90W TCFA (升格01W) - 颱風討論

http://www.metoc.navy.mil/jtwc/products/wp0119prog.txt

WDPN32 PGTW 051500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 01W (ONE) WARNING
NR 004 RELOCATED//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION (TD) 01W (ONE), LOCATED APPROXIMATELY 267 NM
SOUTHEAST OF MAJURO, HAS TRACKED WEST-NORTHWESTWARD AT 06 KNOTS
(KTS) OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR)
SATELLITE IMAGERY SHOWS DEEP CONVECTION THAT DEVELOPED OVER THE LOW
LEVEL CIRCULATION CENTER OVER THE PAST 6 HOURS. THE INITIAL POSITION
IS BASED ON THE EIR IMAGERY WITH LOW CONFIDENCE. THE INITIAL
INTENSITY OF 25 KNOTS IS BASED ON A PGTW DVORAK CURRENT INTENSITY
ESTIMATE OF T1.0 (25 KTS). THE ENVIRONMENT IS MARGINALLY FAVORABLE
WITH LIGHT TO MODERATE (10-20 KT) VERTICAL WIND SHEAR (VWS), WEAK
RADIAL OUTFLOW, AND WARM (29-30 CELSIUS) SEA SURFACE TEMPERATURE.
THE CYCLONE IS TRACKING SLOWLY NORTHWESTWARD TOWARD A BREAK IN A
SUBTROPICAL RIDGE (STR) TO THE NORTH.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE. THE INITIAL POSITION WAS
RELOCATED ABOUT 180 NM TO THE SOUTHEAST OF THE PREVIOUS WARNING.
B. TD 01W WILL CONTINUE TRACKING SLOWLY NORTHWESTWARD TOWARD THE
BREAK IN THE STR UNTIL ABOUT TAU 36 WHEN THE STR WILL REBUILD TO THE
NORTH, ACCELERATING THE FORWARD SPEED AND TURNING TD 01W WEST-
NORTHWESTWARD. SLIGHTLY IMPROVED OUTFLOW WILL ENABLE SLIGHT
INTENSIFICATION TO 35 KNOTS BY TAU 48.
C. AFTER TAU 72, TD 01W WILL CONTINUE ON A WEST-NORTHWESTWARD
TRACK WITH LIMITED INTENSIFICATION UNDER MARGINALLY FAVORABLE
ENVIRONMENTAL CONDITIONS. NUMERICAL GUIDANCE IS IN POOR AGREEMENT,
PARTICULARLY IN THE EARLY STAGES WHILE TD 01W IS A MINIMAL TROPICAL
DEPRESSION, BUT ALL MEMBERS SHOW A WESTWARD TO WEST-NORTHWESTWARD
TRACK. THE RELOCATED POSITION BROUGHT THE INTERPOLATED NUMERICAL
GUIDANCE INTO BETTER AGREEMENT. THE SPREAD INCREASES RAPIDLY TO 100
NM BY TAU 24, BUT INCREASES MUCH MORE SLOWLY THEREAFTER. THE JTWC
FORECAST TRACK IS PLACED SLIGHTLY NORTH OF THE CONSENSUS, WITH
PERSISTENCE IN THE TRACK EARLY IN THE FORECAST CREATING THE
NORTHWARD DEVIATION WHICH CARRIES INTO THE LATER TAUS. CONFIDENCE IN
THE JTWC TRACK FORECAST IS LOW BASED PRIMARILY ON HIGH UNCERTAINTY
IN THE INITIAL POSITION.
4. JUSTIFICATION FOR RELOCATION: RELOCATED INITIAL POSITION OF TD
01W BASED ON 050924Z SCATTEROMETER DATA AND ANIMATED MULTISPECTRAL
SATELLITE IMAGERY PRIOR TO 050600Z.//
NNNN

http://www.metoc.navy.mil/jtwc/products/wp0119.gif

整理一下目前01W資訊:

1. 是MJO在西太形成輻合區所衍生出來的產物，附近系統有南半球08P的Peny和09P的MONA

2. 德法分析T1.0 風速為25KTS

3. 朝西北西前進，1月中旬有機會行進到菲東一帶間接影響冬夏系統的勢力分布

4. OHC和SSH偏低但SST仍有29~30度，有微弱的徑向流出，未來行經環境風切更為減弱，

老J看好形成2019年第2號颱風"蝴蝶"

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