000 WTPZ45 KNHC 182032 TCDEP5 TROPICAL STORM KIKO DISCUSSION NUMBER 16 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP152007 200 PM PDT THU OCT 18 2007 AFTERNOON SATELLITE IMAGERY INDICATES THAT KIKO IS GRADUALLY BECOMING BETTER ORGANIZED...WITH INCREASING CONVECTIVE BANDS NEAR THE CENTER AND IMPROVING CIRRUS OUTFLOW. THE BANDING HAS NOT YET INCREASED ENOUGH TO RAISE THE SATELLITE INTENSITY ESTIMATES...SO THE INITIAL INTENSITY REMAINS 35 KT. THE LATEST ANALYSIS FROM CIMSS AT THE UNIVERSITY OF WISCONSIN NOW SHOW ABOUT 15 KT OF EASTERLY VERTICAL WIND SHEAR AFFECTING THE STORM. THE CENTER IS STILL BROAD AND HARD TO PIN DOWN EVEN WITH MICROWAVE IMAGERY...BUT IT MAY BE A LITTLE WEST OF THE POSITION IN PREVIOUS ADVISORY. THE INITIAL MOTION IS NOW A SOMEWHAT UNCERTAIN 360/3. IN THE FIRST 48 HR OR SO...KIKO SHOULD MOVE SLOWLY NORTHWARD TO NORTHWESTWARD AS PRESSURES RISE OVER NORTHERN MEXICO IN THE WAKE OF AN EASTWARD-MOVING DEEP-LAYER TROUGH OVER THE CENTRAL UNITED STATES. AFTER 48 HR...UNCERTAINTY REMAINS REGARDING THE HANDLING OF A SECOND TROUGH OVER THE WESTERN AND CENTRAL U.S. THE GFS CONTINUES TO BUILD ENOUGH RIDGE BETWEEN KIKO AND THE TROUGH TO TURN THE STORM WESTWARD. IN A NOTABLE CHANGE FROM ITS PREVIOUS RUN... THE ECMWF NOW SHOWS MORE RIDGING NORTH OF KIKO AND A NORTHWESTWARD TO WESTWARD MOTION SIMILAR TO THE GFS. THE UKMET CONTINUES TO BUILD THE RIDGE AFTER 48 HR...BUT IN A TWIST MOVES THE STORM NORTHWARD INTO MEXICO BEFORE THE RIDGE BUILDS IN. THE NOGAPS AMPLIFIES THE TROUGH INTO THE SOUTHWESTERN U.S. IN A PATTERN THAT WOULD CAUSE A NORTHWARD MOTION INTO MEXICO. THE GFDL AND HWRF CALL FOR A GENERALLY NORTHWESTWARD MOTION AT A MUCH FASTER SPEED THAN THE OTHER MODELS. THE NEW FORECAST TRACK WILL BE SIMILAR TO BUT LEFT OF THE PREVIOUS FORECAST FOR THE FIRST 48 HR. AFTER THAT...IT CALLS FOR A GRADUAL BEND TOWARD THE WEST-NORTHWEST IN RESPONSE TO THE BUILDING RIDGE. THIS PART OF THE TRACK IS LEFT OF AND SOMEWHAT FASTER THAN THE PREVIOUS FORECAST...AT ABOUT THE SPEED OF THE ECMWF AND THE FSU SUPERENSEMBLE. UPPER-LEVEL WINDS HAVE BECOME MORE FAVORABLE FOR DEVELOPMENT...WITH THE LARGE-SCALE MODELS FORECASTING THEM TO REMAIN FAVORABLE FOR AT LEAST THE NEXT 48-72 HR. SINCE KIKO IS FORECAST TO REMAIN FARTHER FROM LAND...THE FORECAST INTENSITIES HAVE BEEN SIGNIFICANTLY INCREASED FROM THE PREVIOUS ADVISORY. THE NEW INTENSITY FORECAST CALLS FOR KIKO TO BECOME A HURRICANE IN 36-48 HR...AND THEN PEAK AT ABOUT 96 HR AS IT ENCOUNTERS INCREASING SHEAR. THE NEW INTENSITIES ARE HIGHER THAN THOSE OF THE SHIPS MODEL...BUT BELOW THOSE OF THE GFDL...HWRF...AND THE INTENSITY CONSENSUS. FORECAST POSITIONS AND MAX WINDS INITIAL 18/2100Z 16.8N 103.7W 35 KT 12HR VT 19/0600Z 17.2N 103.7W 40 KT 24HR VT 19/1800Z 17.7N 103.9W 50 KT 36HR VT 20/0600Z 18.3N 104.5W 60 KT 48HR VT 20/1800Z 18.9N 105.1W 70 KT 72HR VT 21/1800Z 19.5N 106.0W 80 KT 96HR VT 22/1800Z 21.0N 107.5W 85 KT 120HR VT 23/1800Z 22.0N 109.5W 85 KT $$ FORECASTER BEVEN