TD 14W to intensify significantly next 5 days// INVEST 94W// TS 06L(FRANCINE) intensifying// 1003utc

JTWC IS ISSUING 6HOURLY WARNINGS AND 3HOURLY SATELLITE BULLETINS ON 14W.

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS PERSISTENT FLARING AND DEEP CONVECTION DIRECTLY OVER THE LOW-LEVEL CIRCULATION CENTER (LLCC) OF TROPICAL DEPRESSION (TD) 14W. LOW-LEVEL CONVECTIVE BANDS HAVE STARTED TO ORGANIZE ALONG THE WESTERN PERIPHERY OF THE BROAD CYCLONIC FLOW OVER THE LAST FEW HOURS, WHILE OBSERVABLE UPPER-LEVEL POLEWARD OUTFLOW HAS CONTINUED TO AID AND IMPROVE THE OVERALL CONSOLIDATION TD 14W. THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED ON THE 092313Z 89 GHZ GPM MICROWAVE IMAGE SHOWING IMPROVED LOW-LEVEL CONVECTIVE CLOUD LINES CURVING INTO THE ASSESSED POSITION. THE INITIAL INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON A PARTIAL 092257Z ASCAT-B IMAGE SHOWING A SWATH OF 25 KTS INTENSITIES THROUGHOUT THE EASTERN SEMICIRCLE AND AGENCY ESTIMATES LISTED.

FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THIS INITIAL PROGNOSTIC REASONING MESSAGE ESTABLISHES THE FORECAST PHILOSOPHY. FORECAST DISCUSSION: TD 14W WILL TRACK GENERALLY NORTHWESTWARD THROUGHOUT THE FORECAST PERIOD ALONG THE WESTERN PERIPHERY OF THE SUBTROPICAL RIDGE. THE SYSTEM IS EXPECTED TO STEADILY INTENSIFY THROUGH TAU 72 AS THE ENVIRONMENT REMAINS CONDUCIVE FOR FURTHER DEVELOPMENT WITH VERTICAL WIND SHEAR (VWS) REMAINING LESS THAN 15 KTS, SEA SURFACE TEMPERATURES MAINTAIN AVERAGES ABOVE 30 C, AND UPPER-LEVEL OUTFLOW AIDS IN SUSTAINED INTENSIFICATION. AS THE SYSTEM CONTINUES TO TRACK TO THE NORTHWEST ALONG THE WESTERN EDGE OF THE STEERING RIDGE, A CONTINUED CONDUCIVE ENVIRONMENT WILL ALLOW TD 14W TO MAINTAIN STEADY TO MODERATE INTENSIFICATION WITH ASSOCIATED SUPPORTIVE OCEAN HEAT CONTENT (OHC) VALUES THROUGH THE CORRIDOR TO MINAMI DAITO JIMA. FOLLOWING TAU 72, MODERATE INTENSIFICATION TO 100 KTS BY TAU 120 IS FORECASTED AS THE SYSTEM ACCELERATES NORTHWESTWARD AS IT APPROACHES KADENA WITH IMPROVING UPPER-LEVEL POLEWARD OUTFLOW.

MODEL DISCUSSION: DETERMINISTIC MODEL GUIDANCE USED IN THE JTWC CONSENSUS (CONW) REMAINS IN MODERATE AGREEMENT WITH A CROSS-TRACK SPREAD OF 130 NM BY TAU 72, INCREASING TO 135 NM BY TAU 120. PROBABILISTIC GUIDANCE FROM ECMWF (EPS) AND GFS (GEFS) ENSEMBLES ARE IN GOOD AGREEMENT THAT A GENERALLY NORTHWEST TRACK WILL CONTINUE THROUGHOUT THE 120 HOUR FORECAST PERIOD, LENDING MEDIUM CONFIDENCE TO THE JTWC TRACK FORECAST. INTENSITY GUIDANCE REMAINS IN MEDIUM CONFIDENCE THROUGH TAU 72, AS STEADY TO MODERATE INTENSIFICATION IS EXPECTED, HOWEVER, DETERMINISTIC INTENSITY GUIDANCE PAST 72 HOURS BECOMES LESS RELIABLE AS GFS HAS ILLUSTRATED A MAX INTENSITY OF ONLY 55 KTS AT TAU 120. THE JTWC INTENSITY FORECAST IS MORE ALIGNED WITH THE COAMPS-TC EPS INTENSITY GUIDANCE, WITH STEADY TO MODERATE INTENSIFICATION FORECASTED INTO TAU 84, WHILE A PERIOD OF RAPID INTENSIFICATION WITH PROBABILITIES OF HIGHER 60 PERCENT IS EXPECTED AFTER TAU 84, LENDING LOW CONFIDENCE BETWEEN TAU 72 AND TAU 120.

THE AREA OF CONVECTION (INVEST 94W) PREVIOUSLY LOCATED NEAR 23.4N 131.5E IS NOW LOCATED NEAR 25.8N 125.4E, APPROXIMATELY 129 NM WEST-SOUTHWEST OF KADENA. THE SYSTEM IS CURRENTLY CLASSIFIED AS A MONSOON DEPRESSION-LIKE SYSTEM, GENERALLY CHARACTERIZED AS A LARGE CYCLONIC CIRCULATION, WITH A RADIUS OF MAXIMUM WINDS GREATER THAN 100NM AND THE HIGHEST WINDS CONFINED TO THE NORTHWESTERN PERIPHERY OF THE CIRCULATION AND A WEAK CORE OF LIGHT WINDS. ANIMATED ENHANCED INFRARED IMAGERY DEPICT NO WELL-DEFINED LOW LEVEL CIRCULATION CENTER (LLCC), BUT RATHER A LARGE AREA OF ROTATION. A 092224Z SSMIS2 F-16 91 GHZ MICROWAVE IMAGE DEPICT FRAGMENTED CURVED CONVECTIVE BANDING OVER THE NORTHWESTERN SEMICIRCLE OF THE BROAD CIRCULATION. ENVIRONMENTAL ANALYSIS INDICATES THE 94W IS IN A FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH MODERATE VERTICAL WIND SHEAR OF 15-20 KNOTS, GOOD EASTWARD AND WESTWARD OUTFLOW ALOFT. LASTLY, WARM SEA SURFACE TEMPERATURES OF 29-30 DEGREES C. GLOBAL MODEL GUIDANCE CONTINUE TO SUGGEST THIS SYSTEM WILL CONTINUE TO TRACK WEST-NORTHWESTWARD TOWARDS THE RYUKYU ISLANDS AND DEVELOP SOME ENHANCED WINDS ALONG THE NORTHWESTERN PERIPHERY, BUT LIKELY FAIL TO SHOW TYPICAL TROPICAL CYCLONE FEATURES. FOR HAZARDS AND WARNINGS, REFERENCE THE FLEET WEATHER CENTER SAN DIEGO HIGH WINDS AND SEAS PRODUCT OR REFER TO LOCAL WMO DESIGNATED FORECAST AUTHORITY. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 13 TO 18 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1002 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS LOW.

GLOBAL MODEL GUIDANCE CONTINUE TO SUGGEST THIS SYSTEM WILL CONTINUE TO TRACK WEST-NORTHWESTWARD TOWARDS THE RYUKYU ISLANDS AND DEVELOP SOME ENHANCED WINDS ALONG THE NORTHWESTERN PERIPHERY, BUT LIKELY FAIL TO SHOW TYPICAL TROPICAL CYCLONE FEATURES.