15UTC: TC LORNA(25S) forecast to intensify to category 1 US in 36hours with some interaction with developing 92S possible in 72h


Warning 5/JTWC


TC LORNA (25S)
As of 12:00 UTC Apr 24, 2019:

Location: 10.7°S 84.5°E
Maximum Winds: 40 kt ( 75km/h)
Gusts: 50 kt ( 95km/h)

Minimum Central Pressure: 981mb
REMARKS:
241500Z POSITION NEAR 10.9S 84.6E.
TROPICAL CYCLONE (TC) 25S (LORNA), LOCATED APPROXIMATELY 743 NM EAST-
SOUTHEAST OF DIEGO GARCIA, HAS TRACKED EAST-SOUTHEASTWARD AT 06
KNOTS (KTS) OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY REVEALS PERSISTENT DEEP CONVECTION TO THE WEST OF,
AND OBSCURING, THE LOW LEVEL CIRCULATION CENTER (LLCC). THE INITIAL
POSITION IS PLACED WITH FAIR CONFIDENCE BY FOLLOWING LOW LEVEL RAIN
BANDS AND THE CURVATURE OF THE DEEP CONVECTION IN A 241128Z SSMIS 89
GHZ MICROWAVE IMAGE. THE INITIAL INTENSITY OF 40 KTS IS AVERAGED
BETWEEN PGTW, FMEE, AND KNES DVORAK FIXES OF T2.5-T3.0 (35-45 KTS).
THE ENVIRONMENT IS MARGINALLY FAVORABLE WITH MODERATE (15-20 KT)
VERTICAL WIND SHEAR (VWS), GOOD POLEWARD OUTFLOW, AND WARM (29-30
CELSIUS) SEA SURFACE TEMPERATURE. TC 25S IS TRACKING ALONG THE
SOUTHWEST PERIPHERY OF A NEAR-EQUATORIAL RIDGE. BY TAU 72, THE TRACK
IS EXPECTED TO SHIFT AS A SUBTROPICAL RIDGE TO THE SOUTHEAST TAKES
OVER AS THE PRIMARY STEERING INFLUENCE. ADDITIONALLY, A DEVELOPING
CIRCULATION (92S) TO THE EAST IS EXPECTED TO INTERACT AND POSSIBLY
MERGE WITH TC 25S, ADDING MORE COMPLEXITY TO THE TRACK FORECAST.
REGARDING THE INTENSITY FORECAST, VWS IS EXPECTED TO BECOME MORE
FAVORABLE IN THE NEXT FEW HOURS AND STEADY INTENSIFICATION TO 75 KTS
BY TAU 72 IS EXPECTED. AFTER TAU 72, HIGH VWS IS EXPECTED TO CAUSE
TC 25S TO WEAKEN FAIRLY QUICKLY. BY TAU 120, INTERACTION WITH THE
MID-LATITUDE BAROCLINIC ZONE IS EXPECTED TO INITIATE EXTRATROPICAL
TRANSITION. ALL AVAILABLE DYNAMIC MODEL TRACKERS DEPICT A POLEWARD
TRACK BUT, DUE TO VARIATIONS IN THE TIMING AND DEGREE OF INFLUENCE
ON THE TRACK FROM THE AFOREMENTIONED STEERING INFLUENCES, THERE IS
WIDE SPREAD BETWEEN THE MODELS. GFS AND THE GFS ENSEMBLE MEAN ARE ON
THE WESTERN EDGE OF THE GUIDANCE ENVELOPE WHILE UKMET AND GALWEM ARE
ON THE EASTERN EDGE. THE REMAINING MEMBERS ARE TIGHTLY CLUSTERED
NEAR THE JTWC TRACK FORECAST. BASED ON THE MODEL SOLUTIONS HAVING
OVER 700 NM OF SPREAD BY TAU 120 AND THE COMPLEX STEERING
ENVIRONMENT, THERE IS LOW CONFIDENCE IN THE JTWC TRACK FORECAST.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 241200Z IS 16 FEET. NEXT WARNINGS
AT 242100Z, 250300Z, 250900Z AND 251500Z. REFER TO TROPICAL CYCLONE
24S (KENNETH) WARNINGS (WTXS31 PGTW) FOR SIX-HOURLY UPDATES.//
NNNN

WARNING 5/JTWC
WARNING 5/JTWC

1316UTC
1316UTC





Rédigé par PATRICK HOAREAU le Mercredi 24 Avril 2019 à 21:34