389 
 WTNT45 KNHC 150842
 TCDAT5
 HURRICANE OMAR DISCUSSION NUMBER   8
 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL152008
 500 AM EDT WED OCT 15 2008
 
 AN AIR FORCE HURRICANE HUNTER AIRCRAFT REPORTS THAT THERE HAS BEEN
 NO APPRECIABLE STRENGTHENING OF OMAR OVER THE PAST FEW HOURS.  AN
 ELLIPTICAL AND PARTIALLY OPEN EYE WAS OBSERVED BUT THE INNER CORE
 IS NOT YET WELL-DEFINED.  THE CENTRAL PRESSURE HAS NOT FALLEN AND
 MAXIMUM SFMR-OBSERVED SURFACE WIND SPEEDS HAVE BEEN NEAR 65
 KT...WHICH IS USED FOR THE ADVISORY INTENSITY.  SATELLITE IMAGES
 SHOW THAT OMAR CONTINUES TO GENERATE VERY DEEP CONVECTION WITH A
 LARGE AREA OF CLOUD TOPS COLDER THAN -80 DEG C.  UPPER-LEVEL
 OUTFLOW IS WELL-ESTABLISHED OVER THE EASTERN SEMICIRCLE AND
 RESTRICTED TO THE WEST...AS WESTERLY SHEAR CONTINUES TO IMPACT THE
 HURRICANE. HOWEVER...THE SHEAR IS NOT EXPECTED TO BE STRONG ENOUGH
 TO PREVENT STRENGTHENING.  THE OFFICIAL INTENSITY FORECAST IS THE
 SAME AS THE PREVIOUS ONE AND A LITTLE ABOVE THE MODEL CONSENSUS. 
 BY DAY 5...GLOBAL MODELS DEPICT THE CYCLONE INTERACTING WITH A
 STRONG BAROCLINIC ZONE OVER THE NORTH ATLANTIC SO THE OFFICIAL
 FORECAST SHOWS OMAR BECOMING EXTRATROPICAL BY THAT TIME.   
 
 INITIAL MOTION IS AROUND 050/6.  THERE HAS NOT BEEN MUCH CHANGE TO
 THE OFFICIAL FORECAST TRACK OR REASONING.  A MID-LEVEL TROUGH TO
 THE NORTH OF THE HURRICANE ALONG WITH A RIDGE TO THE EAST IS
 CREATING A SOUTHWESTERLY STEERING CURRENT AND OMAR IS EXPECTED TO
 CONTINUE NORTHEASTWARD WITH A GRADUAL INCREASE IN FORWARD SPEED. 
 THE FORWARD MOTION SLOWS A LITTLE AROUND DAY 3 AS THE TROUGH LIFTS
 OUT AHEAD OF OMAR.  THE SYSTEM SHOULD ACCELERATE AGAIN NEAR THE END
 OF THE PERIOD AS IT ENCOUNTERS THE MAIN BRANCH OF THE MID-LATITUDE
 WESTERLIES.  DYNAMICAL TRACK PREDICTION MODELS ARE TIGHTLY
 CLUSTERED...ESPECIALLY FOR THE FIRST 24 HOURS AND THE OFFICIAL
 FORECAST IS CLOSE TO THE MODEL CONSENSUS ALBEIT A LITTLE SLOWER. 
 THIS IS SLIGHTLY FASTER THAN THE PREVIOUS FORECAST...BUT MORE OR
 LESS ALONG THE SAME TRAJECTORY.
 
 ALTHOUGH THE OFFICIAL FORECAST KEEPS THE CENTER EAST OF PUERTO
 RICO...A DEVIATION TO THE LEFT OF THE CURRENT MOTION COULD REQUIRE
 CHANGING THE HURRICANE WATCH TO A HURRICANE WARNING FOR THAT
 ISLAND.
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      15/0900Z 14.6N  67.7W    65 KT
  12HR VT     15/1800Z 15.8N  66.5W    75 KT
  24HR VT     16/0600Z 18.0N  64.5W    85 KT
  36HR VT     16/1800Z 20.8N  62.2W    90 KT
  48HR VT     17/0600Z 23.8N  60.2W    90 KT
  72HR VT     18/0600Z 29.0N  57.0W    80 KT
  96HR VT     19/0600Z 35.0N  51.0W    70 KT
 120HR VT     20/0600Z 43.0N  37.0W    60 KT...EXTRATROPICAL
  
 $$
 FORECASTER PASCH