Official Discussion issued by the National Hurricane Center

Rene (AL182020) DATA RELEASED: 9/8/2020 8:00:00 AM UTC

Copy of official data

Tropical Storm Rene Discussion Number   5
NWS National Hurricane Center Miami FL       AL182020
800 AM CVT Tue Sep 08 2020

While Rene continues to have a well-defined circulation, satellite 
imagery indicates that the associated convection remains poorly 
organized.  Various subjective and objective satellite intensity 
estimates are in the 30-35 kt range.  Based on these, along with a 
28 kt observation from Sal/GVAC, the initial intensity remains a 
possible generous 35 kt.

The initial motion is westward or 280/13 kt.  There is no change 
in the track forecast philosophy, as a westward motion is expected 
today, followed by a west-northwestward motion through Thursday as 
Rene rounds the southwestern periphery of a deep-layer subtropical 
ridge. On days 4 and 5, the cyclone is forecast to move more slowly 
northwestward to north-northwestward through a weakness in the 
aforementioned ridge.  The track guidance has shifted a little 
eastward after 72 h, and the new track forecast is also nudged 
eastward during that time.  Other than that, the new forecast track 
is similar to the previous track.

It is unclear why the convection is currently so poorly organized, 
although land interaction with the Cabo Verde Islands is a 
possibility.  Conditions generally appear favorable for 
strengthening during the next three days or so, and much of the 
intensity guidance forecasts Rene to become a hurricane in 2-3 days 
time even though the water temperatures gradually decrease along 
the forecast track.  After 72 h, Rene is expected to reach both 
warmer water and strong westerly shear, with the latter expected to 
cause the storm to weaken.  The new intensity forecast has only 
minor tweaks from the previous forecast and follows the trend of 
the intensity guidance. 

Key Messages:

1. Rene is expected to produce tropical storm conditions across
portions of the Cabo Verde Islands today.  A Tropical Storm Warning 
is in effect for those islands.

2. Rene will bring locally heavy rainfall to portions of the Cabo
Verde Islands today.


INIT  08/0900Z 16.4N  24.9W   35 KT  40 MPH
12H  08/1800Z 16.7N  26.9W   35 KT  40 MPH
24H  09/0600Z 17.1N  29.5W   45 KT  50 MPH
36H  09/1800Z 17.9N  32.1W   55 KT  65 MPH
48H  10/0600Z 18.8N  34.7W   65 KT  75 MPH
60H  10/1800Z 19.8N  37.1W   70 KT  80 MPH
72H  11/0600Z 21.0N  39.0W   70 KT  80 MPH
96H  12/0600Z 24.5N  42.0W   65 KT  75 MPH
120H  13/0600Z 28.6N  42.9W   55 KT  65 MPH

Forecaster Beven