000 WTPZ45 KNHC 200232 TCDEP5 TROPICAL STORM KIKO DISCUSSION NUMBER 21 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP152007 800 PM PDT FRI OCT 19 2007 THE CLOUD PATTERN HAS NOT BECOME ANY BETTER ORGANIZED DURING THE PAST SEVERAL HOURS. IN FACT...THE ARE ONLY A FEW PATCHES OF DEEP CONVECTION AT THIS TIME...AND MICROWAVE DATA REVEAL THAT THE LOW AND MID -LEVEL CENTERS ARE NOT VERTICALLY ALIGNED. DVORAK T- NUMBERS HAVE NOT CHANGED SIGNIFICANTLY SO THE INITIAL INTENSITY IS KEPT AT 45 KNOTS...AND THIS APPEARS TO BE GENEROUS. THERE IS A DISCREPANCY BETWEEN SHIPS AND THE GFDL/HWRF MODELS. SHIPS ONLY SHOWS A MODEST STRENGTHENING AND BARELY BRINGS KIKO TO HURRICANE STRENGTH WHILE THE TWO OTHER MODELS MAKE KIKO A STRONGER HURRICANE. THERE ARE NO APPARENT REASONS WHY KIKO SHOULD NOT STRENGTHEN. THE SHEAR IS RELATIVELY LOW AND IS NOT EXPECTED TO INCREASE DURING THE NEXT DAY OR TWO WHILE KIKO IS MOVING OVER WARM WATERS. GIVEN THESE CONDITIONS...THE OFFICIAL FORECAST INSISTS ON A GRADUAL STRENGTHENING AND KIKO SHOULD BECOME A HURRICANE IN ABOUT A DAY OR TWO. KIKO HAS BEEN MOVING VERY SLOWLY TOWARD THE NORTHWEST OR 305 DEGREES AT 4 KNOTS. A DEVELOPING RIDGE OVER MEXICO WILL LIKELY KEEP KIKO ON THE SAME GENERAL SLOW MOTION FOR THE NEXT 24 TO 36 HOURS. THEREAFTER...THE TRACK FORECAST BECOMES HIGHLY UNCERTAIN...I EMPHASIZE...HIGHLY UNCERTAIN. RELIABLE MODELS LIKE THE GFS AND THE ECMWF DEVELOP A STRONG RIDGE NORTH OF KIKO AND EVENTUALLY FORCE THE CYCLONE TO TURN WESTWARD BEFORE REACHING BAJA CALIFORNIA. THE EQUALLY RELIABLE UK AND GFDL/HWRF GROUP SHOWS A MORE NORTHERLY COMPONENT TOWARDS BAJA CALIFORNIA OR EVEN TO THE AREA OF CABO CORRIENTES AND THE SEA OF CORTES. AT THIS TIME...THE OFFICIAL FORECAST FOLLOWS THE GFS/ECMWF SOLUTION AND THE PREVIOUS OFFICIAL FORECAST...TURNING KIKO WESTWARD JUST TO THE SOUTH OF BAJA CALIFORNIA AND AWAY FROM MEXICO. HOWEVER...WE MUST BE READY TO MAKE A BIG CHANGE IN THE FORECAST IF THE NORTHWARD TREND SUGGESTED BY THE UK/GFDL/HWRF RUNS BEGINS TO MATERIALIZE. THIS OPTION COULD RESULT IN A STRONGER CYCLONE SINCE THE OCEAN IS VERY WARM NEAR THE SOUTHWEST COAST OF MAINLAND MEXICO. SO STAY TUNED. FORECAST POSITIONS AND MAX WINDS INITIAL 20/0300Z 17.7N 105.9W 45 KT 12HR VT 20/1200Z 18.1N 106.4W 50 KT 24HR VT 21/0000Z 19.0N 107.3W 55 KT 36HR VT 21/1200Z 19.7N 107.8W 65 KT 48HR VT 22/0000Z 20.5N 108.5W 75 KT 72HR VT 23/0000Z 21.0N 109.5W 75 KT 96HR VT 24/0000Z 21.5N 111.5W 65 KT 120HR VT 25/0000Z 22.0N 114.5W 50 KT $$ FORECASTER AVILA