000 WTPZ41 KNHC 141447 TCDEP1 TROPICAL STORM KARINA DISCUSSION NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112014 800 AM PDT THU AUG 14 2014 Deep convection has continued to increase and expand into a large canopy of cloud tops of -80C to -85C. Passive microwave satellite fixes indicate that the low-level center is located farther into the northeastern portion of the convective cloud shield and that a mid-level eye feature has developed closer to the center of the cloud mass. However, the mid-level eye is displaced or tilted at least 15-20 nmi southwest of the low-level center due to modest northeasterly shear impinging on the cyclone. Despite the shear conditions, satellite intensity estimate from TAFB and SAB are a consensus T3.5/55 kt, and estimates from UW-CIMSS ADT and AMSU are 57 kt and 55 kt, respectively. Based on these data, the initial intensity estimate is raised to 55 kt. The initial motion estimate is 270/09 kt and is based primarily on microwave satellite position fixes over the past 9 hours. The forecast track and reasoning remain unchanged over the past 24 hours with Karina expected to move in a general westward direction during the forecast period due to the presence of a strong subtropical ridge located to the north of the cyclone. By Day 5, however, the forecast become a little murky due to several models developing multiple tropical cyclones in the central Pacific and eastern Pacific basins that begin to interact with Karina in some form or fashion. Rather than committing to any one particular solution, the NHC track forecast just shows a significant slow down in Karina's motion. The official forecast track has been nudged slightly south of the previous advisory track and lies close to the consensus model TVCE, except at 120 hours due to the expected slower forward speed. Northeasterly shear of 10 to 15 kt has been affecting Karina during the past 12 hours or so, and the shear is expected to increase slightly over the next 24 hours. However, other environmental and oceanic conditions are expected to be favorable for additional strengthening to occur, so the NHC intensity forecast still calls for steady strengthening through the next 36 hours or so, followed by a leveling off of the intensity due to the cyclone moving over marginal SSTs near 26C and into a more stable air mass. The official intensity forecast is essentially just an update of the previous forecast, and remains above all of the available intensity guidance but follows the development trend in the SHIPS model. FORECAST POSITIONS AND MAX WINDS INIT 14/1500Z 17.2N 115.9W 55 KT 65 MPH 12H 15/0000Z 17.4N 117.6W 65 KT 75 MPH 24H 15/1200Z 17.6N 119.9W 70 KT 80 MPH 36H 16/0000Z 17.9N 122.2W 75 KT 85 MPH 48H 16/1200Z 18.1N 124.4W 75 KT 85 MPH 72H 17/1200Z 18.2N 128.4W 75 KT 85 MPH 96H 18/1200Z 17.9N 131.4W 70 KT 80 MPH 120H 19/1200Z 17.8N 133.5W 65 KT 75 MPH $$ Forecaster Stewart