Official Discussion issued by the National Hurricane Center

Rene (AL182020) DATA RELEASED: 9/10/2020 9:00:00 AM UTC

Copy of official data

Tropical Storm Rene Discussion Number  13
NWS National Hurricane Center Miami FL       AL182020
500 AM AST Thu Sep 10 2020

Several recent microwave overpasses indicate that Rene continues to 
be affected by easterly shear, with the low-level center located 
near the eastern edge of the ongoing bursting convection.  Various 
subjective and objective satellite intensity estimates are in the 
35-45 kt range and have changed little since the last advisory.  
Based on that, the initial intensity remains 35 kt.

The initial motion is west-northwestward or 285/9 kt.  There is no 
change in the overall track forecast philosophy.  Rene should move 
generally west-northwestward for the next couple of days, followed 
by a turn toward the northwest into a weakness in the subtropical 
ridge partly caused by Tropical Storm Paulette.  Late in the 
forecast period, the track forecast becomes more problematic due to 
uncertainties in how much ridging will build north of Rene and how 
close it will be to the larger Paulette.  The track guidance during 
this time shows increasing spread and some westward shift from the 
previous advisory.  The new NHC forecast track is similar to the 
previous track through 72 h, then it lies to the left of the 
previous track at 96 and 120 h.  However, at these times, it lies 
to the right of the various consensus models.

The shear should gradually diminish during the next 48-60 h, and 
this should allow Rene to strengthen to or near hurricane strength. 
After that time, strong west-northwesterly shear is expected to 
cause gradual weakening despite the cyclone moving over increasing 
sea surface temperatures.  The new official intensity forecast is 
unchanged from the previous forecast.  It lies near the various 
intensity consensus models through 72 h, but is weaker than those 
models at 96 and 120 h.


INIT  10/0900Z 18.2N  34.8W   35 KT  40 MPH
12H  10/1800Z 18.6N  36.2W   40 KT  45 MPH
24H  11/0600Z 19.1N  38.1W   45 KT  50 MPH
36H  11/1800Z 19.8N  40.2W   50 KT  60 MPH
48H  12/0600Z 21.0N  42.2W   60 KT  70 MPH
60H  12/1800Z 22.4N  44.1W   65 KT  75 MPH
72H  13/0600Z 24.1N  45.7W   60 KT  70 MPH
96H  14/0600Z 27.0N  47.5W   50 KT  60 MPH
120H  15/0600Z 28.6N  49.0W   40 KT  45 MPH

Forecaster Beven