WTPQ32 RJTD 021800
RSMC TROPICAL CYCLONE PROGNOSTIC REASONING
REASONING NO.40 FOR STS 2509 KROSA (2509)
1.GENERAL COMMENTS
  STS KROSA IS LOCATED AT 39.1N, 148.1E. INFORMATION ON THE CURRENT
  POSITION IS BASED ON ANIMATED MSI AND SURFACE OBSERVATIONS.
  POSITIONAL ACCURACY IS FAIR. CENTRAL PRESSURE IS 975HPA AND
  MAXIMUM SUSTAINED WINDS NEAR THE CENTER ARE 50KNOTS. THE SYSTEM IS
  IN A NEUTRAL ENVIRONMENT FOR DEVELOPMENT UNDER THE INFLUENCE OF
  GOOD UPPER-LEVEL OUTFLOW, LOW SSTS 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 EAST-NORTHEASTWARD ALONG THE NORTHWESTERN
  PERIPHERY OF A MID-LEVEL SUB-TROPICAL HIGH. ANIMATED MSI SHOWS CB
  CLUSTERS GATHERING AROUND THE CSC. ANIMATED MSI SHOWS GOOD CLOUD
  CHARACTERISTICS OF ANTICYCLONIC OUTFLOW. WATER VAPOR IMAGERY SHOWS
  DRY AIR AROUND THE SYSTEM. NOAA-21/ATMS 85 GHZ MICROWAVE IMAGERY
  SHOWS THE SYSTEM HAS ACTIVE CONVECTIVE CLOUD CLUSTERS AROUND THE
  CSC.
3.TRACK FORECAST
  THE SYSTEM WILL MOVE EAST-NORTHEASTWARD ALONG THE PERIPHERY OF A
  MID-LEVEL SUB-TROPICAL HIGH UNTIL FT48. 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 WEAKEN UNTIL FT48 DUE TO THE INFLUENCE OF
  INTERACTION WITH LOW SSTS AND LOW TCHP. THE SYSTEM WILL TRANSFORM
  INTO AN EXTRATROPICAL CYCLONE BY FT48. THE INTENSITY FORECAST IS
  BASED ON A CONSENSUS OF GUIDANCE DATA INCLUDING GSM.
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