Monday, June 25, 2012

Debby sits and spins, and Cuba to Key West swim

Debby is nearly stationary sitting just south of Apalachicola FL. Mention of the Penny 
Palfrey swim after discussion of Debby.
The uncertainty in the forecast track is the only thing that remains unchanged.
This is always the problem in slow moving, weak systems. The cyclone is stuck in a 
col region between two large scale anti-cyclones, one over the Tropical Atlantic, and 
the other over the Southern Plains in weak steering flow.

The vorticity is stacked very nicely over the center of the storm with a robust ridge 
above 300 mb which is favorable for tropical system life cycles. The problem is that 
a mid level vort west of the storm last night and provided enough shear, with the trough 
to the north to move the deep convection east out over the Atlantic last night. Still Debby 
lies in an area of the Gulf of Mexico outside the warm waters of the loop current but the 
current is nearby.

Ecosystem viewer courtesy of NOAA Coastal Data Development Center 

The interesting item of the forecast today is that the GFS and the ECMWF have come into agreement with the EC now moving the storm over the western Atlantic. The images
below are the 96 hour forecast for the ECMWF and GFS respectively from the
Experimental forecast Tropical Cyclone Genesis Potential Fields courtesy of
Dr. Robert Hart Florida State University.

The obvious differences being the intensity in which the genesis model does not perform
well. The intensity i sup for grabs and depends on the eventual steering, progression, and
whether Debby taps into the Gulf Stream loop current to strengthen again. The only
certainty with the storm at this point is persistence in the slow movement for the next
several days. Debby may move across Florida and over the Atlantic by 96 hours, or just
drift across the Florida Panhandle and weaken. It is a waiting game. The official authority for hurricane forecasts, watches and warnings is the National
Weather Service, National Hurricane Center, and your local National Weather Service
Weather Forecast Office.
The bad news for Debby is as bad or worse for the Cuba to the Keys swim. Looks like
winds will remain near 20 knots through Wednesday and begin to shift SW and decrease
Wednesday night, which may hold the crossing for Sunluver until Wednesday afternoon.
10 meter winds, MSLP, and precipitation

The winds and seas diminish Thursday night and Friday but the earliest start for the swim
looks like Friday morning due to near 20 knots early Thursday, with seas finally dropping
below 3 to 5 feet late Thursday.
Wave hghts in meters, and wind flags in knots
We wait and hope.

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