190300Z POSITION NEAR 19.9S 39.8E.
TROPICAL CYCLONE 15S (GUITO), LOCATED APPROXIMATELY 400 NM WEST OF
ANTANANARIVO, MADAGASCAR, HAS TRACKED SOUTHWARD AT 07 KNOTS OVER THE
PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY SHOWS CONTINUED
CONSOLIDATION AS THE LOW LEVEL CIRCULATION CENTER (LLCC) HAS BECOME
TIGHTER WRAPPED WHILE THE FORMATIVE CONVECTIVE BANDS HAVE REMAINED
BROKEN. AN 182227Z AMSU-B MICROWAVE IMAGE REVEALS THE SYSTEM HAS
REMAINED FAIRLY BROAD WHILE THE BANDING HAS BECOME SLIGHTLY MORE
DEFINED. THE INITIAL POSITION IS BASED ON THE IR ANIMATION ALONG
WITH THE MICROWAVE IMAGE WITH FAIR CONFIDENCE. THE INITIAL INTENSITY
OF 45 KNOTS IS BASED ON AN 182120Z SCATTEROMETER PASS SHOWING 35 TO
45 KNOT WINDS ALONG WITH DVORAK INTENSITY ESTIMATES OF THE SAME
VALUE FROM KNES AND FMEE. UPPER LEVEL ANALYSIS INDICATES THE SYSTEM
IS UNDER A RIDGE AXIS IN AN AREA OF LOW (05-10 KNOTS) VERTICAL WIND
SHEAR (VWS) WHILE ANIMATED WATER VAPOR IMAGERY ADDITIONALLY SHOWS
GOOD POLEWARD AND EQUATORWARD OUTFLOW. THE SYSTEM IS TRACKING ALONG
THE WESTERN PERIPHERY OF A LOW- TO MID-LAYERED SUBTROPICAL RIDGE TO
THE EAST. AFTER TAU 48, A MID-LATITUDE TROUGH APPROACHING FROM THE
SOUTHWEST IS EXPECTED TO WEAKEN THE RIDGE AND CAUSE TC 15S TO
RECURVE SOUTHEASTWARD. THE SYSTEM IS EXPECTED TO INTENSIFY TO PEAK
OF 70 KNOTS DUE TO FAVORABLE UPPER-LEVELS AND WARM SEA SURFACE
TEMPERATURES(SSTS). AFTER TAU 48, INCREASING VWS ALONG WITH
DECREASING SSTS WILL BEGIN A SLOW WEAKENING PROCESS. EXTRA-TROPICAL
TRANSITION (ETT) IS FORECAST TO BEGIN BY TAU 72 AND WILL COMPLETE BY
TAU 120 AS THE SYSTEM BECOMES EMBEDDED WITHIN THE MID-LATITUDE
WESTERLIES. THE AVAILABLE NUMERIC GUIDANCE IS IN GOOD AGREEMENT WITH
THE FORECAST TRACK, LENDING TO HIGH CONFIDENCE TO THE JTWC TRACK
FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 190000Z IS 13 FEET. - JTWC
NOTE: We need to keep a close eye on this tropical storm seeing that it is moving down the Mozambique channel. Guito might just change direction and move towards the Mozambique coast. I need not spell out that if Guito change direction towards the coast that it will result in heavy rain and flooding. Even if Guito does not move towards the coast the outer bands of the storm might still bring heavy rain along the Mozambique coast. Keep a steady eye on this storm for any changes! - MSBWX
