Official Discussion issued by the National Hurricane Center

Rene (AL182020) DATA RELEASED: 9/12/2020 3:00:00 AM UTC

Copy of official data

Tropical Storm Rene Discussion Number  20
NWS National Hurricane Center Miami FL       AL182020
1100 PM AST Fri Sep 11 2020

Deep convection has persisted near the center of Rene since this
afternoon and a couple of earlier microwave overpasses suggest that
there has been an increase in banding over the southwestern portion
of the circulation. Despite what appears to be an increase in
organization, recent ASCAT data indicated that this has not
translated into an increase in intensity.  The scatterometer data
still supports an initial wind speed of 35 kt.  Environmental
conditions are forecast to generally be conducive for some
strengthening over the next 12-24 hours, however with Rene
continuing to struggle to intensify the NHC wind speed prediction
has again been reduced during the that time.  By 36-48 hours, Rene
is expected to move beneath an area of strong upper-level
west-northwesterly flow, and this increase in shear is expected to
cause weakening.  The ECMWF and GFS models significantly weaken
Rene after 72 hours, with the ECMWF showing dissipation before the
end of the forecast period.  For now, the official forecast calls
for Rene to weaken to a tropical depression by day 4, but it is
possible that the system will degenerate into a trough of low
pressure before day 5.

Rene is moving west-northwestward or 295/12 kt.  The cyclone should
turn toward the northwest as it moves around the western portion of
a mid-level ridge over the eastern Atlantic. In a couple of days, a
mid-level high is predicted to build to the northwest of Rene,
which should cause the cyclone to slow down and turn westward, and
then west-southwestward later in the forecast period. The track
guidance is in fairly good agreement and the various consensus aids
remained close to the previous official forecast.  Therefore, the
new NHC forecast is essentially an update of the previous advisory.


INIT  12/0300Z 21.4N  42.4W   35 KT  40 MPH
12H  12/1200Z 22.4N  44.0W   35 KT  40 MPH
24H  13/0000Z 24.1N  45.8W   40 KT  45 MPH
36H  13/1200Z 25.7N  47.0W   40 KT  45 MPH
48H  14/0000Z 26.8N  47.6W   40 KT  45 MPH
60H  14/1200Z 27.1N  47.8W   35 KT  40 MPH
72H  15/0000Z 26.8N  48.4W   35 KT  40 MPH
96H  16/0000Z 25.9N  50.9W   30 KT  35 MPH
120H  17/0000Z 24.8N  54.0W   30 KT  35 MPH

Forecaster Brown