SPAC: MAL - Post-Tropical

[Subtrop]

91P INVEST 231106 1200 5.0S 170.0E SHEM 15 1006

[ElectricStorm]

02P TWO 231113 0000 9.6S 170.6E SHEM 35 996

First JTWC forecast has a 55kt peak

[cycloneye]

FORECAST DISCUSSION: TROPICAL CYCLONE (TC) 02W (MAL) WILL TRACK
SOUTHEASTWARD ALONG THE WESTERN SIDE OF THE STEERING RIDGE THROUGH
THE ENTIRETY OF THE FORECAST PERIOD. SOME SLIGHT DEVIATIONS EAST OR
WEST OF THE FORECAST TRACK ARE POSSIBLE AS THE RIDGE EXPANDS OR
RETREATS AT THE MESOSCALE LEVEL, BUT OVERALL THE TRACK FORECAST IS
STRAIGHT FORWARD. THE SYSTEM IS EXPECTED TO PASS ABOUT 60NM WEST OF
NADI, FIJI BY TAU 24, THEN MOVE INTO THE OPEN WATERS OF THE SOUTH
PACIFIC THROUGH THE REMAINDER OF THE FORECAST. DUE TO A SLOW
RELAXATION OF THE STEERING GRADIENT, THE SYSTEM IS FORECAST TO SLOW
DOWN OVER THE NEXT 48 HOURS BEFORE PICKING UP A BIT MORE SPEED BY
THE END OF THE FORECAST. WHILE THE VORTEX IS STILL TILTED A BIT DUE
TO SOME PERSISTENT MID-LEVEL NORTHEASTERLY SHEAR, GLOBAL MODEL
FIELDS SUGGEST THE SHEAR WILL WEAKEN OVER THE NEXT FEW HOURS, WHICH
SHOULD ALLOW THE CONVECTION SEEN FIRING OFF NOW, TO HELP ALIGN THE
VORTEX. ONCE THIS OCCURS, THE SYSTEM WILL RAPIDLY INTENSIFY THROUGH
TAU 24, REACHING AT LEAST 75 KNOTS AS IT PASSES WEST OF NADI. THE
WINDOW OF OPPORTUNITY FOR INTENSIFICATION WILL BE FLEETING HOWEVER,
WITH SHEAR EXPECTED TO SHARPLY INCREASE BY TAU 36. BY TAU 48, THE
SYSTEM WILL BE WELL INTO COOLER WATERS, WILL BE DECAPITATED BY THE
VERY HIGH WESTERLY SHEAR AND WILL BE IN THE PROCESS OF BEING
SMOTHERED BY VERY DRY MID-LEVEL AIR. THIS WILL MARK THE BEGINNING
OF A RAPID SUBTROPICAL TRANSITION (STT), WHICH WILL BE COMPLETED NO
LATER THAN TAU 72.

MODEL DISCUSSION: DETERMINISTIC AND ENSEMBLE TRACK GUIDANCE REMAINS
IN VERY GOOD AGREEMENT OVERALL, WITH THE CONTINUED EXCEPTION OF THE
NAVGEM MODEL. DISCARDING NAVGEM, THE REMAINDER OF THE GUIDANCE
PACKAGE IS CONFINED TO AN ENVELOPE WHICH GRADUALLY EXPANDS TO JUST
125NM BY TAU 72. THE JTWC FORECAST REMAINS CONSISTENT WITH THE
PREVIOUS FORECAST AND THE CONSENSUS MEAN WITH HIGH CONFIDENCE.
INTENSITY GUIDANCE IS MIXED, WITH THE MESOSCALE MODELS BACKING OFF
AND SHOWING LITTLE TO NO ADDITIONAL INTENSIFICATION THROUGH THE
FORECAST PERIOD, WHILE THE DECAY-SHIPS (BOTH VERSIONS) ARE THE MOST
AGGRESSIVE OF THE MODELS, TAKING THE SYSTEM UP TO ABOUT 75 KNOTS.
ADDITIONALLY, THE RIPA AND RICN RI AIDS ARE TRIGGERED, PEAKING OUT
AT 95 KNOTS BY TAU 24. THE JTWC FORECAST TRACKS THE GFS SHIPS
GUIDANCE CLOSELY AND THEN REJOINS THE CONSENSUS MEAN BY TAU 48.
CONFIDENCE IS MEDIUM THROUGHOUT THE FORECAST PERIOD DUE TO THE
UNCERTAINTIES SURROUNDING THE POTENTIAL RI.

[cycloneye]

 https://twitter.com/zoom_earth/status/1724534296856138223