236
WTPA42 PHFO 100245
TCDCP2
HURRICANE DORA DISCUSSION NUMBER 39
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP052023
500 PM HST WED AUG 09 2023
DORA HAS BEGUN TO SLOWLY GAIN LATITUDE THIS AFTERNOON, AS FORECAST,
BUT HAS STRENGTHENED ONCE AGAIN WITHIN A LOW-SHEAR AND MARGINALLY
WARM SEA SURFACE TEMPERATURE ENVIRONMENT. SATELLITE PRESENTATION
HAS IMPROVED FROM LATE THIS MORNING, WITH A CLEARLY DEFINED 8 NM
WIDE EYE AND A SYMMETRICAL CENTRAL STRUCTURE. THE CENTRAL DENSE
OVERCAST FEATURE AROUND THE CORE IS LESS THAN 100 NM WIDE, GIVING
DORA AN INCREASINGLY ANNULAR APPEARANCE. THIS INTENSE BUT COMPACT
SYSTEM IS ONLY ABOUT 240 NM WIDE FROM NORTH TO SOUTH, INCLUDING ALL
BANDING FEATURES. ALL THREE FIX AGENCIES DERIVED SUBJECTIVE DVORAK
INTENSITY ESTIMATES OF 6.5, CORRESPONDING TO 127 KT. LATEST UW-CIMSS
ADT IS 122 KT. GIVEN THESE DERIVED INTENSITY VALUES, DORA IS GIVEN
AN INITIAL INTENSITY OF 125 KT FOR THIS ADVISORY, KEEPING HER AS A
SOLID CATEGORY 4 TROPICAL CYCLONE.
INITIAL MOTION WITH THIS ADVISORY IS 275/19 KT, UNCHANGED FROM THE
LAST TWO ADVISORIES. LIKE BEFORE, TRACK GUIDANCE REMAINS REMARKABLY
TIGHT THROUGH TAU 72, WITH SPREAD ONLY BECOMING SIGNIFICANT AT TAU
96 AND BEYOND, LONG AFTER THIS SYSTEM HAS PASSED OUT OF THE BASIN
INTO THE WESTERN NORTH PACIFIC. THE LARGER SYNOPTIC ENVIRONMENT
AROUND DORA REMAINS UNCHANGED. STRONG RIDGING NORTH OF DORA, AND
THE WESTWARD MIGRATION OF THIS RIDGING, ACCOUNTS FOR THIS SYSTEM'S
PROLONGED WESTWARD MOVEMENT. HOWEVER, THE SLOW AND RECENT INCREASE
IN LATITUDE INDICATES THAT DORA IS REACHING THE SOUTHWEST FLANK OF
THIS RIDGING. DORA IS FORECAST TO CONTINUE GAINING LATITUDE AND
ASSUME A NORTHWEST MOTION THURSDAY AND FRIDAY. THE FORECAST TRACK,
CLOSELY FOLLOWING THE PREVIOUS TRACK AND TVCN MODEL CONSENSUS,
CONTINUES TO BECOME MORE NORTHERLY AFTER DORA PASSES WEST OF THE
DATE LINE.
WARM WATER, WITH TEMPERATURES OF 28 DEGREES C OR ABOVE, LIES ALONG
THE ENTIRE FORECAST TRACK AND SHEAR WILL REMAIN LESS THAN 20 KT
THROUGH TAU 60. WITH 00Z ECMWF SHIPS SHOWING ALMOST NO DORA
INTENSITY DROP THROUGH TAU 24, THIS ADVISORY WILL ONLY SLOWLY
WEAKEN THIS SYSTEM THROUGH TAU 36, WITH MORE PRONOUNCED WEAKENING
INTRODUCED AFTERWARDS AS DORA GAINS LATITUDE AND SHEAR INCREASES.
THE 00Z GFS SHIPS SHOWS A SIMILAR SLOW WEAKENING TREND THROUGH TAU
24, WITH MORE RAPID WEAKENING AFTERWARDS. AS BEFORE, BOTH SHIPS
VERSIONS KEEP DORA STRONGER AT ALL TAU THAN MOST INTENSITY MODEL
GUIDANCE. HOWEVER, GIVEN THAT DORA INSISTS ON STRENGTHENING WITHIN
THE ENVIRONMENT IT IS IN, FORECASTING A SLOWER WEAKENING TREND, AT
LEAST INITIALLY, SEEMS REASONABLE. DORA WILL EVENTUALLY WEAKEN TO A
POST-TROPICAL/REMNANT LOW, BUT AFTER TAU 120.
FORECAST POSITIONS AND MAX WINDS
INIT 10/0300Z 11.8N 167.9W 125 KT 145 MPH
12H 10/1200Z 12.0N 170.8W 120 KT 140 MPH
24H 11/0000Z 13.1N 174.4W 115 KT 130 MPH
36H 11/1200Z 14.4N 177.9W 115 KT 130 MPH
48H 12/0000Z 15.3N 179.1E 110 KT 125 MPH
60H 12/1200Z 16.1N 176.2E 105 KT 120 MPH
72H 13/0000Z 16.8N 173.2E 95 KT 110 MPH
96H 14/0000Z 18.1N 168.0E 70 KT 80 MPH
120H 15/0000Z 20.7N 164.2E 50 KT 60 MPH
FORECASTER POWELL
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page