WDPN32 PGTW 250900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 10W (FRANCISCO) 
WARNING NR 013//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 26.5N 122.6E
   INITIAL INTENSITY: 30 KTS
   GEOGRAPHIC REFERENCE: 103 NM NORTHEAST OF TAIPEI, TAIWAN
   MOVEMENT PAST 6 HOURS: WESTWARD AT 10 KTS
   SIGNIFICANT WAVE HEIGHT: 14 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A SMALL,
WELL-DEFINED, BUT SHALLOW AND FULLY EXPOSED LOW-LEVEL CIRCULATION
(LLCC) ASSOCIATED WITH TROPICAL DEPRESSION (TD) 10W (FRANCISCO).
WHILE THE SYSTEM IS STILL TRANSITING WESTWARD OVER RELATIVELY WARM
(28-29 C) WATERS NORTH OF TAIWAN, MID-LEVEL DRY AIR ENTERING THE
STRUCTURE OF THE VORTEX IS CLEARLY PRESENT. THAT COMBINED WITH LOW
TO MODERATE (15-20 KTS) VERTICAL WIND SHEAR (VWS) AND WEAK OUTFLOW
ARE RESULTING IN OVERALL UNFAVORABLE ENVIRONMENT. THE INITIAL
POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE FULLY EXPOSED
LLCC PRESENT IN THE VISIBLE SATELLITE IMAGERY LOOP. THE INITIAL
INTENSITY OF 30 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON
AGENCY DVORAK AND OBJECTIVE ESTIMATES LISTED BELOW. TD 10W IS STILL 
EMBEDDED WITHIN A LARGE CYCLONIC ROTATION EXTENDING FROM OKINAWA IN
THE NORTH TO LUZON IN THE SOUTH AND CENTERED OVER TAIWAN. SURFACE
OBSERVATIONS NEAR TAIWAN INDICATE INTENSITY BELOW 20 KTS, HOWEVER
WINDS ASSOCIATED WITH THE NORTHWESTERN PERIPHERY OF THE AFOREMENTIONED 
LARGE CYCLONIC CIRCULATION OVERLAP WITH THE WIND FIELD OF TD 
FRANCISCO, PARTICULARLY ALONG THE COASTLINE OF CHINA, RESULTING IN A 
BAND OF ELEVATED WINDS TO THE NORTH AND NORTHWEST OF THE LLCC.

INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND
RADII).

CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE TO THE NORTH, AS WELL
AS IMPACTS FROM THE AFOREMENTIONED LARGE CYCLONIC CIRCULATION

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T1.5 - 25 KTS
   RJTD: T1.5 - 25 KTS
   RCTP: T1.5 - 25 KTS
   CIMSS SATCON: 40 KTS AT 250517Z
   CIMSS ADT: 25 KTS AT 250540Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: UNFAVORABLE
   VWS: 15-20 KTS
   SST: 28-29 CELSIUS
   OUTFLOW: WEAK POLEWARD
   OTHER FACTORS: DRY AIR ENTRAINMENT

ANALYSIS CONFIDENCE:
   INITIAL POSITION: HIGH
   INITIAL INTENSITY: MEDIUM
   INITIAL WIND RADII: NOT APPLICABLE

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.

FORECAST DISCUSSION: TD 10W IS FORECAST TO CONTINUE TO WEAKEN AND
DISSIPATE WITHIN THE NEXT 12-24 HOURS, AS IT APPROACHES NORTHERN
PORTION OF THE TAIWAN STRAIT. SIMULTANEOUSLY, REMNANTS OF TD 10W
MAY INTERACT WITH THE TROPICAL STORM 11W APPROACHING FROM THE
SOUTHEAST, RESULTING IN A SOUTHEASTWARD TURN, HOWEVER MAXIMUM WINDS
ARE EXPECTED TO FALL BELOW 20 KTS AT THAT TIME AND THEREFORE
CURRENT FORECAST EXTENDS ONLY OUT TO 24 HOURS. ADDITIONALLY, AROUND
THE SAME TIME, THE LARGE CYCLONIC CIRCULATION IS EXPECTED TO
REORIENT FROM A SOUTHWEST-NORTHEAST AXIS, TO A MORE ZONAL
REPRESENTATION, WHICH COULD RESULT IN A SLOW DOWN OF TD 10W AND
POTENTIAL SHARP SOUTHEASTWARD TURN, JUST PRIOR TO FULL DISSIPATION 
INTO THE LARGER, SYNOPTIC SCALE FLOW PATTERN.

MODEL DISCUSSION: NUMERICAL TRACK MODEL GUIDANCE IS IN GOOD
AGREEMENT THROUGH THE INITIAL 12 HOURS, HOWEVER SHORTLY AFTER THAT,
MOST TRACKERS LOSE THE VORTEX, OR INTERPRET THE CHANGES TO THE
STEERING PATTERN DIFFERENTLY. THEREFORE JTWC TRACK FORECAST IS
ASSESSED WITH MEDIUM CONFIDENCE. AT THE SAME TIME, INTENSITY
GUIDANCE IS IN GOOD AGREEMENT WITH QUICK WEAKENING OVER THE NEXT 24
HOURS, WITH MOST AVAILABLE MODELS INDICATING DISSIPATION. AS A
RESULT, JTWC INTENSITY FORECAST IS ASSESSED WITH HIGH CONFIDENCE
AND IS LAID CLOSE TO THE MULTI-MODEL CONSENSUS.

FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: MEDIUM
   INTENSITY 0 - 72 HR: HIGH//
NNNN