Typhoon 25W(MALOU) forecast to reach CAT 2 by 24hours/TD 26W now over-land, 27/09utc updates

JTWC IS ISSUING 6HOURLY AND 3HOURLY SATELLITE BULLETINS ON TY 25W. WARNING 4/FINAL WAS ISSUED ON TD 26W. 3HOURLY SATELLITE BULLETINS ARE STILL ISSUED ON THE OVER-LAND REMNANTS OF 26W.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: FROM A TRACK PERSPECTIVE, THE FORECAST IS A RELATIVE STRAIGHT-FORWARD RECURVE SCENARIO, WITH TY 25W STEADILY ACCELERATING TO THE NORTHEAST AROUND THE PERIPHERY OF THE SUBTROPICAL RIDGE(STR) THROUGH THE DURATION OF THE FORECAST. THE INTENSITY FORECAST IS A BIT MORE UNCERTAIN HOWEVER. ENVIRONMENTALLY, ALL THE NECESSARY INGREDIENTS INCLUDING VERY LOW VWS, WARM SSTS AND VERY STRONG POLEWARD OUTFLOW, ARE IN PLACE TO SUPPORT FAST OR EVEN RAPID INTENSIFICATION WITHIN THE NEXT 24 HOURS. THE KEY QUESTIONS REVOLVE AROUND THE IMPACT OF MODERATE MID-LEVEL SHEAR, WHICH THE HIGH RESOLUTION HWRF AND THE 0000Z SOUNDING FROM CHICHI-JIMA, INDICATE IS RUNNING AT ABOUT 15-18 KNOTS FROM THE EAST, AND MID-LEVEL DRY AIR WHICH THE CHICHI-JIMA SOUNDING SHOWED BETWEEN 550MB TO 780MB. THESE TWO FACTORS ARE THE ONLY TWO FACTORS THAT COULD HINDER TY 25W FROM EXPLODING. THE CURRENT FORECAST CALLS FOR FAST, BUT NOT RAPID, INTENSIFICATION TO A PEAK OF 90 KNOTS BY 36H. SHORTLY AFTER THE PEAK THE SYSTEM WILL CROSS THE 26C ISOTHERM, AND VWS WILL VERY QUICKLY INCREASE TO BEYOND 30 KNOTS, WHICH WILL LEAD TO STEADY WEAKENING IMMEDIATELY AFTER REACHING THE PEAK INTENSITY. THE SYSTEM WILL BEGIN EXTRA-TROPICAL TRANSITION (ETT) BY 48H WHILE CONTINUING TO STEADILY WEAKEN. ETT IS FORECAST TO BE COMPLETE NO LATER THAN 72H, BUT LIKELY AROUND 60H, AS THE SYSTEM BECOMES EMBEDDED IN THE BAROCLINIC ZONE AND TRANSITIONS TO A COLD CORE LOW.

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) ANALYSIS REVEALS THAT TY 25W IS UNDERGOING A FAIRLY RAPID CONSOLIDATION PHASE, WITH DEEP CONVECTION FLARING AND WRAPPING INTO A RAGGED EYE FEATURE. WHILE THE EYE IN THE VISIBLE AND INFRARED IMAGERY IS RAGGED AND DISORGANIZED, A 270620Z GMI 37GHZ MICROWAVE IMAGE SHOWED A VERY WELL-DEFINED MICROWAVE EYE WITH DEEP CONVECTION FORMING A SOLID EYEWALL COMPLETELY ENCLOSING THE MICROWAVE EYE. ADDITIONALLY, AND SOMEWHAT OMINOUSLY, THE 37GHZ COLOR COMPOSITE IMAGE REVEALED A CLASSIC CYAN RING FEATURE, WHICH SUGGESTS THE POSSIBILITY OF NEAR-TERM RAPID INTENSIFICATION. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE AFOREMENTIONED MICROWAVE IMAGE. THE INITIAL INTENSITY OF 65 KNOTS IS ASSESSED WITH HIGH CONFIDENCE, IN LINE WITH THE MAJORITY OF THE AGENCY FIXES AND THE SATCON ESTIMATE. THE ADT HAS YET TO PICK UP ON THE EYE FEATURE AND IS USING THE CURVED BAND METHOD, AND THUS IS SIGNIFICANTLY LOWER THAN ALL OTHER ESTIMATES AND IS DISCOUNTED. ANALYSIS REVEALS A FAVORABLE ENVIRONMENT, WITH WARM SSTS, LOW VWS AND ROBUST POLEWARD OUTFLOW INTO THE RIGHT ENTRANCE REGION OF A 150 KNOT JET MAX EAST OF HOKKAIDO. WHILE THE SYSTEM IS COCOONED WITHIN AN AREA OF RELATIVELY DRIER AIR, IT APPEARS TO NO LONGER BE ENTRAINING THIS DRY AIR INTO THE CORE, ALLOWING FOR THE CORE TO CONSOLIDATE.

MODEL DISCUSSION: TRACK GUIDANCE IS VERY GOOD CROSS-TRACK AGREEMENT THROUGH THE DURATION OF THE FORECAST, WITH SPREAD GRADUALLY INCREASING TO A VERY MODEST 305KM AT 72H. ALONG-TRACK SPREAD IS GOOD UP TO ABOUT 48H, WHERE AFTER IT DRAMATICALLY INCREASES AS THE SYSTEM ACCELERATES NORTHEASTWARD WHILE UNDERGOING ETT. THE JTWC FORECAST IS DOWN THE CENTER OF THE TRACK ENVELOPE BUT SLIGHTLY SLOWER THAN THE CONSENSUS MEAN WITH HIGH CONFIDENCE. ALL MEMBERS OF THE INTENSITY CONSENSUS AGREE ON THE INTENSIFICATION SCENARIO AND THE BULK OF THE MEMBERS ARE TIGHTLY PACKED WITH A PEAK BETWEEN 75-85 KNOTS. THE HWRF IS THE SOLE OUTLIER, INDICATING RAPID INTENSIFICATION TO A PEAK OF 105 KNOTS BY 36H. WHILE THE RAPID INTENSIFICATION PREDICTION AID (RIPA) DID NOT TRIGGER WITH THIS MODEL RUN, RIPA CALCULATIONS GENERATE ABOUT A 20 PERCENT CHANCE OF RI. THE JTWC FORECAST LIES ABOVE THE CONSENSUS MEAN AS A NOD TO THE LOW, BUT NOT ZERO, PROBABILITY RI, BUT ABOUT 10-15 KNOTS BELOW THE AGGRESSIVE HWRF SOLUTION THROUGH 36H, THEN IS ABOUT FIVE KNOTS ABOVE THE MEAN THEREAFTER.

TRACK AND INTENSITY GUIDANCE FOR THE REMNANTS OF TD 26W.

27/0845UTC.