ZCZC MIATCDEP5 ALL TTAA00 KNHC DDHHMM TROPICAL STORM LINDA DISCUSSION NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL EP152015 300 PM MDT SUN SEP 06 2015 Linda is strengthening. Satellite images indicate that banding features have become better defined during the last several hours, and deep convection has been persisting near the center. The circulation and cloud field of Linda are quite large, extending several hundred miles across. The Dvorak classifications at 1800 UTC have increased to 3.5/55 kt from TAFB, 3.0/45 kt from SAB, and ADT values from UW-CIMSS are around 3.4/53 kt. Based on these estimates, the initial wind speed is raised to 50 kt. Additional strengthening is likely during the next couple of days as the shear is expected to remain relatively light while the cyclone is embedded within a moist air mass and over warm waters. After 48 hours, however, Linda is expected to move over progressively cooler water and into a drier and more stable air mass. These conditions should end the strengthening trend, and induce a gradual weakening. The NHC intensity forecast shows a higher peak intensity than the previous one and leans toward the upper end of the guidance, in best agreement with the SHIPS model. Linda continues to move northwestward at about 9 kt on the southwestern side of a mid-level high pressure system located over northern Mexico and the southern United States. The ridge is expected to be nearly stationary during the next couple of days, which should keep Linda moving northwestward at a similar or slightly faster forward speed. After that time, a slowdown is predicted as the ridge weakens some and shifts westward. The NHC track forecast has again been shifted a little to the north of the previous one, trending toward the latest guidance. FORECAST POSITIONS AND MAX WINDS INIT 06/2100Z 14.8N 109.7W 50 KT 60 MPH 12H 07/0600Z 16.1N 110.9W 60 KT 70 MPH 24H 07/1800Z 18.0N 112.7W 75 KT 85 MPH 36H 08/0600Z 19.7N 114.2W 85 KT 100 MPH 48H 08/1800Z 21.1N 115.5W 85 KT 100 MPH 72H 09/1800Z 23.0N 117.2W 70 KT 80 MPH 96H 10/1800Z 24.6N 119.4W 55 KT 65 MPH 120H 11/1800Z 25.4N 122.0W 40 KT 45 MPH $$ Forecaster Cangialosi NNNN