WTPA43 PHFO 040254

TCDCP3



TROPICAL STORM IGNACIO DISCUSSION NUMBER  41

NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP122015

500 PM HST THU SEP 03 2015



DEEP CONVECTION AROUND THE CENTER OF IGNACIO HAS BEEN FADING ONCE

AGAIN...WITH SATELLITE IMAGERY SHOWING THE CYCLONE CONSISTING

MAINLY OF A SWIRL OF DEEP LAYERED CLOUDS. HOWEVER...THERE IS STILL A

WELL-DEFINED CENTER IDENTIFIABLE IN THE VISIBLE SATELLITE IMAGERY.

THE PHFO CURRENT INTENSITY ESTIMATE HAD COME DOWN FROM 4.0 IN THE

LAST ADVISORY TO 3.5...WHILE THE JTWC ESTIMATE HAD INCREASED FROM

3.5 TO 4.0. SAB KEPT THE INTENSITY CONSTANT IN THE LAST SIX HOURS

AND MAINTAIN A 3.5. BASED ON THIS...WILL MAINTAIN IGNACIO AS A 60 KT

TROPICAL STORM IN THIS ADVISORY.



IGNACIO HAS INDEED BEGUN TO MAKE IT/S ANTICIPATED NORTHWARD TURN.

THE INITIAL MOTION IS NOW 340/11. THE TRACK AND INTENSITY GUIDANCE

REMAIN TIGHTLY CLUSTERED. A MID-LEVEL TROUGH TO THE NORTHWEST OF THE

CYCLONE ALONG LONGITUDE 170W WILL PICK UP IGNACIO AND DRIVE IT

NORTHWARD TOWARD HIGHER LATITUDES AND GRADUALLY COLDER SEA SURFACE

TEMPERATURES. AFTER ABOUT 48 HOURS...IT WILL ENCOUNTER STRONGER

WESTERLIES WHICH WILL PROPEL IT QUICKLY EAST-NORTHEASTWARD ACROSS

THE CHILLY WATERS OF THE NORTH PACIFIC. SHEAR IS EXPECTED TO REMAIN

MODERATE FOR THE NEXT DAY OR SO...AND INCREASING BAROCLINIC

INFLUENCES MAY HELP TO SUSTAIN THE SYSTEM AS IT MERGES WITH A

FRONTAL BOUNDARY ON DAYS 2-3. EXTRATROPICAL TRANSITION IS EXPECTED

TO BEGIN BY DAY 3 WITH IGNACIO MOVING OVER SUB-20C SEA SURFACE

TEMPERATURES. IGNACIO WILL WIND UP AS A GALE LOW NEAR THE COAST OF

BRITISH COLUMBIA IN 5 DAYS.



FORECAST TRACK...INTENSITY...AND RADII FOR DAYS 3 THROUGH 5 WERE

COORDINATED WITH THE OCEAN PREDICTION CENTER IN WASHINGTON D.C.





FORECAST POSITIONS AND MAX WINDS



INIT  04/0300Z 30.4N 163.1W   60 KT  70 MPH

 12H  04/1200Z 32.0N 163.9W   60 KT  70 MPH

 24H  05/0000Z 34.6N 164.3W   60 KT  70 MPH

 36H  05/1200Z 37.4N 164.7W   60 KT  70 MPH

 48H  06/0000Z 40.4N 164.6W   55 KT  65 MPH...MERGING WITH FRONT

 72H  07/0000Z 46.5N 161.0W   50 KT  60 MPH...BECOMING EXTRATROPICAL

 96H  08/0000Z 51.5N 146.5W   45 KT  50 MPH...POST-TROP/EXTRATROP

120H  09/0000Z 54.9N 129.7W   40 KT  45 MPH...POST-TROP/EXTRATROP



$$

FORECASTER R BALLARD