Jump to content
  • Member Statistics

    17,609
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

Atlantic Tropical Action 2013


Recommended Posts

Omg.  Gettin' mild tingles here.

 

I still think tropical forecasting would be improved if the supercomputer running the CMC caught on fire and incinerated itself, but the UKMET text product:

 

EDIT: Note that this CANNOT be 97L due to the timing and location and obviously not 96L; it has to be the previously mentioned amorphous feature at 40W.

  NEW TROPICAL STORM FORECAST TO DEVELOP AFTER 108 HOURS                   FORECAST POSITION AT T+108 : 14.2N  61.8W  VERIFYING TIME     POSITION     STRENGTH        TENDENCY  --------------     --------     --------        -------- 00UTC 05.09.2013  14.2N  61.8W     WEAK 12UTC 05.09.2013  15.0N  64.5W   MODERATE  INTENSIFYING SLIGHTLY 00UTC 06.09.2013  15.6N  66.7W   MODERATE      LITTLE CHANGE 12UTC 06.09.2013  16.5N  69.4W   MODERATE  INTENSIFYING SLIGHTLY
Link to comment
Share on other sites

  • Replies 2.2k
  • Created
  • Last Reply

Barbados had several hours of Westerly winds, one hour over 10 knots, this afternoon.  Now a North wind in a thunderstorm.  I see a resemblance to a monsoonal trough in the imagery, and I wonder if this will take a bit longer to develop and develop farther West because it may be embedded in a monsoon trough like feature, and will take time to break away.  That actually favors enhanced risk for Florida, I'd think, later development.  And a connection to ITCZ/MT related moisture.  Speaking of which, CIMSS MIMIC TPW is getting better, but doesn't yet look ideal.  http://tropic.ssec.wisc.edu/real-time/mimic-tpw/natl/anim/latest72hrs.gif

 

Looking at FSU page GFS forecast shear, initially hostile shear seems to part like the Red Seas for 97L as it enters the Caribbean.  The old John Hope rules was more applicable in July and August, and also stated for a system 'that wasn't already a depression' passing the L. Antilles development would not occur before the Western Caribbean, so a small delay/more Western track seems like it might not be a bad thing.  I wasn't around for Gilbert (I was alive but in the West Pac), but I have seen satellite imagery, and that was the classic 'already a depression' example of a September storm going to town in the Eastern Caribbean.  Of course, it went to town even better in the Western Caribbean. 

 

850200shear20.png

Link to comment
Share on other sites

Hot off the press from the usually downplaying 57 dude:

"Quite a strong circulation evident on the MIMIC-TPW loop. Climatologically, such a strong wave might h ave a 30-40% chance of development in the Caribbean in 3-4 days. But I think development chances are higher than that. Probably after it passes west of the DR and is in the vicinity of PR. Could be a storm threatening the Gulf in 5 days."

He does have a typo.

Link to comment
Share on other sites

Oh goody... :rolleyes:

Wishcast, which could happen, 97L slowplays development (it is broad, and, IMHO, almost in a monsoon trough like feature), gets past 70W.  Nothing developing before that avoids the trough and avoids getting pulled North.  Starts developing past there, as trough has pushed offshore and heights rise over the East Coast, then gets pulled up into Florida, maybe sort of like Charley, by a disturbance both the GFS and Euro show riding down the ridge in 6 days.

 

Or, the Euro is actually very likeable, except it doesn't start developing 97L once past 70W.  Note below Euro map with childish scrawls on it.

post-138-0-35953800-1377993941_thumb.gif

Link to comment
Share on other sites

Convection is blossoming over 97L tonight...

 

acv676.gif

 

According to NHC, nothing to see here. 

