep in the BoC and thus doesn't forecast significant development.

 

Unfortunate, the less reliably guidance is interesting, the more reliable guidance, not as much.

[Ed Lizard]

6Z GFS at hour 144, system would be on the road to at least being a named system.  Except for the latitude.  Below 20N and weakening within 12 hours, judging from four panels, land interaction as everything else looks favorable.  Move everything North a hundred miles or so, it'd have a shot.  Almost all of the spaghetti is also deep in the BoC and thus doesn't forecast significant development.

 

Unfortunate, the less reliably guidance is interesting, the more reliable guidance, not as much.

 

 

12Z GFS gives it that extra 2 degrees of latitude it needed coming off the Yucatan.  Mississippi at a TD or low end TS verbatim.

[gulfcane]

The GFS has no skill at forecasting tropical cyclone intensity. In fact, the NHC had no skill at predicting tropical cyclone intensity at days 2, 3, 4, and 5 in 2012. Best to go with climatology in this case which would favor a TS being able to strengthen into a hurricane in the GOM in mid August. 1006mb max intensity per GFS is unreasonable.

[28storms]

12Z CMC has a hurricane hitting south Texas. 

[Ed Lizard]

12Z GFS gives it that extra 2 degrees of latitude it needed coming off the Yucatan.  Mississippi at a TD or low end TS verbatim.

 

Verbatim is short hand for, yes, I know a somewhat coarse resolution global will not nail the intensity.  OTOH, the GFS was not without skill during the last TC, either in predicting development nor in predicting its weakening and demise.  I'm rather more concerned with the wide swing between the 6Z GFS, well supported by its ensembles, and the 12Z GFS

 

I'm rather curious what data (there aren't that many sites around the world that do 12Z balloon releases) made it into the 12Z, that neither the 6Z GFS nor 16 or 17 of 20 perturbed members didn't have to produce a rather wide swing.  I've seen it debunked many places that the off run GFS models are just run with the 6 hour forecasts of the previous run and no new data is initialized. 

 

Then again, maybe the Trinidad or Almirante sounding this morning really did make a difference.

 

Edit to Add

 

Quick look at NCEP NWATL 4 panels and PSU four panels may provide one clue why the GFS doesn't spin up a Cat 3 from a tropical depression in the less than 48 hours between the Yucatan and the North Central Gulf.  Potential system is inside a narrow corridor of >70% mean 700-500 mb RH, or dry air issues may counter favorable shear and OHC.

[am19psu]

The GFS has no skill at forecasting tropical cyclone intensity. In fact, the NHC had no skill at predicting tropical cyclone intensity at days 2, 3, 4, and 5 in 2012. Best to go with climatology in this case which would favor a TS being able to strengthen into a hurricane in the GOM in mid August. 1006mb max intensity per GFS is unreasonable.

Depends on what you mean by skill. Global models are pretty good at determining d(intensity)/dt, but not at getting the absolute intensity right. Ed's analysis is good.

And lol at calling the GFS depiction "unreasonable"

[am19psu]

Verbatim is short hand for, yes, I know a somewhat coarse resolution global will not nail the intensity.  OTOH, the GFS was not without skill during the last TC, either in predicting development nor in predicting its weakening and demise.  I'm rather more concerned with the wide swing between the 6Z GFS, well supported by its ensembles, and the 12Z GFS

 

I'm rather curious what data (there aren't that many sites around the world that do 12Z balloon releases) made it into the 12Z, that neither the 6Z GFS nor 16 or 17 of 20 perturbed members didn't have to produce a rather wide swing.  I've seen it debunked many places that the off run GFS models are just run with the 6 hour forecasts of the previous run and no new data is initialized. 

 

Then again, maybe the Trinidad or Almirante sounding this morning really did make a difference.

I'd guess it was more likely something way upstream over Asia affecting the H5 pattern over North America

[CoastalWx]

I agree with Adam. In fact, I think the globals are good at least hinting if the storm has the chance to become quite intense..or just perhaps a TD or TS. I don't know how you can throw models out and just go with climo straight up.

[am19psu]

Word, Scooter

[am19psu]

FWIW, 12z GEFS is similar to op