ZCZC MIATCDAT2 ALL TTAA00 KNHC DDHHMM TROPICAL STORM KARL DISCUSSION NUMBER 16 NWS NATIONAL HURRICANE CENTER MIAMI FL AL122016 500 AM AST SUN SEP 18 2016 The structure of Karl has kept a similar appearance for some time now with a small area of convection flaring up and down near the center, with a larger mass of thunderstorms following the center in the northeastern quadrant. The initial wind speed is held at 35 kt using the last TAFB satellite estimate. Karl's disorganized low-level structure will likely prevent much intensification in the short term. However the environment near the tropical cyclone is likely to become conducive for strengthening within a couple of days due to lower shear, slightly more moisture, and warmer sea surface temperatures. The intensity guidance is very similar to the previous model cycle, and only small changes were made to the previous NHC wind speed forecast. The initial motion estimate is 255/10. A large subtropical high over the central Atlantic should provide a fairly well-defined steering current for the tropical storm over the next several days. This ridge will likely turn Karl to the west later today and to the west-northwest by early Tuesday through the end of the period. Other than a small westward adjustment through 72 hours, the new NHC track is similar to the previous one, near a model consensus favoring the faster GFS/ECMWF solutions. FORECAST POSITIONS AND MAX WINDS INIT 18/0900Z 17.7N 42.3W 35 KT 40 MPH 12H 18/1800Z 17.7N 44.3W 35 KT 40 MPH 24H 19/0600Z 18.0N 47.0W 40 KT 45 MPH 36H 19/1800Z 18.6N 49.6W 40 KT 45 MPH 48H 20/0600Z 19.3N 52.2W 45 KT 50 MPH 72H 21/0600Z 21.5N 57.2W 55 KT 65 MPH 96H 22/0600Z 23.9N 62.1W 65 KT 75 MPH 120H 23/0600Z 26.5N 66.5W 75 KT 85 MPH $$ Forecaster Blake NNNN