TROPICAL DISTURBANCE ADVISORY NUMBER A38 ISSUED FROM RSMC NADI
Jan 081347 UTC.
SEVERE TROPICAL CYCLONE ULA CENTRE 975HPA CATERGORY 3 WAS LOCATED
NEAR 18.5S 174.0E AT 081200 UTC. POSITION FAIR BASED ON HR MTSAT IR
IMAGERY. CYCLONE MOVING NORTHWEST AT ABOUT 02 KNOTS. EXPECT SUSTAINED
WINDS OF 65 KNOTS CLOSE TO THE CENTRE.
EXPECT WINDS OVER 63 KNOTS WITHIN 15 NAUTICAL MILES OF CENTRE,
OVER 47 KNOTS WITHIN 30 NAUTICAL MILES OF CENTRE,
OVER 33 KNOTS WITHIN 90 NAUTICAL MILES OF CENTRE.
DEEP CONVECTION HAS INCREASED WITH PRIMARY BANDS WRAPPING AROUND
LLCC. EYE VISIBLE IN IR IMAGERY IN PAST 5 HOURS. ORGANISATION REMAINS
GOOD. OUTFLOW GOOD. SST AROUND 28 DEGREES. SYSTEM LIES UNDER AN UPPER
RIDGE IN A LOW TO MODERATE SHEARED ENVIRONMENT. SYSTEM IS TRACKING
NORTHWEST DUE TO THE SUB-TROPICAL RIDGE LOCATED TO THE SOUTH. DVORAK
ANALYSIS BASED ON EYE PATTERN WITH 0W EYE IN LG SURROUND YIELDS
DT=4.5, MET AND PT AGREE. FT BASED ON DT. THUS YIELDING
T4.5/4.5/D1.5/24HRS.
FORECASTS :
AT 12 HRS VALID AT 090000 UTC 18.7S 173.3E MOV WSW AT 03KT WITH 65 KT
CLOSE TO CENTRE
AT 24 HRS VALID AT 091200 UTC 19.1S 172.4E MOV WSW AT 04KT WITH 65 KT
CLOSE TO CENTRE
OUTLOOK :
AT 36 HRS VALID AT 100000 UTC 19.8S 171.4E MOV WSW AT 05KT WITH 60 KT
CLOSE TO CENTRE
AT 48 HRS VALID AT 101200 UTC 20.9S 170.6E MOV lSW AT 05KT WITH 55 KT
CLOSE TO CENTRE
THE NEXT TROPICAL DISTURBANCE ADVISORY ON ULA WILL BE ISSUED AT OR
AROUND 082000 UTC.
TROPICAL DISTURBANCE ADVISORY NUMBER A41 ISSUED FROM RSMC NADI
Jan 090724 UTC.
SEVERE TROPICAL CYCLONE ULA CENTRE 965HPA CATEGORY 3 WAS LOCATED NEAR
18.7S 172.9E AT 090600 UTC. POSITION GOOD BASED ON HR MTSAT IR
IMAGERY. CYCLONE MOVING WEST-SOUTHWEST AT ABOUT 03 KNOTS. EXPECT
SUSTAINED WINDS OF 80 KNOTS CLOSE TO THE CENTRE.
EXPECT WINDS OVER 63 KNOTS WITHIN 15 NAUTICAL MILES OF CENTRE,
OVER 47 KNOTS WITHIN 30 NAUTICAL MILES OF CENTRE,
AND OVER 33 KNOTS WITHIN 80 NAUTICAL MILES OF CENTRE.
EYE WELL DEFINED IN PAST 6 HOURS WITH CLOUD TOPS COOLING. DEEP
CONVECTION HAS INCREASED WITH CLOUD TOPS COOLING PAST 3 HOURS.
ORGANISATION REMAINS GOOD. OUTFLOW GOOD. SST AROUND 27 TO 28 DEGREES.
SYSTEM LIES UNDER A STRONG UPPER DIVERGENCE REGION IN A LOW TO
MODERATE SHEARED ENVIRONMENT. SYSTEM IS TRACKING WEST-SOUTHWEST DUE
TO THE SUB-TROPICAL RIDGE LOCATED TO THE SOUTHEAST. DVORAK ANALYSIS
BASED ON EYE PATTERN WITH OW EYE IN LG SURROUND YIELDS DT=5.0, MET
AND PT AGREE. FT BASED ON DT. THUS YIELDING T5.0/5.0/D1.5/24HRS.
