040900Z POSITION NEAR 9.0N 83.1E.
TROPICAL CYCLONE 01B (ONE), LOCATED APPROXIMATELY 300 NM SOUTHEAST
OF CHENNAI, INDIA, HAS TRACKED WEST-NORTHWESTWARD AT 06 KNOTS OVER
THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS
A TIGHTLY WRAPPED, ALBEIT PARTIALLY-EXPOSED, LOW-LEVEL CIRCULATION
CENTER (LLCC) WITH FLARING DEEP CONVECTION LOCATED ACROSS THE
WESTERN SEMI-CIRCLE. A 040434Z AMSU-B MICROWAVE IMAGE REVEALS A
TIGHTLY WRAPPED SYSTEM WITH DEEP CONVECTION SHEARED OFF TO THE WEST.
A 030340Z ASCAT PASS DEPICTS A DEFINED CIRCULATION WITH 25 TO 30
KNOT WINDS WRAPPED COMPLETELY AROUND WITH SOME 30 TO 40 KNOT WINDS
LOCATED IN THE NORTHWESTERN QUADRANT. THE INITIAL POSITION IS BASED
UPON THE EXPOSED LLCC SEEN IN THE MSI WITH GOOD CONFIDENCE. THE
INITIAL INTENSITY OF 35 KNOTS IS BASED UPON THE ASCAT PASS WHILE
DVORAK INTENSITY FROM PGTW AND KNES INDICATE 30 KNOTS WHICH IS
MOSTLY DUE TO THE SHEARED NATURE OF THE SYSTEM. UPPER-LEVEL ANALYSIS
INDICATES TC 01B IS LOCATED IN A MARGINAL ENVIRONMENT AS MODERATE
(15 TO 20 KNOTS) VERTICAL WIND SHEAR (VWS) IS OFFSETTING OVERALL
FAVORABLE DIVERGENT OUTFLOW. TC 01B IS TRACKING GENERALLY WEST ALONG
THE SOUTHERN PERIPHERY OF A DOMINATE SUBTROPICAL RIDGE (STR) LOCATED
TO THE NORTH OF THE SYSTEM. THIS STR WILL REMAIN THE STEERING
INFLUENCE FOR THE SYSTEM THROUGH THE REMAINDER OF THE FORECAST
PERIOD AS IT SLOWLY TRACKS THE SYSTEM TO THE WEST. TC 01B WILL
STRUGGLE TO MAINTAIN TROPICAL CYCLONE STRENGTH AS IT PROCEEDS WEST
DUE TO THE MODERATE VWS AND A POSSIBILITY OF DRY AIR ENTRAINMENT
FROM CONTINENTAL INDIA. THE SYSTEM IS EXPECTED TO DISSIPATE BELOW
WARNING THRESHOLD BY TAU 48 AS IT MAKES LANDFALL ACROSS NORTHERN SRI
LANKA, ALTHOUGH THERE IS A DISTINCT POSSIBILITY THAT THE SYSTEM MAY
DISSIPATE BEFORE THEN DUE TO THE AFOREMENTIONED ENVIRONMENTAL
CONDITIONS. AVAILABLE DYNAMIC MODEL GUIDANCE IS SLIGHTLY SPREAD BUT
OVERALL AGREES WITH A SLOW, GENERALLY WESTWARD TRACK. NAVGEM IS THE
SOLE OUTLIER AS IT SEVERELY WEAKENS THE VORTEX AND BECOMES ERRATIC
DRIVING THE SYSTEM TO THE SOUTH. DUE TO THIS SPREAD, THE OFFICIAL
JTWC FORECAST TRACK IS POSITIONED SLIGHTLY FASTER THAN MULTI-MODEL
CONSENSUS TO OFFSET THE NAVGEM SOLUTION WITH LOW CONFIDENCE. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 040600Z IS 10 FEET. NEXT WARNINGS AT
041500Z, 042100Z, 050300Z AND 050900Z. THIS WARNING SUPERSEDES AND
CANCELS REF A, JOINT TYPHOON WRNCEN PEARL HARBOR HI 040251Z JAN 14
TROPICAL CYCLONE FORMATION ALERT (WT
