Official Discussion issued by the National Hurricane Center

Dolly (AL042020) DATA RELEASED: 6/23/2020 9:00:00 PM UTC

Copy of official data

Tropical Storm Dolly Discussion Number   6
NWS National Hurricane Center Miami FL       AL042020
500 PM AST Tue Jun 23 2020

Dolly's structure has continued to improve somewhat during the day 
with convective banding now extending around the eastern and 
northern side of the circulation.  While water vapor imagery 
indicates that an upper-level low is still in the vicinity of 
Dolly, that feature is displaced from the cyclone a bit, with some
anticyclonic outflow noted in the cirrus canopy.  This 
structure further supports the analysis of Dolly's transition to a 
tropical storm.  For intensity, there is a wide range among 
satellite estimates, with TAFB and SAB ranging from 25-35 kt and 
UW-CIMSS ADT and SATCON estimates between 45-50 kt.  The initial 
intensity will remain 40 kt on this advisory, matching what was 
shown by the earlier scatterometer data.

Dolly continues to move east-northeastward with an initial motion 
of 060/10 kt.  Strengthening mid-latitude southwesterly flow is 
expected to cause Dolly to turn northeastward and begin 
accelerating tonight into Wednesday, and the track guidance is in 
good agreement on the future path and speed of the storm.  Dolly's 
future track will take it over much colder waters and into a 
higher-shear environment over the next day or so, which should 
cause the cyclone to degenerate into a remnant low on Wednesday.  
Dissipation is still shown at 48 hours, but global models fields 
indicate that the circulation could open up before then as the 
system nears the southeastern tip of Newfoundland.


INIT  23/2100Z 40.1N  61.1W   40 KT  45 MPH
12H  24/0600Z 41.2N  59.4W   35 KT  40 MPH
24H  24/1800Z 43.1N  56.9W   30 KT  35 MPH...POST-TROP/REMNT LOW
36H  25/0600Z 45.0N  53.8W   25 KT  30 MPH...POST-TROP/REMNT LOW
48H  25/1800Z...DISSIPATED

Forecaster Berg