Météo974
WESTERN NORTH PACIFIC
TS KROSA(11W)
Location: 35.9°N 133.1°E
Maximum Winds: 40 kt ( 75km/h)
Gusts: 50 kt (95km/h)
Minimum Central Pressure: 979 mb
WDPN33 PGTW 151500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 11W (KROSA) WARNING NR
040//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 11W (KROSA), LOCATED APPROXIMATELY 108 NM
NORTH-NORTHEAST OF IWAKUNI, JAPAN, HAS TRACKED NORTH-NORTHEASTWARD AT
18 KNOTS KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY SHOWS THE SYSTEM CONTINUED TO ERODE AND UNRAVEL AS
IT EXITED INTO THE SEA OF JAPAN (SOJ). THE INITIAL POSITION IS PLACED
WITH HIGH CONFIDENCE BASED ON A BROAD AND RAGGED LOW LEVEL
CIRCULATION (LLC) THAT IS WELL-DEFINED IN THE COMPOSITE REFLECTIVITY
RADAR LOOP FROM JMA. THE INITIAL INTENSITY IS BASED ON AN OVERALL
ASSESSMENT OF AGENCY DVORAK ESTIMATES AND NUMEROUS SURFACE
OBSERVATIONS, INCLUDING THOSE FROM SAIGO ISLAND, 15NM TO THE NORTH.
UPPER LEVEL ANALYSIS INDICATES MODERATE (15-20KT) VERTICAL WIND SHEAR
(VWS) THAT IS PARTLY OFFSET BY STRONG POLEWARD OUTFLOW. TS 11W IS
TRACKING ALONG THE WESTERN EDGE OF A SUBTROPICAL RIDGE (STR) TO THE
EAST.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. TS KROSA IS EXPECTED TO ACCELERATE NORTHEASTWARD ON THE
POLEWARD SIDE OF THE STR TOWARD HOKKAIDO. THE ADDITION OF COOLER SST
IN THE SOJ WILL ENHANCE THE CONVECTIVE DEGRADATION; HOWEVER, THE LLC
WILL RETAIN ITS CURRENT INTENSITY UP TO TAU 24. CONCURRENTLY, THE
SYSTEM WILL NOW BEGIN EXTRA-TROPICAL TRANSITION, BECOMING A
GALE-FORCE COLD CORE LOW WITH AN EXPANSIVE WIND FIELD BY TAU 24.
DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT, LENDING HIGH CONFIDENCE
IN THE JTWC FORECAST TRACK.//
NNNN
M974World
WESTERN NORTH PACIFIC
TS KROSA(11W)
Location: 35.9°N 133.1°E
Maximum Winds: 40 kt ( 75km/h)
Gusts: 50 kt (95km/h)
Minimum Central Pressure: 979 mb
WDPN33 PGTW 151500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 11W (KROSA) WARNING NR
040//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 11W (KROSA), LOCATED APPROXIMATELY 108 NM
NORTH-NORTHEAST OF IWAKUNI, JAPAN, HAS TRACKED NORTH-NORTHEASTWARD AT
18 KNOTS KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY SHOWS THE SYSTEM CONTINUED TO ERODE AND UNRAVEL AS
IT EXITED INTO THE SEA OF JAPAN (SOJ). THE INITIAL POSITION IS PLACED
WITH HIGH CONFIDENCE BASED ON A BROAD AND RAGGED LOW LEVEL
CIRCULATION (LLC) THAT IS WELL-DEFINED IN THE COMPOSITE REFLECTIVITY
RADAR LOOP FROM JMA. THE INITIAL INTENSITY IS BASED ON AN OVERALL
ASSESSMENT OF AGENCY DVORAK ESTIMATES AND NUMEROUS SURFACE
OBSERVATIONS, INCLUDING THOSE FROM SAIGO ISLAND, 15NM TO THE NORTH.
UPPER LEVEL ANALYSIS INDICATES MODERATE (15-20KT) VERTICAL WIND SHEAR
(VWS) THAT IS PARTLY OFFSET BY STRONG POLEWARD OUTFLOW. TS 11W IS
TRACKING ALONG THE WESTERN EDGE OF A SUBTROPICAL RIDGE (STR) TO THE
EAST.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. TS KROSA IS EXPECTED TO ACCELERATE NORTHEASTWARD ON THE
POLEWARD SIDE OF THE STR TOWARD HOKKAIDO. THE ADDITION OF COOLER SST
IN THE SOJ WILL ENHANCE THE CONVECTIVE DEGRADATION; HOWEVER, THE LLC
WILL RETAIN ITS CURRENT INTENSITY UP TO TAU 24. CONCURRENTLY, THE
SYSTEM WILL NOW BEGIN EXTRA-TROPICAL TRANSITION, BECOMING A
GALE-FORCE COLD CORE LOW WITH AN EXPANSIVE WIND FIELD BY TAU 24.
DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT, LENDING HIGH CONFIDENCE
IN THE JTWC FORECAST TRACK.//
NNNN
15/12UTC
15/1114UTC
TRACK AND INTENSITY GUIDANCE
