WTPQ32 RJTD 121800
RSMC TROPICAL CYCLONE PROGNOSTIC REASONING
REASONING NO. 4 FOR TS 2407 AMPIL (2407)
1.GENERAL COMMENTS
  A TD PREVIOUSLY LOCATED AT 23.3N, 136.6E HAS BEEN UPGRADED TO TS
  (AMPIL) STATUS. TS AMPIL IS LOCATED AT 23.7N, 136.8E. INFORMATION
  ON THE CURRENT POSITION IS BASED ON ANIMATED MSI. POSITIONAL
  ACCURACY IS FAIR. CENTRAL PRESSURE IS 998HPA AND MAXIMUM SUSTAINED
  WINDS NEAR THE CENTER ARE 35KNOTS. THE SYSTEM IS IN A FAVORABLE
  ENVIRONMENT FOR DEVELOPMENT UNDER THE INFLUENCE OF HIGH SSTS AND
  WEAK VWS. THIS HAS CAUSED THE SYSTEM TO DEVELOP OVER THE LAST SIX
  HOURS. INFORMATION ON THE CURRENT INTENSITY IS BASED ON DVORAK
  INTENSITY ANALYSES.
2.SYNOPTIC SITUATION
  THE SYSTEM IS MOVING SLOWLY NORTH-NORTHEASTWARD UNDER THE
  INFLUENCE OF LOW-LEVEL FLOW. ANIMATED MSI SHOWS CB CLUSTERS HAVE
  GATHERED AROUND THE CSC. WATER VAPOR IMAGERY SHOWS DRY AIR AROUND
  THE SYSTEM. METOP-C/MHS 85 GHZ MICROWAVE IMAGERY SHOWS THE SYSTEM
  HAS ACTIVE CONVECTIVE CLOUD CLUSTERS AROUND THE CSC.
3.TRACK FORECAST
  THE SYSTEM WILL MOVE NORTHEASTWARD ALONG THE PERIPHERY OF A
  MID-LEVEL SUB-TROPICAL HIGH UNTIL FT12. THE SYSTEM WILL THEN MOVE
  NORTH-NORTHEASTWARD UNTIL FT48. THE SYSTEM WILL THEN MOVE
  NORTHWARD UNTIL FT96. THE SYSTEM WILL THEN MOVE NORTHEASTWARD
  UNTIL FT120. THE TRACK FORECAST IS BASED ON GSM PREDICTIONS, AND
  REFERENCE TO OTHER NWP MODELS. TRACK FORECAST CONFIDENCE IS FAIR
  BECAUSE ALL NWP MODELS ARE IN CLOSE AGREEMENT.
4.INTENSITY FORECAST
  THE SYSTEM WILL DEVELOP UNTIL FT72 DUE TO THE INFLUENCE OF
  INTERACTION WITH HIGH SSTS AND WEAK VWS. THE SYSTEM WILL THEN
  WEAKEN UNTIL FT120 DUE TO THE INFLUENCE OF INTERACTION WITH LAND
  AND LOW TCHP. THE INTENSITY FORECAST IS BASED ON A CONSENSUS OF
  GUIDANCE DATA INCLUDING GSM.
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