 

SURFACE OBSERVATIONS AND DROPSONDE DATA FROM A NOAA GULFSTREAM

AIRCRAFT SHOW A BROAD AREA OF LOW PRESSURE ASSOCIATED WITH A

TROPICAL WAVE IS CENTERED ABOUT 350 MILES EAST OF THE LESSER

ANTILLES. CLOUDINESS AND SHOWERS ASSOCIATED WITH THIS SYSTEM

REMAIN DISORGANIZED...AND THERE IS NO EVIDENCE OF A WELL-DEFINED

SURFACE WIND CIRCULATION. ENVIRONMENTAL CONDITIONS ARE NOT

CURRENTLY FAVORABLE FOR DEVELOPMENT...BUT COULD BECOME A LITTLE

MORE CONDUCIVE FOR SOME DEVELOPMENT WHEN THE WAVE REACHES THE

WESTERN CARIBBEAN SEA IN 4 OR 5 DAYS. THIS SYSTEM HAS A LOW

CHANCE...10 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE

NEXT 48 HOURS...AND A LOW CHANCE...20 PERCENT...OF BECOMING A

TROPICAL CYCLONE DURING THE NEXT 5 DAYS. SHOWER ACTIVITY AND

LOCALLY GUSTY WINDS ASSOCIATED WITH THIS SYSTEM ARE EXPECTED TO

SPREAD OVER THE LESSER ANTILLES DURING THE NEXT DAY OR TWO.

Link to comment
Share on other sites

Hot off the press from the usually downplaying 57 dude:

"Quite a strong circulation evident on the MIMIC-TPW loop. Climatologically, such a strong wave might h ave a 30-40% chance of development in the Caribbean in 3-4 days. But I think development chances are higher than that. Probably after it passes west of the DR and is in the vicinity of PR. Could be a storm threatening the Gulf in 5 days."

He does have a typo.

 

Hawt.  Thx for sharing.

 

beggars can't be choosers

 

Bingo.  I'll take even this right now.

Link to comment
Share on other sites

Mid-level relative humidity values are forecast to increase over the following days as Invest 97L tracks westward. Haven't seen that too much this season, though it makes sense in this case.

 

700-500 MB RH     52    55    56    55    55    58    60    61    61    63    61    63    63

 

Wind shear should continue to lower:

SHEAR (KT)        14    11     5     5    11     2     8     2     7     6     5     7    12

 

SSTs are a go:

SST ©         28.6  28.6  28.7  28.8  28.9  29.0  29.1  29.2  29.2  29.1  29.1  29.1  29.3

 

Vertical instability is average:

TH_E DEV ©      10    10    10    11    11    11    11    10    11    10    12    12    13

 

Liking the chances for this one if it doesn't develop quickly and get pulled north over the Greater Antilles.
Link to comment
Share on other sites

Please, just once let the SHIPS/LGEM be right...

 

00z SHIPS enviorement would favor something pretty hawt with the BAMM track. 

*   ATLANTIC SHIPS INTENSITY FORECAST       *
                    * GOES AVAILABLE,       OHC AVAILABLE       *
                    *      INVEST  AL972013  09/01/13  00 UTC   *

TIME (HR)          0     6    12    18    24    36    48    60    72    84    96   108   120
V (KT) NO LAND    25    25    26    28    29    34    42    51    57    63    69    74    77
V (KT) LAND       25    25    26    28    29    34    42    51    57    63    69    74    77
V (KT) LGE mod    25    25    25    26    27    30    36    43    53    64    77    88    95
Link to comment
Share on other sites

If 97L doesn't develop into a hurricane, it looks like a decent chance to set the record to have the latest first hurricane in the Atlantic on record.

Euro not excited about it either.  I'd like the path to the Bahamas, if it developed.

 

Convection has been maintaining, and it even looks like it is developing outflow to the South, pushing some cirrus Westward, but with neither the GFS or Euro developing it, there must be something missing.  On the positive side, it takes the GFDL an entire 48 hours to lose it.  And outer grid tracks a disturbance to Cuba.  FIM-9 looks a bit like the GFS, with the trailing wave eventually starting to interact with 97L, and the trailing wave looking better than 97L as it gets turned away to the Northwest, but not quite developing through a week..

