Atlantic Tropical Action 2013

[Ed Lizard]

Rob,

 

Solid reasoning...I think you have learned from the "bust" with Independent Wx. a few seasons ago. The SSTA- / heights-based rolling methodology seems to be a solid basis for forecasting the August-September geo-potential heights, especially given the ENSO signal. However, I would have also included the PDO as a factor into your forecast, along with the April-May 200-mb pattern. Perhaps using a bit of Sam's MQI indicators as well as the SIOD could have added more depth and support to your ideas.

 

A more active than usual season with Florida as the preferred target, this could be an interesting season.  It also seems to match other people's ideas, which would seem to indicate people using different methods and arriving at similar analogs might be on to something.

 

 

GFS looks less impressive on ex-Barbara than earlier run.

[Ground Scouring]

A more active than usual season with Florida as the preferred target, this could be an interesting season.  It also seems to match other people's ideas, which would seem to indicate people using different methods and arriving at similar analogs might be on to something.

 

 

GFS looks less impressive on ex-Barbara than earlier run.

There are actually several areas of vorticity, of which only the one near Veracruz is ex-Barbara. And the GFS has handled the convective evolution of the Yucatán mess (surface trough / developing low?) rather poorly. It no longer develops a low over the Yucatán and delays U.S. landfall until day 6 or later. The model has been highly inconsistent in both track and timing, while the ECMWF still develops a low overnight over the Yucatán and shows FL landfall in five days.

[Srain]

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1124 AM EDT SUN JUN 02 2013

VALID 12Z WED JUN 05 2013 - 12Z SUN JUN 09 2013

 

...HEAVY RAINFALL FOR SOUTH FLORIDA AND INCREASING UNCERTAINTY
ABOUT TROPICAL DEVELOPMENT...

 

THE BIGGEST CHANGE IN GLOBAL NUMERICAL GUIDANCE IN THE LAST 24
HOURS IS A LARGE UPTICK IN THE NUMBER OF MODEL ENSEMBLE
MEMBERS--BOTH GEFS AND ECENS--THAT DEVELOP A TROPICAL CYCLONE FROM
THE PRIMORDIAL TROPICAL SOUP CURRENTLY ENVELOPING THE REGION FROM
THE BAY OF CAMPECHE TO THE CARIBBEAN SEA JUST EAST OF THE YUCATAN
PENINSULA. HERETOFORE, THE MODELS--WITH THE EXCEPTION OF THE GEM
GLOBAL--INDICATED THAT THE SHORTWAVE TROUGH CROSSING THE EASTERN
UNITED STATES AT THE MEDIUM RANGE WOULD HAVE SUFFICIENT AMPLITUDE
TO SHEAR THE BULK OF MOISTURE AND ENERGY OVER THE EASTERN GULF OF
MEXICO NORTHEASTWARD ALONG THE REACTIVATED FRONTAL ZONE OFF THE
EAST COAST. NOW, MANY ENSEMBLE MEMBERS SHOW LESS AMPLITUDE WITH
THE NORTHERN SHORTWAVE, HENCE, LESS SHEAR OVER THE EASTERN GULF,
HENCE, MORE OPPORTUNITY FOR TROPICAL CYCLONE DEVELOPMENT. WILL BE
COORDINATING WITH THE NATIONAL HURRICANE CENTER AT 1700Z THIS
AFTERNOON TO DISCUSS THE SITUATION, WITH ANY CHANGES TO THE MANUAL
FRONTAL PROGS SENT THIS MORNING TO BE REFLECTED IN THE AFTERNOON
HEMISPHERIC ISSUANCE.

 

CHOSE THE 00Z/02 ECENS MEAN AS A SYNOPTIC GUIDE TODAY, AS IT
REFLECTED THE "BAGGINESS" TO THE MASS FIELDS OVER THE GULF OF
MEXICO AND EASTERN STATES APPROPRIATE TO A LARGE SPREAD IN
SOLUTIONS, AND SHOWED REASONABLE CONTINUITY OVER THE NORTHEAST
PACIFIC AND WESTERN NORTH AMERICA. IN GENERAL, HEAVY RAINFALL IS
STILL ANTICIPATED ACROSS SOUTH FLORIDA--DESPITE THE EVENTUAL
OUTCOME OF THE GULF "SOUP," WITH THE POSSIBILITY OF SOAKING RAINS
OVER ANY PORTION OF THE EASTERN UNITED STATES NEAR THE TRACK OF
ANY ORGANIZED LOW EMERGING FROM THE GULF OF MEXICO. THE CENTRAL
STATES LOOKS WET WITH A MEAN LONGWAVE TROUGH IN PLACE THERE. THE
FAR WEST LOOKS HOT AND DUSTY UNDER A MEAN RIDGE.

CISCO

[Ground Scouring]

When will Drs. Gray/Klotzbach's June 2013 update be released? I would assume tomorrow or June 4...right?

