TC 08S(CHENESO) forecast to reach Typhoon intensity by 36h over the warm MOZ Channel//2403utc

JTWC IS ISSUING 12HOURLY WARNINGS AND 3HOURLY SATELLITE BULLETINS ON TC 08S(CHENESO).

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED SATELLITE IMAGERY AND A 232257Z GMI SERIES VERIFY THAT TROPICAL STORM CHENESO HAS MOVED INTO THE MOZAMBIQUE CHANNEL AND RE-INTENSIFIED. THE JTWC DVORAK ASSESSMENT IS T2.5 AND THE LOW FREQUENCY MICROWAVE IMAGERY SHOWS WELL ORGANIZED BANDING WRAPPING AROUND A CLEAR LOW LEVEL CIRCULATION CENTER WHILE THE UPPER FREQUENCIES CONFIRM AN INCREASE IN DEEP CONVECTION. THE SYSTEM EXISTS IN A NEARLY IDEAL ENVIRONMENT WITH LOW VERTICAL WIND SHEAR, SATURATION THROUGHOUT THE COLUMN, AND 29-30 DEGREE SEAWATER. ANIMATED WATER VAPOR IMAGERY SHOWS VIGOROUS EQUATORWARD OUTFLOW AS WELL AS A DEVELOPING POLEWARD OUTFLOW CHANNEL. THERE IS SOME SUBSIDENCE DISPLACED FAR TO THE SOUTHWEST BUT IT DOES NOT APPEAR TO BE AFFECTING THE STORM AT THIS POINT. TC 09S IS WEDGED BETWEEN THE NEAR EQUATORIAL RIDGE, WHICH IS ANCHORED IN AN ANTICYCLONE NEAR 10S 58E, AND THE SUBTROPICAL RIDGE, WHICH EXTENDS ALONG THE 30TH LATITUDE. UNTIL THOSE RIDGES WEAKEN OR SHIFT THE SYSTEM HAS NOWHERE TO GO AND WILL MEANDER OVER THE CHANNEL. THUS, UPWELLING WILL HAVE A MAJOR INFLUENCE ON SYSTEM INTENSITY.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THIS IS THE FIRST PROGNOSTIC REASONING MESSAGE FOLLOWING THE RESUMPTION OF WARNINGS AND RE-ESTABLISHES THE FORECAST PHILOSOPHY. FORECAST DISCUSSION: TC 08S WILL CHURN OVER THE CHANNEL FOR THE NEXT 48 HOURS THEN BEGIN A POLEWARD TRACK TO THE SOUTHWEST AS THE SUBTROPICAL RIDGE WEAKENS AND TRACKS DOWNSTREAM. ALTHOUGH THE SYSTEM WILL REMAIN IN A NEARLY IDEAL ENVIRONMENT FOR THE FIRST 48 HOURS THE SLOW STORM MOTION WILL GENERATE UPWELLING THAT WILL BE AN IMPEDIMENT TO EXPLOSIVE DEVELOPMENT. PEAK INTENSITY WILL OCCUR NEAR TAU 96 AS THE SYSTEM APPROACHES THE 24TH LATITUDE AND BEGINS A BEND TO THE SOUTHEAST. ENHANCED POLEWARD OUTLOW WILL INITIALLY GIVE THE SYSTEM A BOOST AS IT INTERACTS WITH THE MID-LATITUDE WESTERLIES. ONCE THE SYSTEM MAKES THE TURN, HOWEVER, IT WILL ENCOUNTER INCREASING SHEAR AS IT BEGINS THE EXTRA-TROPICAL TRANSITION PROCESS.

MODEL DISCUSSION: MODEL GUIDANCE HAS BEEN QUALITATIVELY ACCURATE IN CAPTURING THE SCENARIO BUT IS A STEP BEHIND ON CAPTURING HOW QUICKLY THE SYSTEM WOULD REGENERATE. TRACK GUIDANCE IS WIDELY SPREAD BUT THE CONSENSUS SHOWS THE BEGINNING OF THE TURN OCCURRING PAST 23S AND COMPLETING BEFORE 25S. INTENSITY GUIDANCE HAS BEEN LAGGING BUT THE LATEST RUN INDICATES IT IS CATCHING UP. STATISTICAL-DYNAMIC GUIDANCE IS IN GOOD ALIGNMENT WITH CONSENSUS. BOTH AGREE ON A PEAK IN INTENSITY BETWEEN 70 AND 80 KNOTS NEAR TAU 96. THE JTWC FORECAST STAYS CLOSE TO THE MULTI-MODEL CONSENSUS IN BOTH TRACK AND INTENSITY.