Current Southern Hemisphere Tropical Systems: Tropical Cyclone 16S (Sixteen)

190300Z POSITION NEAR 20.2S 41.3E.
TROPICAL CYCLONE (TC) 16S, LOCATED APPROXIMATELY 335 NM WEST OF 
ANTANANARIVO, MADAGASCAR, HAS TRACKED SOUTHEASTWARD AT 03 KNOTS OVER 
THE PAST SIX HOURS. ANIMATED INFRARED (IR) SATELLITE IMAGERY DEPICTS 
DEEP CONVECTIVE BANDING WRAPPING ALONG THE NORTHERN AND EASTERN 
PERIPHERIES OF A CONSOLIDATING LOW LEVEL CIRCULATION CENTER (LLCC). 
A MOSAIC OF RECENT MICROWAVE SATELLITE IMAGERY REVEALS THAT THE 
CONVECTIVE ORGANIZATION HAS STEADILY IMPROVED OVER THE PAST 24 
HOURS. THE INITIAL POSITION IS BASED ON THE ANIMATED IR LOOP AND A 
182254Z AMSU 89GHZ MICROWAVE IMAGE. THE INITIAL INTENSITY IS 
ASSESSED AT 35 KNOTS BASED ON THE PGTW DVORAK INTENSITY ESTIMATE. 
UPPER LEVEL ANALYSIS INDICATES TC 16S IS LOCATED JUST SOUTH OF A 
RIDGE AXIS, WITH A POINT SOURCE OVERHEAD PROVIDING GOOD RADIAL 
OUTFLOW. THE SYSTEM IS CURRENTLY UNDER MODERATE (15-20 KNOT) 
VERTICAL WIND SHEAR (VWS). TC 16S IS CURRENTLY TRACKING SLOWLY 
SOUTHEASTWARD UNDER THE INFLUENCE OF LOW- TO MID-LEVEL SUB-TROPICAL 
RIDGING TO THE NORTHEAST. A DEEP-LAYER MID-LATITUDE TROUGH IS 
EXPECTED TO MOVE IN FROM THE WEST AFTER TAU 48, ADDING ADDITIONAL 
VWS AND AMPLIFYING THE DEEP LAYER RIDGE TO THE EAST. THIS WILL 
ACCELERATE THE SOUTHEASTERLY MOTION. THE FORECAST IS IN GOOD 
AGREEMENT WITH THE ECMWF AND GFS MODELS, WHICH TRACK THE SYSTEM OVER 
SOUTHERN MADAGASCAR, WHILE THE NOGAPS AND GFDN MODELS KEEP THE 
SYSTEM UNREASONABLY STATIONARY DESPITE THE PASSING TROUGH. THIS 
WARNING SUPERSEDES AND CANCELS REF A, JOINT TYPHOON WRNCEN PEARL 
HARBOR HI 180121Z FEB 13 TROPICAL CYCLONE FORMATION ALERT (WTXS21 
PGTW 180130). MAXIMUM SIGNIFICANT WAVE HEIGHT AT 190000Z IS 12 FEET. 

- JTWC + Eumetsat