Tropical Storm Joyce Discussion Number   1
NWS National Hurricane Center Miami FL       AL112024
1100 AM AST Fri Sep 27 2024

Tropical Storm Joyce has formed over the central tropical Atlantic 
Ocean, becoming the tenth named storm in the basin this season.  
First-light visible satellite imagery showed low-level clouds 
moving westward, indicating the surface circulation has closed.  
Deep, organized convection has been persistent for the past day or 
so with decent outflow noted in the northern semicircle of the 
circulation.  This initial intensity is set to 35 kt, representing 
the subjective satellite estimates from both TAFB and SAB.

Joyce has a short window for potential intensification.  For the 
next day or so, deep-layer vertical wind shear should be 
moderate-to-low with warm sea surface temperatures along the 
forecast track.  Mid-level humidities around Joyce are sufficient, 
but expected to dry in the coming days.  Global models predict the 
vertical wind shear should increase and the storm will likely 
experience dry air intrusions.  The official forecast shows Joyce 
strengthening to a peak of 50 kt on Saturday, followed by gradual 
weakening through next week.  Deep convection should be stripped 
away by Tuesday and Joyce is expected to become a remnant low 
at that point before opening into a trough.  However, the GFS 
suggests this could happen even sooner.

The storm is moving northwestward at 11 kt.  A weak mid-level ridge 
centered over the eastern Atlantic Ocean is expected to steer Joyce 
generally northwestward for the next day or so, followed by a 
gradual turn to the north-northwest and north with a slowing forward 
speed.  Model guidance is in relatively good agreement about this 
evolution and the NHC track forecast follows the various simple and 
corrected consensus aids.


FORECAST POSITIONS AND MAX WINDS

INIT  27/1500Z 18.1N  42.9W   35 KT  40 MPH
12H  28/0000Z 18.8N  44.3W   40 KT  45 MPH
24H  28/1200Z 19.4N  46.1W   50 KT  60 MPH
36H  29/0000Z 19.8N  47.7W   45 KT  50 MPH
48H  29/1200Z 20.7N  48.8W   40 KT  45 MPH
60H  30/0000Z 21.6N  49.4W   40 KT  45 MPH
72H  30/1200Z 22.6N  49.4W   35 KT  40 MPH
96H  01/1200Z 23.9N  48.8W   30 KT  35 MPH...POST-TROP/REMNT LOW
120H  02/1200Z...DISSIPATED

$$
Forecaster Bucci