WTNT44 KNHC 012045 RRA

TCDAT4



HURRICANE HERMINE DISCUSSION NUMBER  18

NWS NATIONAL HURRICANE CENTER MIAMI FL       AL092016

400 PM CDT THU SEP 01 2016



HERMINE WAS RECENTLY UPGRADED TO A HURRICANE BASED ON AN

SFMR-OBSERVED SURFACE WIND FROM AN AIR FORCE HURRICANE HUNTER

AIRCRAFT.  THE INITIAL INTENSITY IS SET AT 65 KT BASED ON THAT

OBSERVATION.  SATELLITE IMAGES SHOW THAT THE CLOUD PATTERN CONTINUES

TO GRADUALLY BECOME BETTER ORGANIZED WITH MORE DISTINCT CURVED BANDS

OF SHOWERS AND THUNDERSTORMS, ALTHOUGH THE SYSTEM CURRENTLY LACKS

CONCENTRATED INNER-CORE CONVECTION.  HERMINE HAS A LITTLE MORE TIME

TO STRENGTHEN, SO THE OFFICIAL FORECAST SHOWS A SLIGHT ADDITIONAL

INCREASE IN INTENSITY BEFORE LANDFALL.  THIS IS CONSISTENT WITH THE

LATEST LGEM GUIDANCE.  HERMINE IS FORECAST TO BECOME EXTRATROPICAL

AT 48 HOURS WHEN THE GLOBAL MODELS FORECAST IT TO BECOME EMBEDDED

WITHIN A FRONTAL ZONE.  LATER IN THE FORECAST PERIOD,

VERTICAL SHEAR DECREASES AND THE CYCLONE COULD BE SITUATED OVER

MARGINALLY WARM WATERS.  THEREFORE THERE IS THE POSSIBILITY OF THE

SYSTEM REGAINING SOME TROPICAL CHARACTERISTICS IN 4-5 DAYS, ALTHOUGH

THIS IS SPECULATIVE AT THIS TIME.



AIRCRAFT CENTER FIXES INDICATE THAT THE MOTION REMAINS 030/12 KT.

THE FLOW ON THE EASTERN SIDE OF A MID-LEVEL TROUGH OVER THE

SOUTHEASTERN UNITED STATES SHOULD CAUSE HERMINE TO MOVE

NORTH-NORTHEASTWARD TO NORTHEASTWARD WITH SOME INCREASE IN FORWARD

SPEED DURING THE NEXT DAY SO.  BY 48 HOURS, THE TRACK GUIDANCE

SHOWS THE SYSTEM SLOWING DOWN AS IT BEGINS TO INTERACT WITH A

MID-LEVEL CUTOFF VORTEX OVER THE EASTERN UNITED STATES.  IN 3 DAYS

OR SO, THE POST-TROPICAL CYCLONE MERGES WITH THE CUTOFF LOW AND A=