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Sciencerocks wrote:I'd go 110knts. Eye isn't nearly defined enough and there's no where near enough of a complete ring of deep enough convection to justify 125knts. It is also starting to enter colder water so I am thinking it will start weakening soon.
cycloneye wrote:Hurricane2022, it reached 130kt-135kt, but now is downhill. AFTER PEAKING AT OR SLIGHTLY ABOVE 130 KNOTS
ABOUT EIGHT HOURS AGOWDXS31 PGTW 182100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 13S (DJOUNGOU) WARNING
NR 007//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 21.6S 81.0E
INITIAL INTENSITY: 120 KTS
GEOGRAPHIC REFERENCE: 1000 NM SOUTH-SOUTHEAST OF DIEGO GARCIA
MOVEMENT PAST 6 HOURS: SOUTHEASTWARD AT 29 KTS
SIGNIFICANT WAVE HEIGHT: 56 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
TROPICAL CYCLONE (TC) 13S (DJOUNGOU) IS NOW RAPIDLY DETERIORATING
AFTER PEAKING ABOUT EIGHT HOURS AGO. REANALYSIS OF THE ADVANCED
DVORAK TECHNIQUE (ADT) RAW DATA OUTPUTS WHICH REACHED AS HIGH AS T6.8,
THE SYSTEM APPEARS TO HAVE PEAKED BETWEEN 180900Z AND 181000Z,
BETWEEN 130 AND 135 KNOTS. SINCE THAT TIME, THE EYE HAS QUICKLY
FILLED IN AND IS NO LONGER APPARENT IN THE ANIMATED ENHANCED
INFRARED (EIR) IMAGERY. THE CLOUD TOPS REMAIN FAIRLY COLD IN THE
EIR AND AN 181628Z AMSU-B 89GHZ MICROWAVE IMAGE REVEALED A WELL-
DEFINED UPPER-LEVEL MICROWAVE EYE FEATURE. THE IMPACT OF NORTHWESTERLY
SHEAR WAS ALREADY EVIDENT IN MICROWAVE IMAGERY FROM 181304Z, WHICH
SHOWED A PRONOUNCED TILT BETWEEN THE 36GHZ AND 89GHZ EYE FEATURES. THE
INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE BASED ON THE TIGHT
GROUPING OF THE AGENCY FIXES, WHICH WERE PLACED USING THE LAST COUPLE
OF FRAMES WITH AN EVIDENT EYE FEATURE, AND EXTRAPOLATION OF THE AMSU-B
MICROWAVE EYE FEATURE NOTED ABOVE. THE INITIAL INTENSITY IS ASSESSED
WITH MEDIUM CONFIDENCE, BASED ON AN AVERAGE OF THE SUBJECTIVE AND
OBJECTIVE FIXES NOTED BELOW. ANALYSIS SHOWS THAT THE SYSTEM HAS MOVED
INTO AN ENVIRONMENT WHICH HAS VERY RAPIDLY SHIFTED FROM FAVORABLE TO
HIGHLY UNFAVORABLE, WITH HIGH VWS BEING THE PRIMARY NEGATIVE FACTOR.
SSTS REMAIN WARM AND UPPER-LEVEL OUTFLOW CONTINUES TO BE EXTREMELY
STRONG POLEWARD, INTO THE BASE OF A 130 KNOT JET MAX TO THE SOUTHEAST.
THE SYSTEM IS RACING SOUTHEASTWARD AT ALMOST 30 KNOTS IN THE TIGHT
GRADIENT FLOW BETWEEN A STR TO THE EAST AND A MAJOR SHORTWAVE TROUGH
TO THE WEST.
INITIAL WIND RADII BASIS: PERSISTENCE
CURRENT STEERING MECHANISM: TIGHT GRADIENT BETWEEN A STRONG STR
CENTERED OVER WESTERN AUSTRALIA AND A DEEP, MAJOR SHORTWAVE TROUGH
TO THE WEST.
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T6.5 - 127 KTS
KNES: T6.5 - 127 KTS
DEMS: T6.5 - 127 KTS
FMEE: T6.5 - 127 KTS
FIMP: T5.5 - 102 KTS
CIMSS SATCON: 125 KTS AT 181307Z
CIMSS ADT: 124 KTS AT 181800Z
CIMSS AIDT: 116 KTS AT 181800Z
CIMSS DPRINT: 117 KTS AT 181800Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: HIGHLY UNFAVORABLE
VWS: 30+ KTS
SST: 28-29 CELSIUS
OUTFLOW: STRONG POLEWARD
OTHER FACTORS: VERY DRY AIR BEGINNING TO WRAP UP THE WEST AND
NORTH OF THE LLCC.
ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: MEDIUM
INITIAL WIND RADII: LOW
3. FORECAST REASONING.
SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST TRACK FROM THE PREVIOUS WARNING, OTHER THAN A
TRUNCATION TO 48 HOURS. HOWEVER, THE FINAL PHASE TRANSITION HAS
BEEN CHANGED TO EXTRATROPICAL WITH THIS FORECAST.
FORECAST DISCUSSION: AFTER PEAKING AT OR SLIGHTLY ABOVE 130 KNOTS
ABOUT EIGHT HOURS AGO, TC 13S HAS STARTED TO RAPIDLY WEAKEN AS IT
SUCCUMBS TO PERSISTENT AND INCREASING NORTHWESTERLY SHEAR AND
BEGINS TO FEEL THE EFFECTS OF SIGNIFICANT INTRUSIONS OF DRY AIR.
THE STEERING INFLUENCE IS QUITE STRAIGHT FORWARD, AND WILL DRIVE
THE SYSTEM TOWARDS THE SOUTHEAST AT A STEADY 30 KNOTS FOR THE NEXT
24 TO 36 HOURS. A SLIGHT SLOW DOWN AND SHIFT TO AN EASTWARD TRACK
IS EXPECTED BY THE END OF THE FORECAST AS THE STEERING LEVEL SHIFTS
LOWER IN THE ATMOSPHERE, WHERE THE STEERING GRADIENT WILL BE
WEAKER. WITH THE SHEAR HAVING NOW SUCCESSFULLY PENETRATED TO
THE INNER CORE OF THE SYSTEM, IT WILL NOT BE LONG BEFORE THE VORTEX
IS COMPLETELY TORN ASUNDER. IN FACT THE DECAPITATION INDEX (DCAP)
MODEL SUGGESTS THIS PROCESS WILL BE COMPLETE WITHIN THE NEXT 12 TO
24 HOURS. AT THE SAME TIME, BOTH THE HAFS-A AND HWRF MODEL CROSS-
SECTIONS SHOW THE PROCESS VERY WELL, WITH ALL THAT REMAINS OF THE LOW-
LEVEL VORTEX DRIVING SOUTHEASTWARD BY TAU 36, COMPLETELY SMOTHERED BY
A DEEP LAYER OF VERY DRY AIR EXTENDING FROM 800MB ALL THE WAY UP TO
300MB. THE SYSTEM WILL BEGIN SUBTROPICAL TRANSITION (STT) SHORTLY BUT
THIS PHASE OF ITS LIFE WILL BE SHORT-LIVED, AND IT WILL NEVER ACTUALLY
COMPLETE STT. INSTEAD, THE SYSTEM QUICKLY SHIFTS TO AN EXTRATROPICAL
TRANSITION (ETT) AS IT MOVES INTO THE LEFT ENTRANCE REGION OF A 150
KNOT JET MAX AND EMBEDS ALONG A TIGHT THERMAL GRADIENT AND DEVELOPS
FRONTAL CHARACTERISTICS. ETT WILL BE COMPLETE NO LATER THAN TAU 48 AND
COULD POTENTIALLY WRAP UP 12 HOURS EARLIER.
MODEL DISCUSSION: TRACK GUIDANCE IS IN VERY TIGHT AGREEMENT, WITH
MINIMAL CROSS AND ALONG-TRACK SPREAD THROUGH THE SHORT DURATION OF
THE FORECAST PERIOD. THE JTWC FORECAST LIES CLOSE TO THE CONSENSUS
MEAN WITH HIGH CONFIDENCE. INTENSITY GUIDANCE IS ALSO IN GOOD
AGREEMENT, WITH ALL OF THE GUIDANCE SHOWING A SHARP AND RAPID
WEAKENING THROUGH THE DURATION OF THE FORECAST. THE JTWC FORECAST
LIES ON THE HIGHER END OF THE ENVELOPE WITH MEDIUM CONFIDENCE.
But what is the final estimate? 130 or 135 kts? 
cycloneye wrote:Hurricane2022, good question you asked. What was the real peak?
Now going down in a hurry.
13S DJOUNGOU 240219 0000 23.1S 83.3E SHEM 105 954
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