000 WTNT42 KNHC 110239 TCDAT2 TROPICAL STORM KATE DISCUSSION NUMBER 9 NWS NATIONAL HURRICANE CENTER MIAMI FL AL122015 1100 PM AST TUE NOV 10 2015 The overall structure of Kate has not changed much since this afternoon, however, the area of cloud tops has expanded and cooled within the past few hours. NOAA reconnaissance aircraft data from around 0000 UTC showed that the center remains embedded within the central dense overcast, but there was significant tilt between the 700 mb and surface centers. Although flight-level winds and 0000 UTC Dvorak classifications support an intensity of 65 kt, dropwindsonde and SFMR data indicate that the winds aloft are not efficiently mixing down to the surface and the initial intensity remains 60 kt. There is only a short window of opportunity for Kate to reach hurricane strength, before it moves over cooler waters and the shear increases to more than 30 kt by Wednesday morning. Kate is expected to remain a powerful cyclone as it becomes extratropical in about 36 hours. Later in the period, Kate is forecast to gradually weaken as it loses baroclinic forcing. The extratropical low is forecast to be absorbed by a front over the north Atlantic in 4 to 5 days. The initial motion estimate is 055/30 kt. Kate should continue moving rapidly northeastward or east-northeastward during the next 24 hours, then temporarily slow down during the 36 to 48 hour time period while it interacts with an upper-level trough. After that time, the extratropical low should again accelerate northeastward over the north-central Atlantic. The model guidance is in very good agreement on this scenario, and the updated track forecast is essentially an update of the previous advisory. The extratropical portion of Kate's forecast was coordinated with the NOAA Ocean Prediction Center. FORECAST POSITIONS AND MAX WINDS INIT 11/0300Z 33.9N 69.5W 60 KT 70 MPH 12H 11/1200Z 36.0N 64.0W 65 KT 75 MPH 24H 12/0000Z 38.9N 55.7W 65 KT 75 MPH 36H 12/1200Z 41.6N 50.8W 60 KT 70 MPH...POST-TROP/EXTRATROP 48H 13/0000Z 42.6N 49.4W 55 KT 65 MPH...POST-TROP/EXTRATROP 72H 14/0000Z 44.0N 41.0W 45 KT 50 MPH...POST-TROP/EXTRATROP 96H 15/0000Z 50.0N 28.0W 45 KT 50 MPH...POST-TROP/EXTRATROP 120H 16/0000Z...ABSORBED $$ Forecaster Brown