TC 11S(FREDDY) intensifying and making landfall within 24h near Quelimane-MOZ//Invest 99P Tropical Cyclone Formation Alert//1015utc

JTWC IS ISSUING 12HOURLY WARNINGS AND 3HOURLY SATELLITE BULLETINS ON TC 11S(FREDDY). 3HOURLY SATELLITE BULLETINS ARE ISSUED ON INVEST 99P.

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS FRAGMENTED BANDING CIRCLING A MASS OF CONVECTION BLOOMING OVER AN ASSESSED LOW LEVEL CIRCULATION CENTER (LLCC). A BULLSEYE 100711Z ASCAT-B PASS HAS REVEALED THE 35 KNOT WIND FIELD HAS DECREASED IN DIAMETER OVER THE PAST 12 HOURS AS TC FREDDY MAKES ITS APPROACH TO SHORE. TC FREDDY IS IN A MARGINALLY FAVORABLE ENVIRONMENT FOR FURTHER TROPICAL DEVELOPMENT. THESE CONDITIONS ARE CHARACTERIZED BY LOW (05-10 KTS) VERTICAL WIND SHEAR (VWS), A HEALTHY 850 MB VORTICITY SIGNATURE, AND VERY WARM (27-28 C) SEA SURFACE TEMPERATURES (SST), OFFSET BY THE LACK OF UPPER-LEVEL OUTFLOW. THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED ON THE AFOREMENTIONED MSI AND MULTI-AGENCY FIXES. THE INITIAL INTENSITY OF 65 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED OFF A BLEND OF MULTI-AGENCY AND AUTOMATED DVORAK ESTIMATES.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TC FREDDY IS IN A TUG-OF-WAR BETWEEN THE NER TO THE NORTHEAST AND THE STR TO THE SOUTHWEST. BY TAU 12, TC 11S WILL INCREASE IN INTENSITY TO 70 KTS DUE TO AN IMPROVING STRUCTURE AND ENTERING AN INCREASINGLY FAVORABLE ENVIRONMENT JUST BEFORE LANDFALL NEAR QUELIMANE, MOZAMBIQUE. BY TAU 24, TC FREDDY WILL CONTINUE TO INTENSIFY TO 75 KNOTS SHORTLY AFTER LANDFALL. TC 11S WILL THEN WEAKEN IN INTENSITY DUE TO LAND INTERACTION THROUGHOUT THE DURATION OF THE FORECAST AS THE REMNANTS WILL MAKE A DRAMATIC TURN BACK TO THE EAST-SOUTHEAST AFTER TAU 48.

OVER THE PAST SEVERAL MODEL RUNS, ONLY A HANDFUL OF THE JTWC TRACK CONSENSUS MEMBERS SUGGESTED AN ALMOST 180 DEGREE TURN IN TRAJECTORY AFTER LAND FALL. HOWEVER, NOW ALL CONSENSUS MEMBERS ARE IN AGREEMENT THAT TC FREDDY WILL MAKE A TURN NORTHWARD, FOLLOWED BY ANOTHER TURN EAST-SOUTHEASTWARD AND HEAD BACK TOWARDS THE MOZAMBIQUE CHANNEL. HOWEVER, THEY DISAGREE WITH THE TIMING OF THIS EVENT AS THEY ARE STILL TRYING TO FIGURE OUT THE BEHAVIOR OF THE NER TO THE NORTHEAST. THE GFS DETERMINISTIC AND ENSEMBLE SOLUTIONS DISPLAY THE FASTEST TRACK SPEEDS WITH INDICATIONS THAT TC 11S WILL BE BACK OVER THE MOZAMBIQUE CHANNEL BY TAUS 96 AND 120. ALL OF THE OTHER MEMBERS ARE STILL OVER LAND AT TAU 120, BUT WITH THE MOZAMBIQUE CHANNEL DOWNSTREAM OF THEIR TRACKS. DUE TO THIS DISPARITY IN THE MODELS, THE JTWC FORECAST TRACK IS SET WITH LOW CONFIDENCE. THE JTWC INTENSITY CONSENSUS MEMBERS ALL AGREE ON AN INTENSIFYING SCENARIO UP TO AND INCLUDING LANDFALL, THEN A DECREASE AFTERWARDS. THE JTWC INTENSITY FORECAST IS SET WITH MEDIUM CONFIDENCE.

THE AREA OF CONVECTION (INVEST 99P) PREVIOUSLY LOCATED NEAR 19.2S 168.8W IS NOW LOCATED NEAR 19.4S 167.1W, APPROXIMATELY 161 NM EAST OF NIUE. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) AND A 0100041Z AMSR2 GW1 89GHZ MICROWAVE IMAGE REVEALS A FULLY OBSCURED LLC WITH BUILDING CONVECTION OVERHEAD AND TO THE SOUTH. A PARTIAL 092103Z ASCAT-B PASS REVEALED A LARGE SWATH OF 15-20 KNOT WIND FIELDS ALONG THE WESTERN EDGES AND SMALLER FIELDS OF 25-30 KNOTS NEAR THE LLCC. INVEST 99P CONTINUES TO BE DEEPLY EMBEDDED WITHIN THE SPCZ, AND ENVIRONMENTAL CONDITIONS ARE FAVORABLE WITH WARM (27-28C) SEA SURFACE TEMPERATURES, EXCELLENT UPPER LEVEL POLEWARD OUTFLOW AND LOW (05-10KT) VWS. GLOBAL MODELS ARE IN GENERAL AGREEMENT THAT 99P WILL GRADUALLY DEVELOP AND TRACK SOUTHEASTWARD INTO A TROPICAL CYCLONE OVER THE NEXT 12 TO 24 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 27 TO 32 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1001 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS HIGH.

GLOBAL MODELS ARE IN GENERAL AGREEMENT THAT 99P WILL GRADUALLY DEVELOP AND TRACK SOUTHEASTWARD INTO A TROPICAL CYCLONE OVER THE NEXT 12 TO 24 HOURS.