JTWC 10/31 00Z PROGNOSTIC REASONING
WDPN31 PGTW 310300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 22W (GONI)
WARNING NR 013//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUPER TYPHOON 22W (GONI), LOCATED APPROXIMATELY 454 NM
EAST OF MANILA, PHILIPPINES, HAS TRACKED WEST-SOUTHWESTWARD
AT 12 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY (MSI) DEPICTS A COMPACT, POWERFUL SYSTEM
WITH A WELL DEFINED 7 NM EYE. WHILE STILL COMPACT IN NATURE
IT HAS INCREASED IN SIZE OVER THE PAST 6 HOURS. THE INITIAL
POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE WELL
DEFINED EYE FEATURE IN THE MSI LOOP. THE INITIAL INTENSITY
OF 160 KTS IS FURTHER PLACED WITH HIGH CONFIDENCE AND IS
HEDGED SLIGHTLY ABOVE MULTI-AGENCY DVORAK CURRENT INTENSITY
ESTIMATES OF T7.5 (155 KTS, PGTW AND RJTD) BASED ON RECENT
ADVANCED DVORAK TECHNIQUE CURRENT INTENSITY ESTIMATES OF T7.6
(158 KTS). ANALYSIS OF THE EYE WALL STRUCTURES IN SEVERAL
MICROWAVE IMAGES SUGGESTS THAT AN EYE WALL REPLACEMENT CYCLE
(ERC) IS IMMINENT. DESPITE THIS, THE OVERALL CONVECTIVE
STRUCTURE, CLOUD TOP AND EYE TEMPERATURES ARE IN AGREEMENT
THAT A WEAKENING PHASE, TYPICAL OF ERC, HAS NOT YET COMMENCED.
STY GONI HAS CONTINUED TO TRACK ALONG THE SOUTHERN PERIPHERY
OF THE SUBTROPICAL RIDGE (STR) POSITIONED OVER SOUTHERN CHINA
AND THROUGH AN OVERALL FAVORABLE ENVIRONMENT WITH VERY WARM
(30 DEG CELSIUS) WATERS, LOW (10-15 KNOTS) VWS AND ROBUST
RADIAL OUTFLOW. POLEWARD OUTFLOW REMAINS ESPECIALLY STRONG.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. STY GONI WILL CONTINUE TO TRACK GENERALLY SOUTHWESTWARD
TO SOUTH-SOUTHWESTWARD OVER THE NEXT 24 HOURS. THE ENVIRONMENT
WILL REMAIN OVERALL FAVORABLE FOR DEVELOPMENT, HOWEVER A
GRADUAL WEAKENING IS FORECAST DURING THIS TIME DUE TO THE ERC
AND, DECREASING POLEWARD OUTFLOW ASSOCIATED WITH THE ONGOING
REPOSITIONING OF THE STEERING RIDGE, AND A SMALL INCREASE IN
VWS (15-20 KTS). STY GONI WILL THEN MAKE LANDFALL ALONG THE
COAST OF LUZON, EAST OF MANILA, BETWEEN TAU 24 AND TAU 36 AS A
SIGNIFICANT TROPICAL CYCLONE. AS THE SYSTEM TRANSITS ACROSS
LUZON AND INTO THE SOUTH CHINA SEA, IT WILL FURTHER WEAKEN DUE
TO TERRAIN INTERACTION TO AN INTENSITY OF 75 KTS BY TAU 48. AS
THE SYSTEM TRACKS OVER THE SOUTH CHINA SEA BETWEEN TAU 48 AND
TAU 72, IT WILL STEADILY WEAKEN TO AN INTENSITY OF 60 KTS DUE
TO CONTINUED MODERATE TO HIGH (20-25 KTS) VWS. NUMERICAL MODEL
GUIDANCE IS IN GOOD AGREEMENT DURING THIS INITIAL PORTION OF
THE JTWC FORECAST TRACK, WITH A TOTAL SPREAD IN ACROSS TRACK
MODEL SOLUTIONS OF 150 NM AT TAU 72. SPECIFICALLY THE NAVGEM
TRACK LIES NORTHWARD OF THE OTHER JTWC MULTI-MODEL CONSENSUS
MEMBERS. AS SUCH, THIS INITIAL PORTION OF THE JTWC FORECAST IS
PLACED SLIGHTLY SOUTH OF THE JTWC MULTI-MODEL CONSENSUS WITH
OVERALL HIGH CONFIDENCE.
C. IN THE EXTENDED FORECAST, THE SYSTEM WILL TRACK WESTWARD
ALONG THE SOUTHERN PERIPHERY OF THE DEEP-LAYER STR POSITIONED
TO THE NORTH THROUGH THE END OF THE FORECAST, AND MAKE A SECOND
LANDFALL ALONG THE CENTRAL VIETNAM COAST BETWEEN TAU 96 AND TAU
120. THE SYSTEM WILL CONTINUE TO WEAKEN UNDER THE INFLUENCE OF
MODERATE VWS AND CONTINUED ENTRAINMENT OF DRY MID-LEVEL AIR.
NUMERICAL MODEL TRACK GUIDANCE HAS CONVERGED SINCE THE LAST
FORECAST WITH ONLY NAVGEM PREDICTING A NORTHWESTWARD TRACK
TOWARDS HAINAN. THE REMAINING MEMBERS OF THE JTWC MULTI-MODEL
CONSENSUS AGREE WITH A WESTWARD TRACK DURING THIS TIME. AS SUCH
THE JTWC FORECAST TRACK FOR THE REMAINDER OF THE FORECAST IS
PLACED SOUTH OF THE MULTI-MODEL CONSENSUS WITH OVERALL FAIR
CONFIDENCE TO OFFSET THE NORTHWESTWARD BIAS CONTRIBUTED BY THE
NAVGEM TRACK.//
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簡單翻譯一下6小時總結與分析的部分
綠色部分為現況強度分析與理由
颱風眼周圍被緊密與強悍的雲團包裹著，在過去6小時颱風的大小仍在持續擴張。
中心位置與強度具有高度信心使用眼型來分析，
160kts的分析結果是基於多種人工預報的德沃夏克分析法（PGTW與RJTD皆分析T7.5），
以及進階的德沃夏克分析法得到T7.6（158kts）的CI值。
黃色部分為進入眼牆置換循環的狀況說明
根據眼牆結構在微波掃描的結果顯示，眼牆置換循環即將開始。
除此之外，目前的對流、雲頂溫度與眼溫也支持颱風進入減弱週期，
典型的眼牆置換循環階段還沒正式開始。
人工的DT分析得到T7.5，加上ADT分析得到T7.6，
因此就給160kts了，意外簡潔的理由。
眼牆置換00Z還沒正式開始，然後差不多06Z就完成了...