000 WTPZ41 KNHC 191432 TCDEP1 TROPICAL STORM KARINA DISCUSSION NUMBER 27 NWS NATIONAL HURRICANE CENTER MIAMI FL EP112014 800 AM PDT TUE AUG 19 2014 The cloud pattern associated with Karina has changed very little during the past few hours. There is a well-defined convective band wrapping around the center, but there is some dry air entraining into the cyclone. The convection is not very deep, and Dvorak T-numbers are on a weakening trend supporting an initial intensity of 45 knots. The outflow of large Tropical Storm Lowell located to the east will likely induce some moderate shear over Karina, but should not be strong enough to weaken the cyclone significantly. Karina most likely will experience some fluctuations in intensity during the next 2 to 3 days. After that time, as Karina gradually becomes pulled northeastward by the flow around Lowell, it will encounter cooler waters and the cyclone will likely begin to weaken. Karina is already slowing down and is moving westward at 4 knots. An additional decrease in forward speed is anticipated as the steering currents collapse further, and Karina is expected to drift westward or even meander for the next 2 to 3 days. Then, as Lowell passes to the north, the cyclone should turn northeastward with increased forward speed around the southwesterly flow associated with the large circulation of Lowell. The NHC forecast is very close to the consensus of the GFS and the ECMWF models, which has been performing quite well with Karina so far. It is also similar to the previous NHC forecast. FORECAST POSITIONS AND MAX WINDS INIT 19/1500Z 15.7N 134.4W 45 KT 50 MPH 12H 20/0000Z 15.7N 135.0W 45 KT 50 MPH 24H 20/1200Z 15.8N 135.7W 45 KT 50 MPH 36H 21/0000Z 16.0N 136.2W 45 KT 50 MPH 48H 21/1200Z 16.0N 136.5W 40 KT 45 MPH 72H 22/1200Z 16.0N 136.5W 40 KT 45 MPH 96H 23/1200Z 17.7N 132.3W 35 KT 40 MPH 120H 24/1200Z 21.0N 129.0W 35 KT 40 MPH $$ Forecaster Avila