WTPQ32 RJTD 280600
RSMC TROPICAL CYCLONE PROGNOSTIC REASONING
REASONING NO.18 FOR TY 2509 KROSA (2509)
1.GENERAL COMMENTS
  TY KROSA IS LOCATED AT 26.9N, 144.6E. INFORMATION ON THE CURRENT
  POSITION IS BASED ON ANIMATED MSI AND SURFACE OBSERVATIONS.
  POSITIONAL ACCURACY IS GOOD. CENTRAL PRESSURE IS 965HPA AND
  MAXIMUM SUSTAINED WINDS NEAR THE CENTER ARE 75KNOTS. THE SYSTEM IS
  IN A NEUTRAL ENVIRONMENT FOR DEVELOPMENT UNDER THE INFLUENCE OF
  GOOD UPPER-LEVEL OUTFLOW, WEAK VWS AND LOW TCHP. THIS HAS CAUSED
  THE SYSTEM TO MAINTAIN ITS INTENSITY OVER THE LAST SIX HOURS.
  INFORMATION ON THE CURRENT INTENSITY IS BASED ON DVORAK INTENSITY
  ANALYSES AND SURFACE OBSERVATIONS.
2.SYNOPTIC SITUATION
  THE SYSTEM IS MOVING NORTH-NORTHWESTWARD ALONG THE SOUTHWESTERN
  PERIPHERY OF A MID-LEVEL SUB-TROPICAL HIGH. ANIMATED MSI SHOWS THE
  SHORTENING OF A BAND WITH CURVATURE SUGGESTING THE CSC. ANIMATED
  MSI SHOWS THE CLOUD CHARACTERISTICS OF ANTICYCLONIC OUTFLOW ARE
  NOW DISTINCT. WATER VAPOR IMAGERY SHOWS DRY AIR AROUND THE SYSTEM.
  GPM/GMI 89 GHZ MICROWAVE IMAGERY SHOWS THE SYSTEM HAS A BAND WITH
  CURVATURE INDICATING THE CSC.
3.TRACK FORECAST
  THE SYSTEM WILL MOVE NORTH-NORTHWESTWARD ALONG THE PERIPHERY OF A
  MID-LEVEL SUB-TROPICAL HIGH UNTIL FT24. THE SYSTEM WILL THEN
  REMAIN ALMOST STATIONARY ALONG THE PERIPHERY OF A MID-LEVEL
  SUB-TROPICAL HIGH UNTIL FT48. THE SYSTEM WILL THEN MOVE SLOWLY
  NORTHEASTWARD ALONG THE PERIPHERY OF A MID-LEVEL SUB-TROPICAL HIGH
  UNTIL FT72. THE SYSTEM WILL THEN GRADUALLY TURN TO THE NORTH ALONG
  THE PERIPHERY OF A MID-LEVEL SUB-TROPICAL HIGH UNTIL FT120. THE
  TRACK FORECAST IS BASED ON GSM PREDICTIONS, AND REFERENCE TO OTHER
  NWP MODELS. TRACK FORECAST CONFIDENCE IS FAIR UNTIL FT48 BUT LOW
  THEREAFTER DUE TO SIGNIFICANT DIFFERENCES AMONG NWP MODEL OUTPUTS.
4.INTENSITY FORECAST
  THE SYSTEM WILL WEAKEN UNTIL FT12 DUE TO THE INFLUENCE OF LOW
  TCHP. THE SYSTEM WILL THEN MAINTAIN ITS INTENSITY UNTIL FT24 DUE
  TO THE INFLUENCE OF INTERACTION WITH GOOD UPPER-LEVEL OUTFLOW,
  WEAK VWS AND LOW TCHP. THE SYSTEM WILL THEN GRADUALLY WEAKEN UNTIL
  FT120 DUE TO THE INFLUENCE OF LOW TCHP. THE INTENSITY FORECAST IS
  BASED ON A CONSENSUS OF GUIDANCE DATA INCLUDING GSM.
=