WTPQ30 RJTD 081800
RSMC TROPICAL CYCLONE PROGNOSTIC REASONING
REASONING NO.18 FOR TY 2014 CHAN-HOM (2014)
1.GENERAL COMMENTS
TY CHAN-HOM IS LOCATED AT 30.1N, 133.5E. 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 70KNOTS.
THE SYSTEM IS IN A NEUTRAL ENVIRONMENT FOR DEVELOPMENT UNDER THE
INFLUENCE OF GOOD UPPER-LEVEL OUTFLOW AND DRY AIR. 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 NORTHWARD ALONG THE WESTERN PERIPHERY OF A
MID-LEVEL SUB-TROPICAL HIGH. ANIMATED MSI SHOWS THE SYSTEM HAS A
BAND WITH A CURVATURE SUGGESTING THE CSC. ANIMATED MSI SHOWS GOOD
CLOUD CHARACTERISTICS OF ANTICYCLONIC OUTFLOW. WATER VAPOR IMAGERY
SHOWS DRY AIR IN THE DIRECTION OF THE MOVEMENT.
3.TRACK FORECAST
THE SYSTEM WILL MOVE NORTHEASTWARD ALONG THE PERIPHERY OF A
MID-LEVEL SUB-TROPICAL HIGH UNTIL FT24. THE SYSTEM WILL THEN
GRADUALLY ACCELERATE AND MOVE EAST-NORTHEASTWARD UNDER THE
INFLUENCE OF MID-LATITUDE PREVAILING WESTERLIES UNTIL FT96. THE
TRACK FORECAST IS BASED ON GSM PREDICTIONS, AND REFERENCE TO OTHER
NWP MODELS. TRACK FORECAST CONFIDENCE IS FAIR UNTIL FT24 BUT LOW
THEREAFTER DUE TO SIGNIFICANT DIFFERENCES AMONG NWP MODEL OUTPUTS. 4.INTENSITY FORECAST
THE SYSTEM WILL MAINTAIN ITS INTENSITY UNTIL FT12 DUE TO THE
INFLUENCE OF INTERACTION WITH GOOD UPPER LEVEL OUTFLOW AND DRY
AIR. THE SYSTEM WILL THEN WEAKEN UNTIL FT96 DUE TO THE INFLUENCE
OF INTERACTION WITH LOWER SSTS, REDUCED TCHP AND INCREASED VWS.
THE SYSTEM WILL TRANSFORM INTO AN EXTRATROPICAL CYCLONE BY FT96.
THE INTENSITY FORECAST IS BASED ON GSM PREDICTIONS.
=
--- SBBSecho 3.11-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (21:1/175)