TC 02A(BIPARJOY) up-graded to CAT 3 US based on SAR//TY 03W(GUCHOL) peaked at CAT 2 US//1112utc

JTWC IS ISSUING 6HOURLY WARNINGS AND 3HOURLY SATELLITE BULLETINS ON TY 03W(GUCHOL) AND TC 02A(BIPARJOY).

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS AN ERODING CENTRAL DENSE OVERCAST (CDO), WHICH IS EXPOSING THE LOW LEVEL CLOUD LINES TO THE WEST OF THE LLCC. A 110617Z SSMIS 91GHZ MICROWAVE IMAGE INDICATES AN ASYMMETRIC CIRCULATION WITH CONVECTIVE ACTIVITY LIMITED TO THE EASTERN SEMICIRCLE. A RECENT 110419Z SCATTEROMETRY IMAGE REVEALS THAT MUCH LIKE THE CONVECTIVE ACTIVITY, THE HIGHEST WINDS ARE WITHIN THE SAME EASTERN QUADRANT. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON MSI AND SSMIS IMAGERY. THE INITIAL INTENSITY OF 85 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON THE CONFIRMED LOW BIAS OF DVORAK AND AUTOMATED INTENSITY ESTIMATES WHEN COMPARED WITH PREVIOUS 102113Z SYNTHETIC APERTURE RADAR (SAR) AND SMAP SCALER WIND DATA FROM THE SAME TIME. WHILE THE MAGNITUDE OF THE OTHER INTENSITY DATA IS SUSPECT, THE RECENT TRENDS HAVE ALL HELD GENERALLY SIMILAR AND COUPLED WITH NO SIZABLE CONVECTIVE CHANGES, THE RESULT IS 03W LIKELY HOLDING INTENSITY AT 85KTS.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TY 03W IS FORECAST TO CONTINUE ITS GRADUAL TURN NORTHEASTWARD THROUGH THE FORECAST PERIOD. AS THE SYSTEM TRACKS POLEWARD, A CLASSIC BATTLE BETWEEN IMPROVING OUTFLOW, COOLING SSTS AND INCREASING VERTICAL WIND SHEAR (VWS) WILL BEGIN. AT THE MOMENT, THE SYSTEM IS GENERALLY REBUFFING THE NEGATIVE EFFECTS OF PERSISTENT MODERATE VWS AND MID LEVEL DRY AIR ENTRAINMENT. OVER THE NEXT 12 HOURS, THE OUTFLOW CHANNEL TO THE EAST WILL CUTOFF AND THE SYSTEM WILL BEGIN TO TAP INTO THE JET STREAM TO THE NORTH. DURING THIS SAME TIME HOWEVER, VWS AND DRY AIR ENTRAINMENT WILL INCREASE AND SSTS WILL CONTINUE TO FALL. THE RESULTS OF THIS WILL BE INITIALLY GRADUAL WEAKENING THAT WILL ESCALATE WITH TIME. AS THE SYSTEM INTERACTS WITH THE JET STREAM, THE HIGH SHEAR VALUES AND BAROCLINIC REGIONS ASSOCIATED WITH IT WILL TEAR THE SYSTEM APART AND QUICKLY PROGRESS 03W THROUGH SUB-TROPICAL TRANSITION (STT) THROUGH TAU 36. AS THE SYSTEM SPEEDS OFF TO THE NORTHEAST, IT WILL BE STRIPPED OF ALL REMAINING TROPICAL CHARACTERISTICS AND EVENTUALLY COMPLETE EXTRA-TROPICAL TRANSITION (ETT) BY TAU 72, ALL THE WHILE CONTINUING TO WEAKEN.

MODEL DISCUSSION: NUMERICAL MODELS ARE IN TIGHT AGREEMENT THROUGH THE FORECAST PERIOD WITH MINIMAL CROSS TRACK OR ALONG TRACK SPREADING. AS A RESULT THE JTWC FORECAST TRACK IS PLACED WITH HIGH CONFIDENCE. SIMILARLY, RELIABLE MODEL INTENSITY GUIDANCE IS IN GOOD AGREEMENT WITH ALL MEMBERS FOLLOWING CLOSELY TO THE JTWC FORECAST INTENSITY, WHICH IS ALSO PLACED WITH HIGH CONFIDENCE.

