WTPZ41 KNHC 310836 RRA

TCDEP1



HURRICANE NORMAN DISCUSSION NUMBER  13

NWS NATIONAL HURRICANE CENTER MIAMI FL       EP162018

200 AM PDT FRI AUG 31 2018



NORMAN APPEARS TO HAVE WEAKENED OVER THE PAST SEVERAL HOURS. CLOUD

TOPS AROUND THE EYE HAVE WARMED, AND THE EYE ITSELF HAS BECOME LESS

DISTINCT. SEVERAL RECENT MICROWAVE OVERPASSES SHOW LITTLE INDICATION

THAT AN EYEWALL REPLACEMENT CYCLE IS UNDERWAY, BUT IT IS POSSIBLE

THAT OUR ABILITY TO OBSERVE SUCH A CYCLE IS LIMITED BY THE

RESOLUTION OF THE AVAILABLE INSTRUMENTS. SATELLITE INTENSITY

ESTIMATES FROM ALL AGENCIES HAVE DECREASED AND SUPPORTED AT MOST AN

INTENSITY OF 125 KT AT 0600 UTC. GIVEN THE CONTINUED WARMING OF

CLOUD TOPS NEAR THE INNER CORE SINCE THAT TIME, THE INITIAL

INTENSITY HAS BEEN LOWERED TO 120 KT.



DUE TO THE LOWER INITIAL INTENSITY, THE INTENSITY FORECAST HAS ALSO

BEEN LOWERED SLIGHTLY, PARTICULARLY FOR THE FIRST 24 H. GRADUAL

WEAKENING IS EXPECTED THROUGH THE FORECAST PERIOD, THOUGH LARGER

SHORT-TERM FLUCTUATIONS IN INTENSITY DUE TO EYEWALL REPLACEMENT

CYCLES ARE POSSIBLE, IF NOT LIKELY, WHILE NORMAN REMAINS A

HURRICANE. BY THE END OF THE FORECAST PERIOD, A FASTER WEAKENING

RATE IS ANTICIPATED AS NORMAN IS FORECAST TO MOVE OVER COOLER SSTS

AND REACH A DRIER ENVIRONMENT. THE NHC FORECAST IS NEAR THE CENTER

OF THE INTENSITY GUIDANCE ENVELOPE AND NEAR THE INTENSITY CONSENSUS.



THE HURRICANE HAS CONTINUED TO MOVE WEST-SOUTHWESTWARD AT 8 KT.

ALMOST NO CHANGE HAS BEEN MADE TO THE TRACK FORECAST, WHICH REMAINS

CLOSE TO THE VARIOUS CONSENSUS AIDS. THE HURRICANE SHOULD TURN

WESTWARD, AND THEN WEST-NORTHWESTWARD, AS IT IS STEERED PRIMARILY BY

A DEEP-LAYER RIDGE TO THE NORTH FOR THE NEXT 5 DAYS. WITH THE