[Ground Scouring]

The 12Z ECWMF is much slower with the TC and apparently shows a much stronger LF near Tampa in about four and a half days. The 96-hr. frame shows a deeper (1006-mb) TC in the east-central Gulf than on the 00Z run, and the 120-hr. frame depicts a 1002-mb TS hitting GA. I am guessing that the intervening LF near Tampa would have been about 1003 mb or slightly lower...or at least as strong as in the previous run. Can anyone confirm? What is most marked is the better co-location between the mid-level and low-level lows, meaning reduced shear over the cyclone while approaching FL.

[HurricaneJosh]

Would love to see a 65-kt appetizer hittin' the W coast of FL this week. Early-season yummies!!1!

[WxFreak11]

Would love to see a 65-kt appetizer hittin' the W coast of FL this week. Early-season yummies!!1!

Absolutely! The beginning of June it's perfectly acceptable but by September..we will have no tolerance for such things!

[U_Thant]

East gulf systems of 50kt+ rarely fail to produce at least a couple decent (high end EF-1, maybe low end EF-2) TORs over the central FL peninsula.

[Superstorm93]

I bet Josh is tingling all over in anticipation of an asymmetric 40 knot storm.

Btw we have invest 91L

Sent from Tapatalk

[HurricaneJosh]

Absolutely! The beginning of June it's perfectly acceptable but by September..we will have no tolerance for such things!

Bingo.  

 

I bet Josh is tingling all over in anticipation of an asymmetric 40 knot storm.

Btw we have invest 91L

Well, I am a little tingly, actually. Like Pluffmud suggests, it's fun given the time of year-- something to track.

[HurricaneJosh]

No changes to da Lemon, as of 2 am EDT. Not blown away by the modeling for this one.

Adam? Comment, pls.

[am19psu]

Models seem to be vacillating between sheared and non-sheared solutions based on the strength and depth of the H5 shortwave late in the week. Latest trends are for a deeper shortwave, which will keep the system sheared, but it's obviously not set in stone 5 days out. There are some hints of decent deepening right before landfall, probably aided by the right entrance of the jet streak associated with the H5 shortwave. My best guess says 40 kts into the Big Bend, but it's pretty uncertain right now given the variance in the modeled H5 pattern. One other thing to keep in mind, SSTs are pretty bleh across the NE Gulf right now, so there may not be much thermodynamic help for the system as it approaches land.

[HurricaneJosh]

Models seem to be vacillating between sheared and non-sheared solutions based on the strength and depth of the H5 shortwave late in the week. Latest trends are for a deeper shortwave, which will keep the system sheared, but it's obviously not set in stone 5 days out. There are some hints of decent deepening right before landfall, probably aided by the right entrance of the jet streak associated with the H5 shortwave. My best guess says 40 kts into the Big Bend, but it's pretty uncertain right now given the variance in the modeled H5 pattern. One other thing to keep in mind, SSTs are pretty bleh across the NE Gulf right now, so there may not be much thermodynamic help for the system as it approaches land.

K, thx. Nice havin' such cleverness on hand like this.

[wxmeddler]

Recon Scheduled for tomorrow afternoon:

I. ATLANTIC REQUIREMENTS
1. SUSPECT AREA---GULF OF MEXICO
FLIGHT ONE -- TEAL 70
A. 04/1900Z
B. AFXXX 01XXA INVEST
C. 04/1730Z
D. 24.0N 88.5W
E. 04/1845Z TO 04/2300Z
F. SFC TO 10,000 FT.

[Ground Scouring]

CSU (Drs. Gray/Klotzbach) has just released its June update...apparently, nothing has changed. The authors, however, almost seem to expect the no-majors cycle to end this year. On the other hand, if their forecast proves wrong, I would expect complacency to increase dramatically if we see another, unanticipated year without a major landfall in the U.S.:

 

 

Other than the two very active landfall years of 2004 and 2005, the United States has not experienced as many major hurricanes as would be expected given this active cycle.

“The United States has been especially fortunate in experiencing no major hurricane landfalls since 2005,” Gray said. “Prior to the past seven years, there had not been a seven-year period on record since 1851 with no major hurricane landfalls in the United States. These conditions should not be expected to continue.”

 

http://www.news.colostate.edu/Release/6880

[Roger Smith]

Readers of this thread are invited to enter the seasonal contest (separate thread on this forum page) and please note, today (June 3rd) is the last day for entries without penalties. I see that quite a few have already entered, but if you enter today, be sure to read post #1 to get an overview of the contest rules.

[DopplerWx]

12z GFS looks like a rainmaker for the tampa area and then looks to send it out to sea just offshore the east coast.  looks like it gets sheared and never has a chance to get its act together.

[phil882]

Again this setup looks somewhat similar to the evolution of Debby last year, where we saw the initial vortex develop out of a gyre like disturbance and then merge with a frontal boundary as the storm made landfall over Florida. Like Adam, I'm not seeing anything more substancial than a 40-50 knot disturbance that remains highly sheared during its entire lifecycle. 

 

Take a look at these two Dynamic tropopause loops (plotted are pressure on dynamic tropopause surface (2PVU) with low-level relative vorticity contoured).

