B. TROPICAL DISTURBANCE SUMMARY:
(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 12.7S
165.3W, IS NOW LOCATED NEAR 13.2S 165.3W, APPROXIMATELY 319 NM EAST-
NORTHEAST OF PAGO PAGO, AMERICAN SAMOA. ANIMATED INFRARED SATELLITE
IMAGERY DEPICTS BETTER CONSOLIDATED DEEP CONVECTION. A 140109Z 19GHZ
AMSU PASS DEPICTS DEEP CURVED BANDING WRAPPING INTO THE LEVEL
CIRCULATION CENTER (LLCC) FROM THE NORTHERN PERIPHERY. A 132050Z
ASCAT PASS SHOWS A WELL-DEFINED LLCC WITH 20 TO 25 KNOT WINDS
WRAPPING AROUND THE CENTER AND ISOLATED 30 KNOT WINDS WITHIN THE
CONVECTION TO THE NORTHEAST. UPPER LEVEL ANALYSIS INDICATES A
FAVORABLE ENVIRONMENT WITH MODERATE (15-20 KNOT) VERTICAL WIND SHEAR
OFFSET BY STRONG DIVERGENT OUTFLOW. IN ADDITION, SEA SURFACE
TEMPERATURES ARE NEAR 30 CELSIUS. GLOBAL MODELS SHOW SIGNIFICANT
DEVELOPMENT AS IT TRACKS TO THE SOUTH. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1001 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS MEDIUM.
FMS 18Z已升格熱帶低壓，00Z預測36小時內命名
TROPICAL DISTURBANCE ADVISORY NUMBER A3 ISSUED FROM RSMC NADI
Jan 140153 UTC.
TROPICAL DEPRESSION 08F CENTRE 999HPA WAS LOCATED NEAR 13.2S 165.3W
AT 140000 UTC. POSITION POOR BASED ON HR GOES IR IMAGERY. DEPRESSION
SLOW MOVING. MAXIMUM 10 MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 25 KNOTS.
DEEP CONVECTION REMAINS PERSISTENT BUT DETACHED FROM SUPPOSED LLCC.
ORGANISATION HAS IMPROVED PAST 24 HOURS. OUTFLOW GOOD TO THE SOUTH
AND EAST. SST AROUND 30 DEGREES CELCIUS. SYSTEM LIES UNDER A MODERATE
UPPER DIVERGENCE REGION IN A LOW TO MODERATE SHEARED ENVIRONMENT.
DVORAK ANALYSIS BASED ON 0.25 WRAP YEILDS DT=1.5, MET AND PT AGREE.
FT BASED ON DT. THUS YIELDING T1.5/1.5/D0.5/24HRS.
GLOBAL MODELS HAVE PICKED UP THE SYSTEM AND SLOWLY MOVE IT
SOUTH-SOUTHEASTWARD WITH FURTHER INTENSIFICATION.
POTENTIAL FOR THIS SYSTEM TO DEVELOP INTO A TROPICAL CYCLONE IN THE
NEXT 24 TO 48 HOURS IS MODERATE TO HIGH.
FORECASTS :
AT 12 HRS VALID AT 141200 UTC 14.0S 164.4W MOV SE AT 06KT WITH 30 KT
CLOSE TO CENTRE
AT 24 HRS VALID AT 150000 UTC 15.2S 164.4W MOV SSE AT 05KT WITH 30 KT
CLOSE TO CENTRE
OUTLOOK
AT 36 HRS VALID AT 151200 UTC 16.1S 163.9W MOV SSE AT 05KT WITH 35 KT
CLOSE TO CENTRE
AT 48 HRS VALID AT 160000 UTC 17.1S 163.3W MOV SSE AT 05KT WITH 40 KT
CLOSE TO CENTRE
THE NEXT TROPICAL DISTURBANCE ADVISORY ON TD08F WILL BE ISSUED AROUND
140800 UTC.