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS THAT 02A IS ONCE AGAIN FIGHTING TO REFORM AND CLEAR OUT AN EYE FEATURE. DEEP FLARING CONVECTION HAS RECENTLY EXPANDED AND RECENTERED ITSELF OVER THE NOW FULLY OBSCURED LLCC. A FORTUITOUS 110547Z GMI SUITE OF MICROWAVE IMAGES, SPECIFICALLY THE 89GHZ AND 37GHZ COLOR COMPOSITE, REVEALS THAT THE LLCC AND ULCC HAVE REALIGNED VERTICALLY WHICH IS HELPING TO FUEL ITS INTENSIFICATION. AN 110455Z ASCAT-B SCATTEROMETRY PASS SHOWS A HIGHLY SYMMETRIC WIND FIELD WITH A SMALL COMPACT CIRCULATION. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON MSI, GMI AND SCATTEROMETRY DATA. THE INITIAL INTENSITY OF 105 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON A HEDGE ABOVE AGENCY DVORAK INTENSITY ESTIMATES WHICH MAINTAIN T5.0 DESPITE PREVIOUS SYNTHETIC APERTURE RADAR (SAR) AND SMAP SCALAR WIND DATA INDICATING UPWARDS OF 100KTS. SINCE THESE AFOREMENTIONED HIGH RESOLUTION PASSES, THE CONVECTIVE ORGANIZATION OF 02A HAS IMPROVED AND A WELL DEFINED MICROWAVE EYE IN BOTH FREQUENCY RANGES DISCUSSED ABOVE STRONGLY INDICATES INTENSIFICATION IS ONGOING.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TC 02A IS FORECAST TO CONTINUE GENERALLY NORTHWARD UNDER THE STEERING INFLUENCE OF THE STR TO THE EAST. CURRENTLY IN A MARGINALLY FAVORABLE ENVIRONMENT, 02A HAS DEMONSTRATED A PROCLIVITY FOR INTENSIFICATION DESPITE NEARLY 30KTS OF VERTICAL WIND SHEAR. OVER THE PAST SIX HOURS, 02A HAS REDUCED ITS VERTICAL TILT AND LARGELY RECONSOLIDATED ITS CONVECTIVE COVER NEARLY TO THE POINT OF FORMING AN EYE IN VISIBLE IMAGERY. IF THE SYSTEM CAN MAINTAIN THIS TREND WHILE THE OUTFLOW PATH TO THE WEST IS AVAILABLE, THE POSSIBILITY FOR SHORT TERM INTENSIFICATION THROUGH TAU 12 CANNOT BE RULED OUT. AS THE SYSTEM PROGRESSES POLEWARD, THE WESTWARD OUTFLOW CHANNEL IS CUTOFF AND REPLACED WITH SUBSIDENCE ALOFT, WHICH TOGETHER WITH NEARLY 30KTS OF VWS AND DRY AIR ENTRAINMENT WILL WEAKENING THE SYSTEM THROUGH TAU 72. AFTER TAU 72, THE SYSTEM WILL TURN NORTHEASTWARD AND MAKE LANDFALL AS THE STR REORIENTS. THROUGH THE FORECAST PERIOD THE SYSTEM WILL BE EVISCERATED AS IT PROCEEDS INLAND, RAPIDLY WEAKENING TO 45KTS BY TAU 120.

MODEL DISCUSSION: NUMERICAL MODELS ARE IN GOOD AGREEMENT THROUGH TAU 72 WITH ALL MEMBERS GENERALLY FOLLOWING THE JTWC FORECAST TRACK. AFTER TAU 72 THERE IS A SLIGHT SPREAD IN THE MODEL GUIDANCE AS THE TIMING AND DEGREE OF THE NORTHEASTWARD TURN VARIES BETWEEN MEMBERS. FOR THIS REASON THE JTWC TRACK FORECAST IS PLACED INITIALLY WITH HIGH CONFIDENCE AND WITH MEDIUM CONFIDENCE THEREAFTER. RELIABLE MODEL INTENSITY GUIDANCE IS IN POOR AGREEMENT WITH HWRF THE ONLY MEMBERS THAT SEEMS TO BE CAPTURING THE RECENT INTENSIFICATION AND POSSIBLE NEAR TERM UPWARD TRAJECTORY. THE REMAINING MODEL GUIDANCE AS WELL AS COAMPS-TC THE OTHER COUPLED OCEAN ATMOSPHERIC MODEL SHARPLY WEAKEN THE SYSTEM THROUGH THE FORECAST PERIOD LEAVING A GROWING DISPARITY IN UPPER AND LOWER BOUNDS AS TIME PROGRESSES. BASED ON RECENT TRENDS IN BOTH CONVECTION AND AXIAL CONSOLIDATION AS WELL AS THE AFOREMENTIONED SAR AND SMAP DATA. MORE CREDENCE IS PLACED IN THE INITIAL TREND OF HWRF, AFTER WHICH THE JTWC INTENSITY FORECAST CLOSELY FOLLOWS THE TRENDS OF THE REMAINING CONSENSUS MEMBERS, ALBEIT WITH OVERALL LOW CONFIDENCE.