508 
 WTPA45 PHFO 160851
 TCDCP5
 
 TROPICAL STORM ANA DISCUSSION NUMBER  11
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   CP022014
 1100 PM HST WED OCT 15 2014
  
 ANA IS PRESENTING A DETERIORATED SATELLITE APPEARANCE THIS
 EVENING...AS IT CONTINUES TO ENCOUNTER MODERATE NORTH TO
 NORTHWESTERLY SHEAR. THE SHEAR ALSO INTRODUCES UNCERTAINTY WITH
 RESPECT TO THE CURRENT POSITION OF THE LOW LEVEL CENTER...BUT A 0402
 UTC SSMI/S PASS CONFIRMS WHAT EARLIER PASSES SUGGESTED...THAT THE
 CENTER REMAINS DISPLACED NORTHWEST FROM THE DEEPEST CONVECTION. 
 DVORAK INTENSITY ESTIMATES RANGED FROM 3.0/45 KT TO 3.5/55 KT...AND
 GIVEN THE RECENT SATELLITE TRENDS...THE INITIAL INTENSITY FOR THIS
 ADVISORY HAS BEEN LOWERED TO 50 KT. 
  
 THE INITIAL MOTION IS NEARLY DUE WEST AT 265/09 KT...TO THE SOUTH
 OF A DEEP LAYER RIDGE. LATEST GUIDANCE INDICATES THAT THE RIDGE
 PROVIDING THIS STEERING FLOW WILL REMAIN RELATIVELY UNCHANGED
 THROUGH EARLY THURSDAY...BEFORE SHIFTING SLIGHTLY TO THE EAST
 LATER THURSDAY INTO THE WEEKEND. THIS WILL PRODUCE A NORTHWESTWARD
 STEERING FLOW...WHICH IS EXPECTED TO TURN ANA TOWARD THE HAWAIIAN
 ISLANDS. THE LATEST TRACK GUIDANCE AIDS REMAIN TIGHTLY CLUSTERED...
 AND ARE CLOSE TO THE PREVIOUS FORECAST TRACK. THUS THE UPDATED
 FORECAST TRACK IS SIMILAR TO THE PREVIOUS...AFTER ACCOUNTING FOR THE
 WESTWARD MOTION SINCE THE PREVIOUS ADVISORY. THE TRACK TAKES THE
 CENTER OF ANA JUST SOUTH AND WEST OF THE BIG ISLAND FRIDAY NIGHT AND
 SATURDAY...THEN NEAR OAHU AND KAUAI OVER THE WEEKEND. FORWARD MOTION
 OF THE CYCLONE IS EXPECTED TO SLOW OVER THE WEEKEND AS STEERING
 CURRENTS WEAKEN DUE TO THE PASSAGE OF A LOW TO THE NORTH. THE NOAA 
 GULFSTREAM IV SAMPLED THE NEAR-STORM ENVIRONMENT EARLIER TODAY...AND 
 IS SLATED TO FLY AGAIN TOMORROW...PROVIDING VALUABLE ENVIRONMENTAL 
 DATA. 
  
 THE INTENSITY FORECAST REMAINS A CHALLENGE. ON ONE HAND...MORE THAN
 ADEQUATE SEA SURFACE TEMPERATURES AND AN EXPECTED DECREASE IN  
 VERTICAL WIND SHEAR WOULD SUPPORT INTENSIFICATION TO A HURRICANE OVER
 THE NEXT DAY OR TWO...IN LINE WITH HWRF AND GHM GUIDANCE. HOWEVER...
 SHIPS AND LGEM HAVE BEEN CONSISTENTLY LOWERING THE EXPECTED PEAK 
 INTENSITY OVER THE PAST 24 HOURS...AND ARE NOT FORECASTING ANA TO
 BECOME A HURRICANE. THE CURRENT DETERIORATION OF ANA IN SATELLITE
 IMAGERY LENDS CREDENCE TO THESE FORECASTS. THE INTENSITY FORECAST 
 FOR THIS PACKAGE IS A BLEND OF THE TWO...BUT DELAYS HURRICANE 
 INTENSITY UNTIL FRIDAY...WITH A PEAK INTENSITY OF 65 KT. IF ANA 
 FAILS TO REORGANIZE SOON...SUBSEQUENT INTENSITY FORECASTS MAY
 NEED TO BE NUDGED FURTHER DOWNWARD.
  
 IT IS IMPORTANT FOR PEOPLE IN THE MAIN HAWAIIAN ISLANDS NOT TO FOCUS
 TOO CLOSELY ON THE EXACT FORECAST TRACK OF ANA. WITH AN AVERAGE 48
 HOUR TRACK ERROR OF APPROXIMATELY 80 MILES...IT IS STILL TOO SOON TO
 SAY WITH MUCH CERTAINTY WHICH ISLANDS WILL BE MOST LIKELY TO 
 EXPERIENCE THE WORST WEATHER. EVERYONE SHOULD BE PREPARED FOR THE
 POSSIBILITY OF DIRECT IMPACTS FROM ANA. IT IS ALSO IMPORTANT TO KEEP
 IN MIND THAT SIGNIFICANT IMPACTS FROM TROPICAL CYCLONES CAN EXTEND
 WELL AWAY FROM THE CENTER.
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  16/0900Z 14.1N 149.3W   50 KT  60 MPH
  12H  16/1800Z 14.5N 150.7W   55 KT  65 MPH
  24H  17/0600Z 15.3N 152.6W   60 KT  70 MPH
  36H  17/1800Z 16.5N 154.6W   65 KT  75 MPH
  48H  18/0600Z 17.8N 156.0W   65 KT  75 MPH
  72H  19/0600Z 20.0N 157.6W   55 KT  65 MPH
  96H  20/0600Z 21.3N 159.2W   50 KT  60 MPH
 120H  21/0600Z 23.0N 161.5W   50 KT  60 MPH
  
 $$
 
 FORECASTER BIRCHARD