Despite its current very large eye Typhoon 25W(MALOU) is still forecast to reach CAT 2 within 24hours, 28/06utc update

JTWC IS ISSUING 6HOURLY WARNINGS AND 3HOURLY SATELLITE BULLETINS ON TY 25W.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TYPHOON 25W (MALOU) WILL CONTINUE TRACKING NORTHEASTWARD, ACCELERATING DRAMATICALLY DURING THE FORECAST PERIOD AS IT MOVES BENEATH A MID-LATITUDE JET STREAK EAST OF JAPAN. THIS SAME JET STREAK IS CURRENTLY INTERACTING CONSTRUCTIVELY WITH MALOU'S UPPER-LEVEL OUTFLOW, WHICH HAS LIKELY CONTRIBUTED TO THE OBSERVED INTENSIFICATION OF THE TYPHOON OVER THE PAST 24 HOURS. SOME FURTHER INTENSIFICATION IS POSSIBLE DURING THE NEXT 12-24 HOURS WHILE MALOU TRACKS OVER WARM WATER AND VERTICAL SHEAR REMAINS MODERATE. THE FORECAST PEAK INTENSITY IS 90 KNOTS/CAT 2 AT 24H, STAYING BELOW THE AGGRESSIVE HWRF MODEL, WHICH THINKS THE INNER CONVECTIVE CORE IS MORE COMPLETE AND ROBUST THAN IN REALITY. AFTER 24 HOURS, OCEAN TEMPERATURES BENEATH THE TYPHOON WILL RAPIDLY DECREASE, COINCIDENT WITH AN INCREASE IN VERTICAL SHEAR AS MALOU NEARS THE MID-LATITUDE JET, LEADING TO A RAPID TRANSITION TO AN EXTRATROPICAL CYCLONE BY 48 HOURS WITH MAXIMUM WINDS OF AROUND 50 KNOTS.

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS A LARGE EYE 150/165 KM IN DIAMETER WITH MULTIPLE EMBEDDED MESOVORTICES. THE RING OF DEEP CONVECTION ENCIRCLING THE EYE HAS ERODED ON THE SOUTHERN SIDE DURING THE PAST SIX HOURS, AND THE INNER CORE MAINTAINS A GENERALLY RAGGED APPEARANCE. GFS MODEL DIAGNOSTICS SHOW THAT THE STRONGEST VERTICAL SHEAR IS IN THE 850-450 MB LAYER, COLOCATED WITH A MID-LEVEL DRY AIR LAYER TO THE WEST OF THE TYPHOON. THE RESULTING INWARD TRANSPORT OF DRY MID-LEVEL AIR INTO THE CORE OF THE CYCLONE MAY BE CONTRIBUTING TO THE RAGGED CONVECTIVE STRUCTURE. THE INITIAL INTENSITY IS HELD STEADY AT 80 KNOTS/CAT 1 BASED ON A 272030Z SENTINNEL-1B SAR PASS SHOWING A BAND OF 75-80 KNOT WINDS IN THE SOUTHEAST QUADRANT, BROADLY SUPPORTED BY SUBJECTIVE DVORAK ESTIMATES OF T4.5 (77 KT) AND T5.0 (90 KT) FROM VARIOUS AGENCIES.

MODEL DISCUSSION: MODEL GUIDANCE IS TIGHTLY CLUSTERED THROUGH 48 HOURS, WITH MODERATE ALONG-TRACK SPREAD AT 24-48 HOURS. THE JTWC TRACK FORECAST IS SIMILAR TO THE PREVIOUS ONE. THE JTWC INTENSITY FORECAST IS CLOSE TO THE MULTI-MODEL CONSENSUS, STAYING BELOW THE AGGRESSIVE HWRF AND COAMPS-TC MODELS BUT STRONGER THAN THE GFS.

28/0715UTC.