WDIO31 PGTW 242100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 03B (DANA) WARNING NR
007//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 20.2N 87.2E
   INITIAL INTENSITY: 65 KTS
   GEOGRAPHIC REFERENCE: 159 NM SOUTH-SOUTHWEST OF KOLKATA, INDIA
   MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 05 KTS
   SIGNIFICANT WAVE HEIGHT: 24 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A WELL
DEFINED TROPICAL CYCLONE WITH PERSISTENT, THOUGH FLARING DEEP
CONVECTION OBSCURING THE LLCC. ANIMATED RADAR IMAGERY AND A 241751Z
SCATTEROMETERY IMAGE INDICATES THAT 03B IS MEER HOURS FROM MAKING
LANDFALL OVER EASTERN INDIA. THE INITIAL POSITION IS PLACED WITH
MEDIUM CONFIDENCE BASED ON EIR, SCATTEROMETERY AND ANIMATED RADAR
IMAGERY. THE INITIAL INTENSITY OF 65 KTS IS ASSESSED WITH MEDIUM
CONFIDENCE BASED ON A RANGE OF AGENCY DVORAK AND CIMSS AUTOMATED
INTENSITY ESTIMATES INDICATING 55-67KTS.

INITIAL WIND RADII BASIS: SCATTEROMETER DATA

CURRENT STEERING MECHANISM: WESTERN PERIPHERY OF A SUBTROPICAL
RIDGE (STR) OVER EASTERN MYANMAR.

AGENCY DVORAK AND AUTOMATED FIXES:
   PGTW: T3.5 - 55 KTS
   KNES: T3.5 - 55 KTS
   DEMS: T3.5 - 55 KTS
   CIMSS SATCON: 56 KTS AT 241332Z
   CIMSS ADT: 61 KTS AT 241800Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE
   VWS: 5-10 KTS
   SST: 29-30 CELSIUS
   OUTFLOW: MODERATE EQUATORWARD

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

3. FORECAST REASONING.

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

FORECAST DISCUSSION: TC 03B (DANA) IS ONLY A FEW HOURS FROM MAKING
LANDFALL OVER EASTERN INDIA. THE SYSTEM WILL MAKE LANDFALL NEAR
65KTS AND QUICKLY WEAKEN AS IT TRANSITS OVER MAINLAND INDIA. AS THE
SYSTEM PROCEEDS INLAND, A BUILDING SUBTROPICAL RIDGE TO THE WEST
ASSERTS ITS INFLUENCE BY REDIRECTING 02B WESTWARD AND EVENTUALLY
WEST-SOUTHWESTWARD AS IS DISSIPATES NEAR TAU 48.

MODEL DISCUSSION: NUMERICAL MODELS ARE IN GOOD AGREEMENT THAT 03B
WILL MAKE LANDFALL BEFORE TAU 12 AND QUICKLY DIVERT WESTWARD AND
EVENTUALLY WEST-SOUTHWESTWARD THROUGH DISSIPATION. RELIABLE MODEL
INTENSITY GUIDANCE IS UNANIMOUSLY INDICATING A SHARP DISSIPATION
TREND FOLLOWING LANDFALL. FOR THESE REASONS BOTH THE JTWC TRACK AND
INTENSITY FORECASTS ARE PLACED WITH HIGH CONFIDENCE.

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