WTPQ32 RJTD 270000
RSMC TROPICAL CYCLONE PROGNOSTIC REASONING
REASONING NO.13 FOR TY 2509 KROSA (2509)
1.GENERAL COMMENTS
  TY KROSA IS LOCATED AT 20.4N, 145.4E. INFORMATION ON THE CURRENT
  POSITION IS BASED ON ANIMATED MSI AND SURFACE OBSERVATIONS.
  POSITIONAL ACCURACY IS FAIR. CENTRAL PRESSURE IS 965HPA AND
  MAXIMUM SUSTAINED WINDS NEAR THE CENTER ARE 75KNOTS. THE SYSTEM IS
  IN A FAVORABLE ENVIRONMENT FOR DEVELOPMENT UNDER THE INFLUENCE OF
  HIGH SSTS, HIGH TCHP AND GOOD UPPER-LEVEL OUTFLOW. THIS HAS CAUSED
  THE SYSTEM TO DEVELOP 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 NORTHWARD ALONG THE WESTERN PERIPHERY OF A
  MID-LEVEL SUB-TROPICAL HIGH. ANIMATED MSI SHOWS THE FORMATION OF A
  CDO PATTERN. ANIMATED MSI SHOWS THE CLOUD CHARACTERISTICS OF
  ANTICYCLONIC OUTFLOW ARE NOW DISTINCT. WATER VAPOR IMAGERY SHOWS
  DRY AIR AROUND THE SYSTEM. DMSP-F18/SSMIS 89 GHZ MICROWAVE IMAGERY
  SHOWS THE SYSTEM HAS A BAND WITH CURVATURE INDICATING THE CSC.
3.TRACK FORECAST
  THE SYSTEM WILL MOVE NORTHWARD ALONG THE PERIPHERY OF A MID-LEVEL
  SUB-TROPICAL HIGH UNTIL FT24. THE SYSTEM WILL THEN GRADUALLY
  DECELERATE AND MOVE NORTH-NORTHWESTWARD ALONG THE PERIPHERY OF A
  MID-LEVEL SUB-TROPICAL HIGH UNTIL FT48. THE SYSTEM WILL THEN
  REMAIN ALMOST STATIONARY BETWEEN TWO MID-LEVEL SUB-TROPICAL HIGHS
  UNTIL FT96. THE SYSTEM WILL THEN MOVE SLOWLY NORTH-NORTHEASTWARD
  BETWEEN TWO MID-LEVEL SUB-TROPICAL HIGHS 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 MAINTAIN ITS INTENSITY UNTIL FT24 DUE TO THE
  INSUFFICIENT ENVIRONMENT FOR ITS FURTHER DEVELOPMENT DESPITE A
  FAVORABLE ENVIRONMENT UNDER THE INFLUENCE OF INTERACTION WITH HIGH
  SSTS AND GOOD UPPER-LEVEL OUTFLOW. THE SYSTEM WILL THEN GRADUALLY
  WEAKEN UNTIL FT48 DUE TO THE INFLUENCE OF INTERACTION WITH LOWER
  SSTS AND REDUCED TCHP. THE SYSTEM WILL THEN GRADUALLY WEAKEN UNTIL
  FT96 DUE TO ITS PRESENCE OVER THE SAME WATERS. THE SYSTEM WILL
  THEN MAINTAIN ITS INTENSITY UNTIL FT120 DUE TO THE INFLUENCE OF
  INTERACTION WITH WEAK VWS AND LOW TCHP. THE INTENSITY FORECAST IS
  BASED ON A CONSENSUS OF GUIDANCE DATA INCLUDING GSM.
=