WTPZ41 KNHC 150232 RRA

TCDEP1



HURRICANE FERNANDA DISCUSSION NUMBER  13

NWS NATIONAL HURRICANE CENTER MIAMI FL       EP062017

800 PM PDT FRI JUL 14 2017



FERNANDA CONTINUES TO HAVE A VERY IMPRESSIVE APPEARANCE IN

SATELLITE IMAGERY, WITH A 10 N MI WIDE EYE WELL EMBEDDED IN A

SYMMETRIC CENTRAL DENSE OVERCAST.  THE HURRICANE ALSO HAS GOOD

OUTFLOW IN ALL DIRECTIONS AND OUTER CONVECTIVE BANDS IN ALL

QUADRANTS EXCEPT THE NORTHWEST.  SUBJECTIVE SATELLITE INTENSITY

ESTIMATES FROM TAFB AND SAB ARE NOW 127 KT, AND RECENT ESTIMATES

FROM THE CIMSS ADVANCED DVORAK TECHNIQUE ARE NOW 120 KT.  BASED

MAINLY ON THESE DATA, THE INITIAL INTENSITY IS INCREASED TO 125 KT.



THE INITIAL MOTION IS NOW 270/10.  THE TRACK FORECAST PHILOSOPHY

REMAINS THE SAME AS EARLIER, AS A MID-LEVEL SUBTROPICAL RIDGE TO

THE NORTH OF FERNANDA SHOULD INDUCE A GENERALLY WEST-NORTHWESTWARD

TRACK FOR THE NEXT SEVERAL DAYS.  SOME DECREASE IN FORWARD SPEED IS

LIKELY LATE IN THE FORECAST PERIOD WHEN THE TROPICAL CYCLONE NEARS A

WEAKNESS IN THE RIDGE.  THE NEW TRACK FORECAST IS ALMOST IDENTICAL

TO THE PREVIOUS FORECAST AND LIES NEAR THE VARIOUS CONSENSUS MODELS.



RECENT MICROWAVE IMAGERY INDICATES RAINBANDS ABOUT 30-40 N MI FROM

THE CENTER THAT ARE LIKELY THE START OF AN OUTER EYEWALL AND AN

EYEWALL REPLACEMENT CYCLE THAT WILL END THE CURRENT

INTENSIFICATION.  THE NEW INTENSITY FORECAST ALLOWS FOR 6-12 H MORE

STRENGTHENING BEFORE THIS HAPPENS. FROM 12-48 H, FERNANDA SHOULD

REMAIN IN A LOW SHEAR ENVIRONMENT OVER VERY WARM SEA SURFACE

TEMPERATURES. THE INTENSITY FORECAST CALLS FOR A SLOW WEAKENING

DURING THIS TIME AS A REFLECTION OF THE GUIDANCE.  HOWEVER,