Subtropical Storm Ernesto Discussion Number 4
Wiki-Hurricanes Forecast Center
5:00 AM AST Thu Aug 16 2018
Ernesto has changed little in organization. Modest convection continues to fire north and east of the low-level circulation, a sign that the immediate environment continues to moisten, but it is not yet centrally focused. Upper-level outflow is not yet expanding either, a sign that Ernesto is still wholly embedded within the upper-level trough that allowed for its formation. There is still opportunity for Ernesto to strength and acquire tropical characteristics today, but a northeast track ahead of an upper-level trough should send the storm into colder waters, a drier environment, and higher wind shear beginning tomorrow. Degeneration to a remnant low is expected in about 24 hours. More recent models are keeping the post-tropical cyclone a separate entity from the frontal system, and this is reflected in the updated forecast, which calls for dissipation in 4 days now.
INIT 16/0900Z 35 KT 40 MPH...SUBTROPICAL STORM
12H 16/1800Z 40 KT 45 MPH...TROPICAL STORM
24H 17/0600Z 40 KT 45 MPH...POST-TROP/EXTRATROP
36H 17/1800Z 40 KT 45 MPH...POST-TROP/EXTRATROP
48H 18/0600Z 45 KT 50 MPH...POST-TROP/EXTRATROP
72H 19/0600Z 35 KT 40 MPH...POST-TROP/EXTRATROP...INLAND OVER UNITED KINGDOM
96H 20/0600Z...DISSIPATED