Tropical Storm SOUDELOR Advisory Thu Jul 30

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 13W (THIRTEEN) WARNING
NR 02//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TROPICAL STORM (TS) 13W (THIRTEEN), LOCATED APPROXIMATELY 564 NM NORTHEAST
OF CHUUK, FSM, HAS TRACKED WESTWARD AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED
ENHANCED INFRARED (EIR) SATELLITE IMAGERY (MSI) SHOWS A CONSOLIDATING SYSTEM WITH
FORMATIVE BANDS WRAPPING INTO A LOW LEVEL CIRCULATION CENTER THAT IS OBSCURED BY
A CENTRAL DENSE OVERCAST FEATURE. THE INITIAL POSITION IS BASED ON THE EIR LOOP
AND ON A 301046Z AMSU-B MICROWAVE PASS WITH POOR CONFIDENCE. THE INITIAL
INTENSITY OF 35 KNOTS IS BASED ON AN OVERALL ASSESSMENT OF DVORAK
ESTIMATES FROM PGTW, KNES, AND RJTD. UPPER-LEVEL ANALYSIS INDICATES A
MARGINALLY-FAVORABLE ENVIRONMENT WITH LOW TO MODERATE VERTICAL WIND
SHEAR (VWS) OFFSET BY GOOD POLEWARD OUTFLOW, ENHANCED BY A TUTT CELL
TO THE NORTH-NORTHWEST. ALONG-TRACK SSTS ABOVE 28 CELSIUS AND HIGH
OCEAN HEAT CONTENT ARE ALSO CONDUCIVE FOR FURTHER DEVELOPMENT. THE
CYCLONE IS CURRENTLY TRACKING ALONG THE SOUTHERN PERIPHERY OF A
DEEP-LAYERED SUBTROPICAL RIDGE (STR) TO THE NORTH.
3. FORECAST REASONING.
   A.  THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY
FROM THE PREVIOUS PROGNOSTIC REASONING MESSAGE.
   B. TS 13W IS FORECAST TO TRACK WESTWARD TO WEST-NORTHWESTWARD
THROUGHOUT THE FORECAST UNDER THE INFLUENCE OF THE STR. WITH
ENVIRONMENTAL CONDITIONS EXPECTED TO BE CONDUCIVE FOR DEVELOPMENT,
THE SYSTEM WILL REACH 100 KNOTS BY TAU 72.
   C. IN THE EXTENDED TAUS, UPPER LEVEL CONDITIONS WILL BECOME
INCREASINGLY FAVORABLE WITH LOW VWS AND EXCELLENT DIVERGENT OUTFLOW.
BY THE END OF THE FORECAST, TS 13W WILL REACH 125 KNOTS. NUMERIC
MODEL GUIDANCE IS IN GOOD AGREEMENT. HOWEVER, DUE TO THE DEVELOPMENTAL
STAGE OF THE SYSTEM, THERE IS, FOR NOW, LOW CONFIDENCE IN THE JTWC TRACK FORECAST.//
STAGE OF THE SYSTEM, THERE IS, FOR NOW, LOW CONFIDENCE IN THE JTWC TRACK FORECAST.//