WTPA34 PHFO 021445
TCPCP4

BULLETIN
HURRICANE JIMENA ADVISORY NUMBER 28
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP132015
500 AM HST WED SEP 02 2015

…HURRICANE JIMENA WEAKENING SLIGHTLY FAR EAST-SOUTHEAST OF THE
MAIN HAWAIIAN ISLANDS…

SUMMARY OF 500 AM HST…1500 UTC…INFORMATION
———————————————-
LOCATION…17.7N 142.8W
ABOUT 815 MI…1315 KM ESE OF HILO HAWAII
ABOUT 1015 MI…1630 KM ESE OF HONOLULU HAWAII
MAXIMUM SUSTAINED WINDS…110 MPH…175 KM/H
PRESENT MOVEMENT…WNW OR 295 DEGREES AT 8 MPH…13 KM/H
MINIMUM CENTRAL PRESSURE…961 MB…28.38 INCHES

WATCHES AND WARNINGS
——————–
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

DISCUSSION AND 48-HOUR OUTLOOK
——————————
AT 500 AM HST…1500 UTC…THE CENTER OF HURRICANE JIMENA WAS
LOCATED NEAR LATITUDE 17.7 NORTH…LONGITUDE 142.8 WEST. JIMENA IS
MOVING TOWARD THE WEST-NORTHWEST NEAR 8 MPH…13 KM/H. JIMENA IS
FORECAST TO GRADUALLY TURN TOWARD THE NORTHWEST AT A SLOWER FORWARD
SPEED LATER TODAY AND TONIGHT. THIS SLOW NORTHWESTWARD MOTION WILL
LIKELY CONTINUE THROUGH THURSDAY NIGHT.

MAXIMUM SUSTAINED WINDS ARE NEAR 110 MPH…175 KM/H…WITH HIGHER
GUSTS. GRADUAL WEAKENING IS FORECAST THROUGH THURSDAY NIGHT.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 60 MILES…95 KM…FROM
THE CENTER…AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 185
MILES…295 KM.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 961 MB…28.38 INCHES.

HAZARDS AFFECTING LAND
———————-
LARGE SWELLS FROM HURRICANE JIMENA WILL PRODUCE HAZARDOUS SURF
ALONG EAST FACING SHORES OF THE MAIN HAWAIIAN ISLANDS. THE SURF
WILL BUILD TODAY…AND CONTINUE THROUGH THIS WEEKEND.

NEXT ADVISORY
————-
NEXT COMPLETE ADVISORY…1100 AM HST.

$$
FORECASTER HOUSTON



WTPA44 PHFO 021501
TCDCP4

HURRICANE JIMENA DISCUSSION NUMBER 28
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP132015
500 AM HST WED SEP 02 2015

THE EYE OF JIMENA CONTINUED TO BECOME LESS DISTINCT IN INFRARED
SATELLITE IMAGERY TONIGHT. IN FACT…AS OF THIS ADVISORY ISSUANCE
THE EYE IS NO LONGER DISCERNIBLE. THIS MAY BE DUE IN PART TO AN
APPARENT EARLIER EYEWALL REPLACEMENT CYCLE…WHICH HAD BEEN NOTED IN
MICROWAVE IMAGERY ON TUESDAY THAT WERE PROVIDED VIA THE NRL/FNMOC
WEB SITES. ALSO…THE MOST RECENT ESTIMATES OF ENVIRONMENTAL
VERTICAL WIND SHEAR WERE 6 KT FROM 285 DEGREES ACCORDING TO UW-CIMSS
AND 11 KT FROM 315 DEGREES BASED ON THE SHIPS ANALYSIS.
THEREFORE…THIS SHEAR MAY BE DOING SOME HARM TO THE INNER CORE OF
JIMENA. NOTE THAT THE GENERAL APPEARANCE OF THE OUTFLOW PATTERN OF
JIMENA CONTINUES TO LOOK REASONABLY HEALTHY. THE LATEST ADT AND THE
SUBJECTIVE DVORAK CURRENT INTENSITY ESTIMATES FROM PHFO AND SAB WERE
5.0/90 KT. THE ESTIMATE FROM JTWC WAS 5.5/102 KT. THEREFORE…WE
WILL DROP THE INITIAL INTENSITY TO 95 KT FOR THIS ADVISORY. NOTE
THAT A PARTIAL 0722Z ASCAT PASS OVER MOST OF THE WESTERN SEMICIRCLE
OF JIMENA WAS USED TO ADJUST THE INITIAL WIND RADII FOR THIS
ADVISORY…ESPECIALLY IN THE SOUTHWEST QUADRANT.