 

 

 

EDIT TO ADD

 

Looking at PSU Euro 4 panel, the weak system in the Bahamas is also the wave behind 97L.

 

 

 

700thetae21.png

post-138-0-59875200-1378020584_thumb.gif

post-138-0-25227500-1378021537_thumb.png

Link to comment
Share on other sites

You mean for the modern/recon/satellite era-- i.e., from the mid-20 century.  The best-track record is actually 08 Oct, in 1905.

That may be true, but I discount a lot of numerical records from that era, like latest hurricane to form.  It may be true that one didn't form until Oct 8th, but we don't know for certain. 

Link to comment
Share on other sites

That may be true, but I discount a lot of numerical records from that era, like latest hurricane to form.  It may be true that one didn't form until Oct 8th, but we don't know for certain. 

 

Of course not, which is why I qualified it by saying it was pre-modern.  It is understood by all of us that the pre-modern record is imperfect.  But given that it exists, and that we refer to it and use this for statistical analysis, it is not correct to say that 11 Sep is the latest a season's first hurricane has ever formed in the NATL.

Link to comment
Share on other sites

Globals are still awfully meh with that wave. Kind of a red flag.

 

We just can't win this year.  :D  I forgot what it's like to see a NATL tropical cyclone just pop up and bomb out.  Everything is such a struggle these days-- not just this year but the last few.  Even the rare moments of hawtness seem to happen suddenly and are very short-lived and localized-- like Karl 2010's short-lived bomb-out in the Bay of Campeche or Ernie 2012's very short-lived pre-Yucatan intensification or Sandy 2012's very short-lived pre-Cuba intensification.  Even these cool moments are quick and come after long periods of struggle.

Link to comment
Share on other sites

Of course not, which is why I qualified it by saying it was pre-modern.  It is understood by all of us that the pre-modern record is imperfect.  But given that it exists, and that we refer to it and use this for statistical analysis, it is not correct to say that 11 Sep is the latest a season's first hurricane has ever formed in the NATL.

People 100 years from now will be lucky enough to have 150 years of satellite records and 7 day models that are as accurate as 24 hour ones.  It both a bummer and exciting that we are so close to the beginning of understanding tropical storms.  I like the mystery still.

Link to comment
Share on other sites

We just can't win this year.   :D  I forgot what it's like to see a NATL tropical cyclone just pop up and bomb out.  Everything is such a struggle these days-- not just this year but the last few.  Even the rare moments of hawtness seem to happen suddenly and are very short-lived and localized-- like Karl 2010's short-lived bomb-out in the Bay of Campeche or Ernie 2012's very short-lived pre-Yucatan intensification or Sandy 2012's very short-lived pre-Cuba intensification.  Even these cool moments are quick and come after long periods of struggle.

 

Well maybe it gets its act together, but there is a little SW shear and some sort of conv trough with shwrs/tstms ahead of it. Not really what I would like to see, but maybe it moves away and it organizes down the road. Not really looking "hawt" right now.

 

The season is just entering climo peak. My gut says it may be a late one so maybe homebrew season gets to be interesting October and beyond.

Link to comment
Share on other sites

Well maybe it gets its act together, but there is a little SW shear and some sort of conv trough with shwrs/tstms ahead of it. Not really what I would like to see, but maybe it moves away and it organizes down the road. Not really looking "hawt" right now.

Ha ha ha, definitely nawt hawt. Lolz. :D

 

The season is just entering climo peak. My gut says it may be a late one so maybe homebrew season gets to be interesting October and beyond.

Yep-- that's what I'm counting on-- some deep-tropical, W-basin, late-season hatwness. I'm totally ignoring Africa now-- do not give a crap what comes out of there. Hoping for an African wave to make it across and become hawt this year is like watching a kitten trying to cross a ten-lane highway-- just painful. Any Cape Verde cyclone that's going to make it across and have a significant impact on North America needs to form by around 15 Sep-- then it's basically game over-- and the long-range models are already showing that timeframe with basically nada.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Guest
This topic is now closed to further replies.
  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...