ZCZC MIATCDAT1 ALL TTAA00 KNHC DDHHMM TROPICAL DEPRESSION FIONA DISCUSSION NUMBER 26 NWS NATIONAL HURRICANE CENTER MIAMI FL AL062016 500 AM AST TUE AUG 23 2016 Fiona is barely holding on as a tropical cyclone with a small burst of deep convection confined mainly to the southeastern quadrant due to moderate to strong northwesterly vertical wind shear. The initial intensity is being maintained at 30 kt based on a Dvorak intensity estimate of 2.0/30 kt from TAFB, and an ADT estimate of T2.2/32 kt from UW-CIMSS. The initial motion is a little slower at 290/11 kt. Fiona is forecast to gradually turn northwestward and decelerate as the small cyclone moves toward and into a break in the Bermuda-Azores ridge. The NHC forecast track is down the middle of the tightly packed model guidance, and lies close to consensus track model TVCN. Strong westerly to northwesterly vertical wind shear that has been plaguing Fiona for the past several days is forecast to weaken considerably during the next 36 hours, which would normally support some strengthening. However, the small cyclone is expected to remain embedded in a region of dry mid-level air with humidity values less than 60 percent during that time, decreasing to less than 50 percent by 72 hours, which should inhibit the development of persistent deep convection near the center. The result is that Fiona is forecast to degenerate into a remnant low in 48 hours, if not sooner. The official intensity forecast remains below the consensus model IVCN and the SHIPS/LGEM models, and instead follows the weakening trend depicted in the global models. FORECAST POSITIONS AND MAX WINDS INIT 23/0900Z 25.8N 63.4W 30 KT 35 MPH 12H 23/1800Z 26.2N 65.0W 30 KT 35 MPH 24H 24/0600Z 27.1N 67.0W 25 KT 30 MPH 36H 24/1800Z 28.1N 68.6W 25 KT 30 MPH 48H 25/0600Z 28.9N 69.5W 25 KT 30 MPH...POST-TROP/REMNT LOW 72H 26/0600Z 30.0N 70.8W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 27/0600Z 30.6N 71.6W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 28/0600Z...DISSIPATED $$ Forecaster Stewart NNNN