JTWC: busy cyclonic monitoring, STY 19W(CHANTHU) peaked as a CAT 5(155knots) with gusts well over 300km/h, 11/03utc updates

JTWC ARE ISSUING 6HOURLY WARNINGS AND 3HOURLY SATELLITE BULLETINS ON 18W AND 19W. A TROPICAL CYCLONE FORMATION ALERT WAS ISSUED FOR 96W AT 10/17UTC AND HAS BEEN CANCELLED AT 11/07UTC. 95B IS NOW A ON THE MAP(10/18UTC) AS MEDIUM.

STY 19W(CHANTHU) PEAKED AT 10/18UTC AS A CAT 5 WITH MAXIMUM SUSTAINED WINDS ESTIMATED AT 290KM/H GUSTING WELL OVER 300KM/H.

TS 18W(CONSON). WARNING 21 ISSUED AT 11/03UTC.SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TS CONSON WILL TRACK WESTWARD TO WEST- NORTHWESTWARD THROUGH THE FORECAST PERIOD UNDER THE STEERING INFLUENCE OF THE SUBTROPICAL RIDGE. THE SYSTEM SHOULD MAKE LANDFALL OVER DA NANG,VIETNAM NEAR 24H WITH RAPID WEAKENING AS THE SYSTEM TRACKS INLAND OVER THE MOUNTAINOUS TERRAIN. TS 18W IS EXPECTED TO DISSIPATE BY 72H.

TS 18W(CONSON). SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS AN EXPANDING CENTRAL COLD COVER (CCC) OBSCURING THE LOW-LEVEL CIRCULATION CENTER (LLCC). RECENT VISIBLE IMAGERY INDICATES THE LLCC IS POSITIONED ALONG THE EASTERN EDGE OF THIS AREA OF INTENSE CONVECTION. A 102314Z SSMIS 37GHZ IMAGE REVEALS IMPROVED CONVECTIVE ORGANIZATION WITH CONVECTIVE BANDING WRAPPING INTO A DEFINED LLCC, WHICH SUPPORTS THE INITIAL POSITION WITH MEDIUM CONFIDENCE. THE INITIAL INTENSITY OF 50 KNOTS IS ASSESSED WITH MEDIUM CONFIDENCE AND IS HEDGED ABOVE THE PGTW DVORAK ESTIMATE, WHICH IS BASED ON THE DVORAK CCC METHOD. UPPER-LEVEL ANALYSIS INDICATES A MARGINALLY-FAVORABLE ENVIRONMENT WITH MODERATE EASTERLY VERTICAL WIND SHEAR OFFSET BY MODERATE WESTWARD OUTFLOW.

TS 18W(CONSON). MODEL DISCUSSION: NUMERICAL MODEL GUIDANCE REMAINS IN TIGHT AGREEMENT THROUGH 24H BUT DIVERGES AS THE SYSTEM MOVES OVERLAND LENDING MEDIUM OVERALL CONFIDENCE IN THE FORECAST TRACK. THERE IS A SLIGHT POSSIBILITY OF FURTHER INTENSIFICATION PRIOR TO LANDFALL BUT IT IS EXPECTED TO BE MINIMAL DUE TO THE MARGINALLY FAVORABLE CONDITIONS. OVERALL, THERE IS MEDIUM CONFIDENCE IN THE JTWC INTENSITY FORECAST.

STY 19W(CHANTHU). WARNING 20 ISSUED AT 11/03UTC.

STY 19W(CHANTHA). SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: WHILE UNDERGOING AN EYEWALL REPLACEMENT CYCLE AND ABSORBING INVEST 96W, STY 19W HAS WEAKENED SIGNIFICANTLY OVER THE PAST SIX HOURS WITH THE LOSS OF THE EYE AND WARMING CLOUD TOP TEMPERATURES. ADDITIONALLY, ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A MORE ASYMMETRIC CONVECTIVE STRUCTURE, WHICH MAY SIGNAL A MORE RAPID WEAKENING TREND. OVERALL, CONFIDENCE IN THE INITIAL POSITION REMAINS HIGH. THE INITIAL INTENSITY IS ASSESSED AS MEDIUM CONFIDENCE BASED ON DVORAK ESTIMATES RANGING FROM 7.0 TO 7.5 AND THE ADT ESTIMATE. UPPER-LEVEL CONDITIONS HAVE REMAINED HIGHLY FAVORABLE WITH STRONG RADIAL OUTFLOW AND ENHANCED POLEWARD OUTFLOW.

