for a more recent update on hurricane paloma, CLICK HERE
Hurricane Paloma is tied for the 2nd strongest November Atlantic Hurricane. How does a hurricane get
140 mph winds in November? Same as any other time of year. How did it increase in intensity so quickly? It is not just the warm water, but more importantly the upper winds. The same thing that will eventually kill Paloma is the same thing that gave it muscle. There is a streak of very strong upper level winds generally from west to east along Cuba. That is great for enhancing the anti-cyclonic outflow aloft which in turn vents the storm and helps lower the pressure. You can see quite clearly on the IR Satellite that the outflow is developed much better on the northern half of the storm than the southern half. I had been thinking that this guy would move farther east than forecast and the storm has moved more east and the official forecast has been adjusted eastward. What giveth taketh away. As the storm moves into the flow of the upper winds, then those winds, instead of aiding in the upper flow, will instead rip the storm apart as it moves into the eastern third of Cuba. The front moving through the east coast of the US will not dig far enough south to really pick it up but will be significant enough to draw it more north.
So, this guy will get ripped to shreds over Cuba. The low level circulation will get disrupted by the mountains of eastern Cuba and the upper support will get ripped up by the westerly strong winds. As it emerges north of Cuba in the Bahamas, the ridge building into the eastern United States behind the front will start to drive the storm back west…BUT…the upper winds will remain very strong toward the east. So, Paloma will lose its head…the upper winds will separate the upper support from the low level circulation. The result is that, instead of a strong hurricane, you get a run of the mill surface low.
An interesting note about the storm surge. The NHC Forecast Discussion (below)
points out storm surges in excess of 20 feet possible for eastern Cuba. That is because the water piling up to the right of the storm will have nowhere to go but onshore. Now, it is possible that Paloma had stronger winds for a time prior to the current estimate of 140 mph. It has been raking the Cayman’s. But, my guess is that there is not much of a surge on those islands and so damage may not be as catastrophic as one might expect because its just wind, albeit Cat 4 hurricane winds, and not wind and surge. The reason why I suspect this is because that the Caymans are volcanic islands. They don’t have much of a shelf. The ocean floor drops almost straight down from the island coast. With the compressibility of water, the water simply goes around the island instead of up and over.
HURRICANE PALOMA DISCUSSION NUMBER 13
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL172008
1000 AM EST SAT NOV 08 2008
THE LAST FIX FROM THE AIR FORCE PLANE SUGGESTED THE MINIMUM PRESSURE HAS DROPPED TO LEAST 943 MB. IN ADDITION…PEAK FLIGHT LEVEL WINDS FROM THE AIR FORCE PLANE WERE 134 KT WITH SFMR READINGS OF 127 KT…THOUGH THE LATTER VALUE COULD BE A LITTLE INFLATED DUE TO SHOALING AROUND LITTLE CAYMAN/CAYMAN BRAC. SINCE THE PLANE DEPARTED…CLOUD-TOP TEMPERATURES HAVE WARMED A BIT…SO PERHAPS PALOMA’S INTENSITY HAS PEAKED. THE INITIAL INTENSITY REMAINS AT 120 KT…AND THE HURRICANE COULD HAVE BEEN A LITTLE STRONGER A FEW HOURS AGO. TWO MORE PLANES WILL BE IN THE AREA IN A FEW HOURS. RADAR FROM CAMAGUEY AND REPORTS FROM THE AIR FORCE RESERVE SUGGEST THAT PALOMA IS STARTING AN EYEWALL REPLACEMENT CYCLE WITH CONCENTRIC EYEWALLS NOTED. THIS STRUCTURE…COMBINED WITH SHEAR THAT IS LIKELY TO INCREASE TODAY…SUGGESTS THAT SLOW WEAKENING IS LIKELY. HOWEVER…PALOMA IS EXPECTED TO REMAIN A MAJOR HURRICANE UP THROUGH LANDFALL. THEREAFTER A RAPID WEAKENING SEEMS PROBABLE DUE TO THE EFFECTS OF LAND AND RATHER HIGH SHEAR FORECAST BY ALL GLOBAL MODELS. THIS WEAKENING SHOULD CONTINUE OVER THE ATLANTIC OCEAN AND PALOMA COULD START TO DISSIPATE IN A FEW DAYS. THE OFFICIAL FORECAST IS FAIRLY CLOSE TO THE SHIPS MODEL INITIALLY AND THEN IS A BLEND OF THE REST OF THE INTENSITY GUIDANCE AFTER LANDFALL IN CUBA. THE HURRICANE HAS TURNED A LITTLE MORE TO THE RIGHT AND APPEARS TO BE MOVING AT 060/8. NO CHANGE IN THE STEERING PATTERN IS EXPECTED IN THE SHORT-TERM…REQUIRING AN EASTWARD ADJUSTMENT OF THE NHC FORECAST. THEREAFTER…THE MODELS ARE IN MUCH BETTER AGREEMENT THAT PALOMA WILL DECOUPLE AND THE LOW-LEVEL CENTER WILL BE LEFT BEHIND OVER THE SOUTHWESTERN ATLANTIC OCEAN. LITTLE CHANGE IS MADE TO THE FORECAST IN THE LATER PERIODS AND THE OFFICIAL FORECAST ISN’T TOO FAR FROM THE MODEL CONSENSUS. IT IS WORTH EMPHASIZING THAT PALOMA WILL LIKELY BE QUITE WEAK AS IT BEGINS TO MOVE WESTWARD AT THE END OF THE PERIOD DUE TO STRONG WESTERLY SHEAR. EXCEPTIONALLY HIGH STORM SURGE VALUES OVER 20 FEET ARE POSSIBLE ALONG THE SOUTH COAST OF CUBA IN THE GULF OF GUACANAYABO DUE TO THE TRACK AND INTENSITY OF PALOMA. PALOMA IS TIED FOR THE SECOND STRONGEST ATLANTIC HURRICANE EVER NOTED IN NOVEMBER…THE STRONGEST BEING LENNY IN 1999.
FORECAST POSITIONS AND MAX WINDS
INITIAL 08/1500Z 19.9N 79.3W 120 KT
12HR VT 09/0000Z 20.4N 78.2W 110 KT
24HR VT 09/1200Z 21.0N 77.0W 85 KT…INLAND
36HR VT 10/0000Z 21.5N 76.4W 60 KT
48HR VT 10/1200Z 22.0N 76.0W 45 KT
72HR VT 11/1200Z 22.5N 75.8W 30 KT…DISSIPATING
96HR VT 12/1200Z 23.0N 76.3W 25 KT…REMNANT LOW
120HR VT 13/1200Z 23.0N 77.0W 20 KT…REMNANT LOW
$$ FORECASTER BLAKE