02W(MAWAR) accelerating and completing ETT//Invest 98W// TD 02L over the Gulf of Mexico// 0209utc

JTWC IS ISSUING 6HOURLY WARNINGS AND 3HOURLY SATELLITE BULLETINS ON TS 02W(MAWAR).

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS CONVECTION CONFINED TO THE EASTERN PORTIONS OF A BROAD CIRCULATION DUE TO UPPER-LEVEL TROUGHING OVER THE WESTERN PORTION OF THE CIRCULATION AND DIVERGENT FLOW TO THE EAST. THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED ON SUBJECTIVE AGENCY FIXES AND 020421Z 37 GHZ GPM MICROWAVE IMAGER DATA. THE INITIAL INTENSITY OF 45 KTS IS ASSESSED WITH HIGH CONFIDENCE BASED ON RECENT CIMSS SATELLITE CONSENSUS ESTIMATES AND PERIPHERAL WINDS EXCEEDING 40 KNOTS EVIDENT IN BOTH EARLIER ASCAT DATA AND IN WIND SPEEDS DERIVED FROM A 020346Z AMSR2 PASS.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THE CURRENT FORECAST TRACK IS SITUATED ABOUT 35 NM NORTH OF THE PREVIOUS FORECAST TRACK AT TAU 12 AND 30 NM NORTH AT TAU 24 DUE TO RECENT STORM MOTION, BUT CONVERGES WITH THE PREVIOUS FORECAST TRACK THEREAFTER. OTHERWISE, THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TS 02W WILL ACCELERATE EAST-NORTHEASTWARD AND COMPLETE EXTRATROPICAL TRANSITION DURING THE FORECAST PERIOD. UPPER-LEVEL FLOW ASSOCIATED WITH THE BAROCLINIC ZONE TO THE NORTH REMAINS FAIRLY ZONAL, AND THE SYSTEM IS EXPECTED TO STAY FULLY TROPICAL FOR AT LEAST THE NEXT 12 HOURS AS IT ACCELERATES EAST-NORTHEASTWARD IN THE STRONG STEERING FLOW ASSOCIATED WITH THE STR TO THE EAST AND SOUTH. HOWEVER, BY TAU 24, A LOW AMPLITUDE MIDLATITUDE TROUGH WILL BEGIN TO INTERACT WITH THE SYSTEM, AND 02W WILL TRANSITION TO A GALE FORCE EXTRATROPICAL LOW BY TAU 36. STRONG POLEWARD AND EASTWARD OUTFLOW ALOFT FOLLOWED BY FAVORABLE INTERACTION WITH THE AFOREMENTIONED MIDLATITUDE TROUGH DURING EXTRATROPICAL TRANSITION WILL ALLOW THE SYSTEM TO MAINTAIN INTENSITY THROUGHOUT THE FORECAST PERIOD DESPITE DECREASING ALONG-TRACK SEA SURFACE TEMPERATURES AND INCREASING VERTICAL WIND SHEAR. THE DEEPEST CONVECTION AND STRONGEST LOW-LEVEL WINDS ASSOCIATED WITH THE SYSTEM ARE EXPECTED TO REMAIN WITHIN THE EASTERN AND SOUTHERN QUADRANTS.

MODEL DISCUSSION: NUMERICAL MODEL GUIDANCE IS IN VERY GOOD AGREEMENT REGARDING THE DIRECTION OF MOTION AND THE OVERALL FORECAST SCENARIO, WITH SOME SPREAD IN THE ALONG-TRACK DIRECTION AS MIGHT BE EXPECTED FOR AN ACCELERATING SYSTEM. NUMERICAL MODELS ARE IN EXCELLENT AGREEMENT WITH THE INTENSITY FORECAST, WHICH IS SET WITH HIGH CONFIDENCE.

AN AREA OF CONVECTION (INVEST 98W) HAS PERSISTED NEAR 8.5N 142.1E, APPROXIMATELY 330 NM SOUTH-SOUTHWEST OF GUAM. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A FULLY-EXPOSED LLCC AS EVIDENCED BY A 020032Z ASCAT METOP-C BULLSEYE PASS. CONSOLIDATION OF THE LOW-LEVEL CIRCULATION IS ALSO EVIDENT IN RECENT TOTAL PRECIPITABLE WATER ANIMATION. THUS FAR, CONVECTIVE DEVELOPMENT ASSOCIATED WITH THE DISTURBANCE HAS BEEN MINIMAL. UPPER-LEVEL ANALYSIS INDICATES 98W IS IN A FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH LOW TO MODERATE (5-10 KNOT) VWS, WARM (29-30C) SEA SURFACE TEMPERATURES, AND MODERATE DIVERGENCE ALOFT. GLOBAL DETERMINISTIC AND ENSEMBLE MODELS GENERALLY AGREE THAT THE SYSTEM WILL DEVELOP INTO A TROPICAL DEPRESSION OVER THE NEXT FEW DAYS, ALTHOUGH THERE IS SOME UNCERTAINTY REGARDING THE TIMELINE AND LOCATION OF FORMATION. HOWEVER, IT APPEARS LIKELY THAT THE CENTER OF THE CIRCULATION WILL PASS TO THE WEST OF GUAM, BUT THE EASTERN INFLOW REGION WITH ASSOCIATED HIGHER WINDS AND CONVECTIVE DEVELOPMENT COULD AFFECT GUAM AND THE CNMI IN ABOUT 48 TO 72 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 10 TO 15 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1009 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS LOW.