000
WTNT44 KNHC 041530
TCDAT4
 
Tropical Storm Dexter Discussion Number   3
NWS National Hurricane Center Miami FL       AL042025
1100 AM AST Mon Aug 04 2025
 
Several bursts of deep convection have formed with Dexter this
morning, but the latest visible satellite images suggest the center
is on the far western edge of the cirrus canopy, partially exposed.
The intensity estimates from SAB and TAFB remain unchanged for 12
UTC, and objective estimates from UW-CIMSS (ADT, DPRINT, DMINT)
support maintaining a current intensity of 40 kt this advisory.
 
Dexter continues to move northeastward, a bit faster than earlier at
050/12 kt. This general motion is forecast to continue for the next
couple of days with a brief slowdown as the storm is steered by a
narrow subtropical ridge located to its southeast. In around 60 h, a
shortwave trough dropping southward from Atlantic Canada may try to
phase with Dexter. However, the global and ensemble model guidance
is split if their interaction will be favorable, causing the storm
to accelerate northeastward, or unfavorable, leaving Dexter behind
as a convection-less remnant low. For this cycle, the track
guidance has shifted a bit faster to the northeast, and the NHC
track has also been shifted faster, but generally along the same
track as the previous advisory. It is worth noting that the Google
Deep Mind ensemble mean (GDMI) is a significant fast outlier, and it
will be interesting to see if the overall model guidance continues
to trend faster with Dexter's motion.
 
Intensity-wise, Dexter is likely to face an increasingly hostile 
environment, with westerly vertical wind shear increasing above 30 
kt in about 24 h. Thus, only a little additional strengthening is 
shown in the forecast for today, then capping the intensity at 45 kt 
through the rest of this week. However, since the cyclone will 
remain over the warm Gulf Stream waters until it passes poleward of 
40N, it will likely continue to produce periodic bursts of deep 
convection, helping to maintain its intensity in the face of the 
unfavorable shear. After 60 h, the guidance remains split on whether 
or not Dexter will become a remnant low, or phase with the 
upper-level trough nearby, becoming a stronger extratropical low. 
While the latest intensity forecast shows the latter solution 
panning out, as mentioned previously, Dexter's final structure 
remains quite uncertain near the end of the forecast period.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  04/1500Z 35.2N  67.4W   40 KT  45 MPH
 12H  05/0000Z 36.5N  65.4W   45 KT  50 MPH
 24H  05/1200Z 37.6N  63.4W   45 KT  50 MPH
 36H  06/0000Z 38.5N  61.6W   45 KT  50 MPH
 48H  06/1200Z 39.4N  59.1W   45 KT  50 MPH
 60H  07/0000Z 40.1N  55.4W   45 KT  50 MPH
 72H  07/1200Z 41.0N  50.7W   45 KT  50 MPH...POST-TROP/EXTRATROP
 96H  08/1200Z 43.9N  43.5W   45 KT  50 MPH...POST-TROP/EXTRATROP
120H  09/1200Z 46.5N  36.1W   45 KT  50 MPH...POST-TROP/EXTRATROP
 
$$
Forecaster Papin