 

Debby (2012):

 

http://www.atmos.albany.edu/student/ppapin/mapdisco/20120914/dt_pres/debby.html

 

Invest 91L:

 

http://www.atmos.albany.edu/student/kgriffin/maps/dtpres/dtpres_namer_loop.html

 

The # 1 threat with these type of disturbances in the heavy rainfall that they can generate over a very large area, and this system should be no exception. 

[hurricaneman]

Tornadoes have to be a threat too, if its anything like Debby last year that threat is there

[icebreaker5221]

Not sure how much CAPE there'll be, but there could be a notable tornado threat for FL (also like Debby) this Thu should any low-topped supercells form. 

 

[bluewave]

CSU (Drs. Gray/Klotzbach) has just released its June update...apparently, nothing has changed. The authors, however, almost seem to expect the no-majors cycle to end this year. On the other hand, if their forecast proves wrong, I would expect complacency to increase dramatically if we see another, unanticipated year without a major landfall in the U.S.:

 

The interesting thing is that we didn't need any major landfalls  in recent years for several very high impact to historic events.

 

Hurricane Ike .....2008

Hurricane Irene...2011 

Hurricane Isaac...2012

Hurricane Sandy..2012

 

[Shawn]

Tornadoes have to be a threat too, if its anything like Debby last year that threat is there

 

If the system comes in like the last CMC run showed (through GA), SC will have tors to worry about too.  I think Beryl (remnants) dropped 2 F3+ in my home town alone with a similar track in 1994

[wxtrackercody]

Got a 30% tangerine. 

 

A WEAK LOW PRESSURE AREA LOCATED OVER THE SOUTH-CENTRAL GULF OF
MEXICO CONTINUES TO PRODUCE DISORGANIZED SHOWERS AND THUNDERSTORMS.
SATELLITE IMAGERY AND SURFACE OBSERVATIONS SUGGEST THAT THE
CIRCULATION OF THE LOW HAS BECOME SLIGHTLY BETTER DEFINED TODAY.
ADDITIONAL GRADUAL DEVELOPMENT IS POSSIBLE DURING THE NEXT COUPLE
OF DAYS DESPITE MARGINALLY FAVORABLE ENVIRONMENTAL CONDITIONS. THIS
SYSTEM HAS A MEDIUM CHANCE...30 PERCENT...OF BECOMING A TROPICAL OR
SUBTROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT DRIFTS GENERALLY
NORTHWARD. REGARDLESS OF DEVELOPMENT...LOCALLY HEAVY RAINS ARE
LIKELY IN ASSOCIATION WITH THE LOW OVER PORTIONS OF THE YUCATAN
PENINSULA...CENTRAL AND WESTERN CUBA...AS WELL AS THE FLORIDA KEYS
AND THE FLORIDA PENINSULA DURING THE NEXT SEVERAL DAYS.

[DopplerWx]

18z GFS still takes a tampa track, I agree with others that it will probably be too sheared for anything of tropical merit, but a slight change in track will be important to those in fl/ga in regards to a tornado threat.  Can't compain about having something to watch this early in the season.

[Srain]

Got a 30% tangerine. 

 

A WEAK LOW PRESSURE AREA LOCATED OVER THE SOUTH-CENTRAL GULF OF

MEXICO CONTINUES TO PRODUCE DISORGANIZED SHOWERS AND THUNDERSTORMS.

SATELLITE IMAGERY AND SURFACE OBSERVATIONS SUGGEST THAT THE

CIRCULATION OF THE LOW HAS BECOME SLIGHTLY BETTER DEFINED TODAY.

ADDITIONAL GRADUAL DEVELOPMENT IS POSSIBLE DURING THE NEXT COUPLE

OF DAYS DESPITE MARGINALLY FAVORABLE ENVIRONMENTAL CONDITIONS. THIS

SYSTEM HAS A MEDIUM CHANCE...30 PERCENT...OF BECOMING A TROPICAL OR

SUBTROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT DRIFTS GENERALLY

NORTHWARD. REGARDLESS OF DEVELOPMENT...LOCALLY HEAVY RAINS ARE

LIKELY IN ASSOCIATION WITH THE LOW OVER PORTIONS OF THE YUCATAN

PENINSULA...CENTRAL AND WESTERN CUBA...AS WELL AS THE FLORIDA KEYS

AND THE FLORIDA PENINSULA DURING THE NEXT SEVERAL DAYS.

[Josh]It's called a mandarin. K thnx[/Josh]

[HurricaneJosh]

[Josh]It's called a mandarin. K thnx[/Josh]

Kinda excitin' that we might be havin' Andrea soon. I notice the SHIPS brings it up to ~45 kt-- not amazin', but better than 24 hr ago.

[free_man]

Can you provide some reasoning behind your 'prediction'?

I upped to 13/8.5/6 or something like that.

[HurricaneJosh]

I know Adam's awake. But the bowl's empty.

[am19psu]

I know Adam's awake. But the bowl's empty.

The only difference in today's model runs is more shear right before landfall. Both the GFS and Euro show the system elongating and almost jumping the FL Peninsula Friday morning. 

[HurricaneJosh]

The only difference in today's model runs is more shear right before landfall. Both the GFS and Euro show the system elongating and almost jumping the FL Peninsula Friday morning.

Blah. K, thx.