WDXS33 PGTW 032100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 14S (TALIAH) WARNING NR 
006//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 15.4S 112.8E
   INITIAL INTENSITY: 75 KTS
   GEOGRAPHIC REFERENCE: 421 NM NORTH OF LEARMONTH, AUSTRALIA
   MOVEMENT PAST 6 HOURS: WESTWARD AT 10 KTS
   SIGNIFICANT WAVE HEIGHT: 30 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TROPICAL
CYCLONE 14S (TALIAH) WITH TIGHTLY WRAPPING BANDS OF DEEP
CONVECTION, CURRENTLY FULLY OBSCURING THE LOW-LEVEL CIRCULATION
CENTER (LLCC). DESPITE 20-25 KTS EASTERLY VERTICAL WIND SHEAR
(VWS), THE WESTWARD AND EQUATORWARD OUTFLOW IS MODERATE.
ENVIRONMENTAL ANALYSIS REVEALS FAVORABLE CONDITIONS, WITH
DECREASING VWS AND VERY WARM (29-30 C) SEA SURFACE TEMPERATURES
(SST). THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED
ON THE 031347 AMSUB MICROWAVE PASS, CONSISTENT WITH THE 031048Z SAR
DATA EXTRAPOLATION. THE INITIAL INTENSITY OF 75 KTS IS ASSESSED
WITH HIGH CONFIDENCE BASED ON THE AFOREMENTIONED SAR PASS, AS WELL
AS THE AGENCY FIXES AND OBJECTIVE AIDS LISTED BELOW.

INITIAL WIND RADII BASIS: 031048Z SAR DATA 

CURRENT STEERING MECHANISM: NORTHERN PERIPHERY OF A SUBTROPICAL
RIDGE (STR) TO THE SOUTH

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T4.5 - 77 KTS
   KNES: T4.0 - 65 KTS
   DEMS: T4.0 - 65 KTS
   APRF: T4.0 - 65 KTS
   CIMSS SATCON: 76 KTS AT 031753Z
   CIMSS ADT: 79 KTS AT 031730Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 15-20 KTS
   SST: 28-29 CELSIUS
   OUTFLOW: MODERATE RADIAL

ANALYSIS CONFIDENCE:
   INITIAL POSITION: MEDIUM
   INITIAL INTENSITY: HIGH
   INITIAL WIND RADII: MEDIUM

3. FORECAST REASONING.

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

FORECAST DISCUSSION: TROPICAL CYCLONE 14S IS FORECAST TO TRACK
WESTWARD, CONTINUING ALONG THE NORTHERN PERIPHERY OF THE
SUBTROPICAL RIDGE TO THE SOUTH, THROUGHOUT TAU 72. AFTER THAT, MOST
GUIDANCE PREDICTS A SLIGHT WEST-SOUTHWESTWARD TURN, AS THE STEERING
WEAKENS. IN TERMS OF INTENSITY, TC 14S IS EXPECTED TO SLIGHTLY
INTENSIFY OVER THE NEXT 12 HOURS, FOLLOWED BY A PERIOD OF SUSTAINED
75 KTS MAX WINDS THROUGH TAU 48. PAST THAT THE SEA SURFACE
TEMPERATURES WILL DROP, WHICH EFFECTS WILL BE AMPLIFIED BY THE TC
14S TRACKING DIRECTLY THROUGH THE COLD WAKE LEFT BEHIND BY
TC 13S. AS A RESULT, TC 14S IS FORECAST TO CONTINUE WEAKENING
THROUGHOUT TAU 120.

MODEL DISCUSSION: NUMERICAL MODEL TRACK GUIDANCE IS IN GOOD
AGREEMENT THROUGH TAU 72, WITH THE CROSS-TRACK SPREAD OF 65NM,
AFTER WHICH THE TRACK GUIDANCE DIVERGES TO 250 NM CROSS-TRACK
SPREAD. JTWC FORECAST IS LAID CLOSELY TO THE MULTI-MODEL CONSENSUS,
WITH HIGH CONFIDENCE THROUGH TAU 72, AND MEDIUM CONFIDENCE TOWARDS
THE END OF THE FORECAST PERIOD. INTENSITY GUIDANCE IS IN POOR
AGREEMENT OVER THE NEXT 36 HOURS, WITH COAMPS-TC SUGGESTING A PEAK
INTENSITY OF 80-85 KTS BY TAU 12, WHILE GFS PREDICTING A SLIGHT
WEAKENING FOLLOWED BY A PEAK OF INTENSIFICATION BY TAUS 36-48. HAFS
GUIDANCE AT THE SAME TIME PREDICTS STEADY WEAKENING, BEGINNING
IMMEDIATELY. JTWC FORECAST GUIDANCE IS THEREFORE ASSESSED IN CLOSE
PROXIMITY TO MULTI-MODEL CONSENSUS SUGGESTING AN INITIAL UPTICK IN
INTENSITY OVER THE NEXT 12-24 HOURS, FOLLOWED BY STEADY AND SLOW
WEAKENING, UNTIL TAU 72. AFTER THAT, INTENSITY GUIDANCE IS HIGHLY
SPREAD OUT AND WILL DEPEND ON THE ACTUAL TRACK AND IMPACTS FROM THE
COOLER SEA SURFACE TEMPERATURES ASSOCIATED WITH THE TC 13S.

FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: HIGH
   TRACK 72-120 HR: MEDIUM
   INTENSITY 0 - 72 HR: MEDIUM
   INTENSITY 72-120 HR: LOW//
NNNN