Official Discussion issued by the National Hurricane Center

Philippe (AL172023) DATA RELEASED: 9/26/2023 9:00:00 PM UTC

Copy of official data

Tropical Storm Philippe Discussion Number  14
NWS National Hurricane Center Miami FL       AL172023
500 PM AST Tue Sep 26 2023

Philippe remains a strongly sheared and poorly organized tropical
storm.  The low-level center continues to pull away from the
associated deep convection and is now located about 100 n
mi west of a small area of thunderstorms.  In fact, the system
barely meets the convective criteria of a tropical cyclone.
Despite the ragged satellite appearance, the initial intensity is
held at 40 kt based on partial ASCAT data that showed a patch of
tropical-storm-force winds well east of the center earlier today.

The models are in agreement that strong shear will continue to
affect Philippe during the next several days, which in combination
with dry air entrainment should cause gradual weakening despite
its passage over warm SSTs.  Simulated satellite images from the
GFS and ECMWF models show Philippe losing all of its deep
convection in a few days, and the NHC forecast continues to show 
Philippe becoming a remnant low by day 4.  However, it would not be 
surprising if the system becomes a remnant low or opens into a 
trough sooner than that.

Philippe has not gained any latitude since this time yesterday and 
all of the models have had a notable north bias during that time 
period.  Based on recent trends and since Philippe is expected to 
stay a decoupled and weak system moving in the low-level flow, 
another shift to the left has been made in this forecast.  This 
prediction lies near the southern side of the model guidance 


INIT  26/2100Z 17.1N  51.3W   40 KT  45 MPH
12H  27/0600Z 17.3N  52.7W   40 KT  45 MPH
24H  27/1800Z 18.4N  54.5W   35 KT  40 MPH
36H  28/0600Z 19.2N  56.1W   35 KT  40 MPH
48H  28/1800Z 19.7N  57.9W   35 KT  40 MPH
60H  29/0600Z 20.0N  59.3W   30 KT  35 MPH
72H  29/1800Z 20.1N  61.0W   30 KT  35 MPH
96H  30/1800Z 20.2N  64.0W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  01/1800Z 20.3N  67.8W   25 KT  30 MPH...POST-TROP/REMNT LOW

Forecaster Cangialosi