069 
 WTPA41 PHFO 121449
 TCDCP1
 
 HURRICANE PALI DISCUSSION NUMBER  21
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP012016
 500 AM HST TUE JAN 12 2016
  
 AFTER EXHIBITING A RATHER WELL DEFINED EYE THROUGH THE EVENING...A
 RECENT BURST OF DEEP CONVECTION AROUND THE CENTER OF HURRICANE PALI
 HAS CAUSED THE EYE TO BECOME CLOUD FILLED...LIKELY DUE TO
 SOUTHWESTERLY VERTICAL WIND SHEAR OF AROUND 15 KT ACCORDING TO THE
 RECENT SHIPS AND CIMSS ANALYSES. DVORAK INTENSITY ESTIMATES FROM HFO
 AND JTWC CAME IN AT 4.5/77 KT...WHILE SAB AND CIMSS ADT REPORTED
 5.0/90 KT. BASED ON A BLEND OF THESE ESTIMATES...THE INTENSITY WILL
 BE RAISED CONSERVATIVELY TO 80 KT FOR THIS ADVISORY. ALSO...AN 0829
 UTC ASCAT PASS SHOWED SIMILAR WIND RADII VALUES TO THE PREVIOUS
 ADVISORY.
 
 PALI CONTINUES TO MOVE SOUTHWARD WITH AN INITIAL MOTION OF 170/06
 KT. THE HURRICANE REMAINS NEAR A LOW LEVEL TROUGH BETWEEN A
 PERSISTENT AREA OF WESTERLY WINDS NEAR AND SOUTH OF THE EQUATOR AND
 A DEEP RIDGE CENTERED ROUGHLY ALONG 20N. AN AREA OF HIGH PRESSURE
 EMBEDDED WITHIN THE RIDGE NEAR 175E IS BUILDING EASTWARD. THIS IS
 CAUSING THE ALREADY LOW LATITUDE HURRICANE TO MOVE SOUTHWARD...
 SOMETHING RARELY SEEN IN THE CENTRAL PACIFIC. AS PALI SLOWLY
 APPROACHES THE EQUATOR...DEEP EASTERLIES TO THE NORTH ARE EXPECTED
 TO INDUCE A WESTWARD MOTION BEYOND THURSDAY...THOUGH CONTINUED
 INTERACTION WITH THE LOW LATITUDE TROUGH MAY SLOW THE MOTION
 SOMEWHAT. OFFICIAL TRACK WAS ALTERED LITTLE FROM THE PREVIOUS
 ADVISORY AND REMAINS NEAR THE GFEX IN THE MIDDLE OF...BUT SLIGHTLY
 SLOWER THAN...THE RELIABLE TRACK GUIDANCE. WITH PALI MOVING CLOSER
 TO THE EQUATOR...UNCERTAINTY IN THE TRACK FORECAST BEYOND THE NEXT
 COUPLE OF DAYS IS HIGHER THAN NORMAL.
 
 THE INTENSITY FORECAST REMAINS CHALLENGING AS THE CYCLONE IS
 EXPECTED TO MOVE INTO EXTREMELY LOW LATITUDES NOT TYPICALLY
 OBSERVED. ALTHOUGH PALI WILL REMAIN OVER SEA SURFACE TEMPERATURES OF
 28 TO 29 C ALONG THE FORECAST TRACK...SHIPS INDICATES A MODEST
 INCREASE IN WIND SHEAR THAT COULD PRODUCE SOME WEAKENING DURING THE
 NEXT COUPLE OF DAYS. THE OFFICIAL FORECAST CLOSELY FOLLOWS THE SLOW
 WEAKENING TREND OF THE SHIPS AND LGEM THROUGH ABOUT 72 HOURS. AT
 THAT TIME AND BEYOND...SHIPS...LGEM...AND THE GFS SHOW A RE-
 INTENSIFICATION TREND...LIKELY DUE TO SHEAR RELAXING...WHILE THE
 GFDL...THE OUTLIER ON THE HIGH END OF THE GUIDANCE ENVELOPE...
 SUGGESTS WEAKENING. THE OFFICIAL INTENSITY FORECAST HAS BEEN HELD
 CONSTANT AT 72 HOURS AND BEYOND DUE TO HIGHER THAN NORMAL
 UNCERTAINTY AT THE EXTREMELY LOW LATITUDES ALONG THE FORECAST TRACK.
  
  
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  12/1500Z  6.8N 171.4W   80 KT  90 MPH
  12H  13/0000Z  5.9N 171.7W   75 KT  85 MPH
  24H  13/1200Z  4.8N 172.3W   75 KT  85 MPH
  36H  14/0000Z  3.9N 173.0W   70 KT  80 MPH
  48H  14/1200Z  3.1N 174.0W   65 KT  75 MPH
  72H  15/1200Z  2.5N 175.9W   60 KT  70 MPH
  96H  16/1200Z  2.5N 178.0W   60 KT  70 MPH
 120H  17/1200Z  2.5N 179.9W   60 KT  70 MPH
  
 $$
 FORECASTER WROE
 

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