STY 19W(CHANTHU).MODEL DISCUSSION: NUMERICAL MODEL GUIDANCE IS IN TIGHT AGREEMENT THROUGH 72H WITH A 270KM SPREAD IN SOLUTIONS AT 72H LENDING HIGH CONFIDENCE IN THE JTWC FORECAST TRACK. AFTER 72H, THERE IS INCREASING UNCERTAINTY WITH WEAKER STEERING FLOW THUS MEDIUM TRACK CONFIDENCE. OVERALL, THERE IS MEDIUM CONFIDENCE IN THE JTWC INTENSITY FORECAST DUE TO THE COMPLEX INTERACTIONS WITH THE AFOREMENTIONED TROUGH AND SUBTROPICAL WESTERLIES AS WELL AS INTERACTION WITH TAIWAN AND EASTERN CHINA.

STY 19W(CHANTHU). HWRF AT 10/18UTC. INTENSITY GUIDANCE: 150KNOTS AT +0H.

INVEST 96W. TROPICAL CYCLONE FORMATION ALERT ISSUED AT 10/17UTC UPDATE AT 11/06UTC.THE AREA OF CONVECTION (INVEST 96W) PREVIOUSLY LOCATED NEAR 22.7N 124.9E IS NOW LOCATED NEAR 22.3N 121.1E, APPROXIMATELY 395 KM SOUTHWEST OF ISHIGAKIJIMA. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) AND RECENT PARTIAL SCATTEROMETER PASSES DO NOT SHOW A SEPARATE AND DISCREET LOW LEVEL CIRCULATION (LLC) AT THIS TIME. HOWEVER, MODEL FIELDS AND SURFACE OBSERVATIONS FROM THE REGION SUGGEST THAT A WEAK LLC MAY EXIST OVER OR VERY NEAR THE EAST COAST OF TAIWAN. WHATEVER LLC IS PRESENT IS MOVING RAPIDLY SOUTHWESTWARD TOWARDS STY 19W, AS IT IS ALREADY CAPTURED BY THE OVERALL LOW LEVEL FLOW ASSOCIATED WITH STY 19W. INVEST 96W IS EXPECTED TO BE FULLY ABSORBED BY STY 19W AND DISSIPATE AS A SEPARATE LLC WITHIN THE NEXT 6 TO 12 HOURS. INVEST 96W IS UNDER THE WESTERLY OUTFLOW FROM STY 19W, HOWEVER, VERTICAL WIND SHEAR IS MODERATE (10-15 KNOTS) AND SEA SURFACE TEMPERATURES (SST) ARE VERY WARM (30-31C). GLOBAL MODELS FAIL TO EVEN PICK UP A CIRCULATION ASSOCIATED WITH 96W, BUT THE HWRF STILL SHOWS SHARP TURNING ALONG THE COAST OF TAIWAN AND INDICATES A POSSIBILITY OF THE SYSTEM REACHING 25 KNOTS DURING A VERY BRIEF WINDOW WITHIN THE NEXT 6 TO 12 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1005 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS HIGH.

11/00UTC.

EASTERN PACIFIC. TS 15E(OLAF). WARNING 14 ISSUED AT 11/04UTC.CURRENT INTENSITY IS 35KNOTS AND IS FORECAST TO FALL BELOW 25KNOTS BY 12/00UTC.

TS 15E(OLAF). GUIDANCE.

NORTH INDIAN. INVEST 95B. 10/18UTC. AN AREA OF CONVECTION (INVEST 95B) HAS PERSISTED NEAR 16.0N 88.0E, APPROXIMATELY 905 KM EAST-NORTHEAST OF CHENNAI, INDIA. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS EXPANSIVE AND SCATTERED CONVECTION AROUND A BROAD EXPOSED LOW LEVEL CIRCULATION. A 101328Z ASCAT-A IMAGE SHOWS AN ELONGATED CIRCULATION WITH A SWATH OF 25-30 KNOT CONVERGENT WESTERLY WINDS OVER THE SOUTHERN SEMICIRCLE. ENVIRONMENTAL ANALYSIS INDICATES AN OVERALL FAVORABLE ENVIRONMENT DUE TO MODERATE VERTICAL WIND SHEAR (15-20 KT), FAVORABLE SEA SURFACE TEMPERATURES (29-30C), AND BURGEONING EQUATORWARD OUTFLOW. GLOBAL MODELS ARE IN AGREEMENT THAT INVEST 95B WILL TRACK NORTHWEST AND HAS A SMALL WINDOW TO INTENSIFY WILL THE TROPICAL EASTERLY JET WEAKENING IN THE NORTHERN BAY OF BENGAL. MAXIMUM SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 999 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS MEDIUM.

11/00UTC.

ATLANTIC. HU 12L(LARRY). WARNING 42 ISSUED AT 11/03UTC. CURRENT INTENSITY IS 70KNOTS/CAT1 AND IS FORECAST TO FALL BELOW 65KNOTS BY 12/00UTC.

HU 12L(LARRY). GUIDANCE.