THE INITIAL MOTION HAS SLOWED SLIGHTLY…AND IT IS NOW TOWARD THE
WEST-NORTHWEST OR 295/07 KT. JIMENA CONTINUES TO BE STEERED BY A
WEAKENING NORTHWEST TO SOUTHEAST ORIENTED MID LEVEL RIDGE LOCATED
NORTHEAST AND EAST OF THE SYSTEM. THE GLOBAL FORECAST MODELS
INDICATE THIS STEERING MECHANISM WILL CONTINUE TO WEAKEN DURING THE
NEXT 24 HOURS…CAUSING JIMENA TO GRADUALLY TURN NORTHWESTWARD AND
DECREASE ITS FORWARD MOTION. THIS SLOW NORTHWESTWARD MOTION WILL
LIKELY CONTINUE THROUGH DAY 2. BEYOND 48 HOURS…THE GLOBAL MODEL
OUTPUT SHOWS AN UPPER LEVEL TROUGH DIGGING TOWARD THE SOUTHEAST TO
THE NORTH OF JIMENA. THAT SYSTEM IS EXPECTED TO CAUSE JIMENA TO TURN
TOWARD THE NORTH-NORTHWEST AT A SLIGHTLY FASTER FORWARD SPEED DURING
THE 3-4 DAY TIME PERIOD. THE 5 DAY POSITION NOW INDICATES A TURN
TOWARD THE NORTHWEST AGAIN. THE CURRENT FORECAST TRACK IS VERY CLOSE
TO THE PREVIOUS…WITH SOME SLIGHT NUDGING TO THE RIGHT BASED ON THE
LATEST TVCN AND GFEX CONSENSUS GUIDANCE.

SEA SURFACE TEMPERATURES /SST/ REMAIN NEAR 28C ALONG MOST OF THE
FORECAST TRACK. OF NOTE IN THE RECENT CIRA ANALYSES OF OCEAN HEAT
CONTENT /OHC/ IS THAT JIMENA APPEARS TO BE TRAVELING IN A LOCAL
MINIMUM OF THIS PARAMETER ALONG ITS FORECAST TRACK. THESE LOWER
VALUES OF OHC MAY BE DUE TO PREVIOUS HURRICANES THAT HAVE RECENTLY
TRAVERSED THIS REGION OF THE PACIFIC OCEAN. THE LATEST SHIPS
GUIDANCE SHOWS MODEST WEST-SOUTHWEST TO SOUTHWEST WIND SHEAR. THESE
ENVIRONMENTAL CONDITIONS ARE EXPECTED TO PRODUCE SLOW WEAKENING
DURING THE NEXT 48 HOURS. AFTER 72 HOURS…COOLER SST VALUES AND
INCREASING SHEAR ARE EXPECTED TO PRODUCE MORE RAPID WEAKENING. THE
LATEST INTENSITY FORECAST SHOWS SLIGHTLY FASTER WEAKENING THAN OUR
PREVIOUS FORECAST…AND CLOSELY FOLLOWS THE ICON…IVCN AND SHIPS.

FORECAST POSITIONS AND MAX WINDS

INIT 02/1500Z 17.7N 142.8W 95 KT 110 MPH
12H 03/0000Z 18.1N 143.2W 90 KT 105 MPH
24H 03/1200Z 18.6N 143.7W 85 KT 100 MPH
36H 04/0000Z 19.2N 144.1W 80 KT 90 MPH
48H 04/1200Z 19.9N 144.4W 75 KT 85 MPH
72H 05/1200Z 21.6N 144.8W 70 KT 80 MPH
96H 06/1200Z 24.0N 145.5W 65 KT 75 MPH
120H 07/1200Z 26.0N 147.0W 55 KT 65 MPH

$$
FORECASTER HOUSTON