TC 01W RAPIDLY DEVELOP OVER SOUTH CHINA SEA THREATHENS SOUTHERN VIETNAM AND CAMBODIA

AS OF 2P PHIL TIME JAN 19 2010

TROPICAL CYCLONE 01W

STRONG DEPRESSION STAGE (LEVEL 3/15)

CURRENT INTENSITY: MAX: 30kt GUST: 40kt (56-74kph)
CURRENT PRESSURE: 1000MB
SURFACE WIND ANALYSIS: 34KT (63KPH) MSLP: 1007.3MB
ADVANCE DVORAK TECHNIQUES (ADT): 31KT (57KPH) MSLP: 999.4MB
CENTRAL REGION TEMP: +1.7C (CENTER)
CENTRAL CLOUD TEMP: -13.6C (+25MM/HR)
FORECAST 12HRS: 35KT/65KPH/LEVEL 4

DISCUSSION:

12 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION (TD) 01W (ONE) HAS DEVELOPED IN THE SOUTH CHINA SEA (SCS) UNDER THE INFLUENCE OF A STRONG NORTHEASTERLY FLOW ACROSS THE SCS AND A WESTERLY WIND BURST NEAR THE EQUATOR THAT HAS STARTED TO WRAP INTO THE SOUTHERN HALF OF TD 01W. OVER THE PAST 12 HOURS THE CONVECTION AROUND THE WELL DEFINED LOW LEVEL CIRCULATION CENTER (LLCC) HAS BEEN SHEARED TO THE NORTHWEST, AS THE LLCC PROGRESSES MORE SLOWLY TO THE WEST-NORTHWEST. THE INTENSITY HAS REMAINED FAIRLY CONSISTENT AT 30 KNOTS OVER THE PAST SIX HOURS AND IS BASED ON THE PGTW 2.5 DVORAK FIX. EVEN WITH THE SHEARING OF CONVECTION OBSERVED IN THE ENHANCED INFRARED SATELLITE LOOP, THE LLCC HAS BEEN ABLE TO MAINTAIN ITS STRUCTURE OVER THE PAST SIX HOURS, AND CONVECTION (ALTHOUGH NOT DEEP) HAS BEEN PERSISTENT IN THE VICINITY OF THE LLCC.
THE TRACK FOR TD 01W IS BEING INFLUENCED BY A LOW- TO MID-LEVEL SUBTROPICAL RIDGE (STR) AXIS TO THE NORTHEAST OF TD 01W. SURFACE CONDITIONS REMAIN FAVORABLE WITH FAVORABLE SEA SURFACE TEMPERATURES THROUGHOUT THE SCS, HOWEVER THE UPPER LEVEL ENVIRONMENT HAS STARTED TO SEE INCREASED VERTICAL WIND SHEAR (VWS) DEVELOPING OVER THE LLCC

FORECAST REASONING
A. THIS PROGNOSTIC REASONING BULLETIN ESTABLISHES THE FORECAST PHILOSOPHY.
B. TS 01W WILL CONTINUE TO TRACK WEST-NORTHWEST UNDER THE INFLUENCE OF THE STR THROUGH TAU 36. THE LLCC WILL HAVE ONLY A BRIEF PERIOD OF INTENSIFICATION AS OUTFLOW NEAR THE COAST OF VIETNAM IS EXPECTED TO INCREASE AS VWS INCREASES. HOWEVER, THE VWS ALONG WITH LAND INTERACTION WILL QUICKLY CAUSE THE LLCC TO DISSIPATE OVER SOUTHERN VIETNAM AND CAMBODIA BY TAU 36. MODEL GUIDANCE IS IN GOOD AGREEMENT WITH THE CURRENT FORECAST.

JUST VOTE OR COMMENT FOR FEEDBACK