000 WTNT42 KNHC 082038 TCDAT2 HURRICANE OTTO DISCUSSION NUMBER 11 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL172010 500 PM AST FRI OCT 08 2010 OTTO CONTINUES TO MAINTAIN A CENTRAL DENSE OVERCAST WITH CLOUD TOPS COLDER THAN -80C NEAR THE CENTER...ALONG WITH AN AREA OF OUTER BANDING OVER THE EASTERN SEMICIRCLE. SATELLITE INTENSITY ESTIMATES ARE 77 KT FROM SAB AND 65 KT FROM TAFB...AND THERE IS A RECENT CIMSS AMSU INTENSITY ESTIMATE OF 63 KT. THE INITIAL INTENSITY IS INCREASED TO 70 KT AS A BLEND OF THESE DATA. THE CIRRUS OUTFLOW IS GOOD IN THE NORTHEASTERN SEMICIRCLE AND FAIR/POOR ELSEWHERE. THE INITIAL MOTION IS NOW 055/18. THERE IS LITTLE CHANGE IN THE FORECAST PHILOSOPHY...GUIDANCE...OR FORECAST TRACK DURING THE FIRST 72 HR OF THE FORECAST. OTTO IS BECOMING EMBEDDED IN THE STRONG SOUTHWESTERLY FLOW OVER THE CENTRAL ATLANTIC...AND IT SHOULD MOVE RAPIDLY NORTHEASTWARD FOR THE NEXT THREE DAYS OR SO. AFTER 72 HR...THE GUIDANCE HAS BECOME DIVERGENT. WHILE THE GFS...GFS ENSEMBLE MEAN...AND HWRF STILL SHOW A TURN TOWARD THE SOUTHEAST... THE UKMET...CANADIAN...NOGAPS...AND GFDL NOW SHOW A CONTINUED NORTHEASTWARD MOTION. THE ECMWF IS IN BETWEEN THESE CAMPS... FORECASTING OTTO TO MOVE NORTHEASTWARD FOR 84-96 HR BEFORE SHARPLY TURNING IT DUE SOUTH. THE NEW FORECAST TRACK GENERALLY FOLLOWS THE GFS SCENARIO...BUT IS SHIFTED TO THE NORTH OUT OF RESPECT FOR THE OTHER MODELS. HOWEVER...THIS PART OF THE FORECAST TRACK STILL LIES WELL TO THE RIGHT OF THE CENTER OF THE GUIDANCE ENVELOPE...AND MORE NORTHWARD ADJUSTMENT OF THE TRACK COULD BE NEEDED LATER. OTTO WILL SPEND 12-24 HR IN A LIGHT VERTICAL WIND SHEAR/WARM SEA SURFACE TEMPERATURE ENVIRONMENT...AND THE INTENSITY FORECAST THUS SHOWS A LITTLE MORE STRENGTHENING DURING THAT TIME. AFTER 24 HR... INCREASING SHEAR AND DECREASING SEA SURFACE TEMPERATURES SHOULD START A WEAKENING TREND. EXTRATROPICAL TRANSITION IS EXPECTED TO BEGIN AT ABOUT 48 HR AND BE COMPLETE BY 72 HR. HOWEVER...THERE IS STILL A FAIR AMOUNT OF UNCERTAINTY REGARDING THE COMPLETION OF THIS PROCESS DUE TO DISAGREEMENT IN THE DYNAMICAL MODELS ON HOW CLOSE OTTO WILL BE TO THE MAIN BAROCLINIC ZONE OVER THE NORTH ATLANTIC. FORECAST POSITIONS AND MAX WINDS INITIAL 08/2100Z 26.8N 62.3W 70 KT 12HR VT 09/0600Z 28.7N 59.5W 75 KT 24HR VT 09/1800Z 31.3N 54.6W 75 KT 36HR VT 10/0600Z 34.3N 48.2W 70 KT 48HR VT 10/1800Z 38.2N 40.6W 65 KT 72HR VT 11/1800Z 42.0N 30.0W 50 KT...POST-TROP/EXTRATROP 96HR VT 12/1800Z 41.0N 25.0W 40 KT...POST-TROP/EXTRATROP 120HR VT 13/1800Z 39.0N 20.0W 40 KT...POST-TROP/EXTRATROP $$ FORECASTER BEVEN