ZCZC MIATCDAT3 ALL TTAA00 KNHC DDHHMM TROPICAL DEPRESSION LISA DISCUSSION NUMBER 21 NWS NATIONAL HURRICANE CENTER MIAMI FL AL132016 500 PM AST SAT SEP 24 2016 Lisa has been devoid of thunderstorm activity since the convective burst dissipated shortly after 1200 UTC. Assuming some additional spin down since the ASCAT pass this morning, the initial wind speed is lowered to 30 kt, making Lisa a tropical depression again. Meteosat dust product images from the GOES-R Proving Ground indicate that a plume of Saharan dust is approaching Lisa from the east. This dry air combined with westerly shear should cause the depression to degenerate to a remnant low by tonight and continue weakening during the next day or two. The global models are in fair agreement in showing the low opening into a trough in 36 to 48 hours before it gets absorbed by a cold front. Lisa is moving northwestward at 10 kt. A gradual turn to the north is expected during the next day or two while the high pressure system to the north of Lisa shifts eastward. The NHC track forecast is slightly to the left of the previous one, and is in best agreement with the various consensus aids. FORECAST POSITIONS AND MAX WINDS INIT 24/2100Z 25.3N 39.7W 30 KT 35 MPH 12H 25/0600Z 26.4N 41.1W 30 KT 35 MPH...POST-TROP/REMNT LOW 24H 25/1800Z 28.4N 42.0W 25 KT 30 MPH...POST-TROP/REMNT LOW 36H 26/0600Z 30.5N 42.4W 20 KT 25 MPH...POST-TROP/REMNT LOW 48H 26/1800Z...DISSIPATED $$ Forecaster Cangialosi NNNN