Official Discussion issued by the National Hurricane Center

Don (AL052023) DATA RELEASED: 7/18/2023 9:00:00 PM UTC

Copy of official data

Tropical Storm Don Discussion Number  19
NWS National Hurricane Center Miami FL       AL052023
900 PM GMT Tue Jul 18 2023

Deep convection has re-developed on the eastern side of Don this 
afternoon, though most of the circulation is pretty skeletal.  The 
initial wind speed remains 35 kt, close to the latest TAFB 
satellite classification, and hopefully the evening scatterometer 
passes will hit the storm for the next advisory to get a more 
precise estimate of the winds.  

The environment near Don gets slightly more conducive for 
strengthening during the next day or two with warmer SSTs, higher 
mid-level moisture, and light or moderate shear.  Gradual 
intensification is shown through Thursday, similar to the last 
forecast and near or below the model consensus.  At long range, the 
storm should pass over its own cool wake, and the environment 
becomes less conducive overall. The model guidance is lower on this 
cycle for late week, closer to the previous NHC wind speed 
prediction.  Thus, little change in strength is shown at days 3-4, 
and Don should lose its deep convection around day 5 when it moves 
north of the Gulf Stream.

Don has slowed and turned southward, now at around 6 kt.  The storm 
should move southwestward on Wednesday and west-northwestward on 
Thursday due to steering from a blocking ridge in the north-central 
Atlantic.   As the ridge slides eastward, Don is likely to head
northward by Saturday and accelerate north-northeastward on Sunday. 
The model spread has increased on this cycle, but there's still a 
tendency for the weaker model solutions to be east of the model 
consensus.  Since the NHC intensity prediction remains on the low 
side of the guidance, it is reasonable for the track forecast to 
remain east of the model consensus, resulting in little net change 
to the NHC track forecast.


INIT  18/2100Z 34.9N  39.2W   35 KT  40 MPH
12H  19/0600Z 34.1N  39.2W   35 KT  40 MPH
24H  19/1800Z 33.7N  40.0W   35 KT  40 MPH
36H  20/0600Z 33.8N  41.2W   40 KT  45 MPH
48H  20/1800Z 34.3N  42.6W   40 KT  45 MPH
60H  21/0600Z 35.2N  44.4W   45 KT  50 MPH
72H  21/1800Z 36.5N  46.3W   45 KT  50 MPH
96H  22/1800Z 40.5N  49.5W   45 KT  50 MPH
120H  23/1800Z 46.0N  47.5W   40 KT  45 MPH...POST-TROPICAL

Forecaster Blake