Official Discussion issued by the National Hurricane Center

Philippe (AL172023) DATA RELEASED: 10/5/2023 3:00:00 AM UTC

Copy of official data

Tropical Storm Philippe Discussion Number  47
NWS National Hurricane Center Miami FL       AL172023
1100 PM AST Wed Oct 04 2023

Philippe has generally changed little during the past several hours. 
The storm still resembles an elongated trough in satellite images 
with a north-south oriented area of deep convection extending a 
couple of hundred north and several hundred miles south of the 
center.  Areas of heavy rain continue to linger near Puerto Rico and 
the Virgin Islands.  Since the system appears to be steady in 
strength, the initial intensity is held at 35 kt based on the 
earlier aicraft data.  This wind speed estimate is also in line with 
the latest satellite intensity estimates.

The storm is moving northward at 11 kt in the flow between a ridge 
over the central Atlantic and a mid- to upper-level low off the 
Florida coast.  This northward motion with an increase in forward 
speed is expected during the next few days, taking the center 
of the system across Bermuda in 36-48 hours.  Philippe will likely 
turn northwestward into Maine and Atlantic Canada this weekend when 
another trough cuts off over the northeastern U.S.  The NHC track 
forecast is similar to the previous one and near the middle of the 
guidance envelope.

Nearly all of the models show slow strengthening during the next 2 
or 3 days, which seems to be due to baroclinic influences from the 
trough/low currently east of Florida.  The mid- to upper-level 
trough/low will likely merge with Philippe in 48-60 hours, which 
should cause the system to develop frontal features and become 
extratropical after it passes Bermuda.  The post-tropical cyclone 
is expected to weaken once it moves inland over Maine and Atlantic 
Canada.  The NHC intensity forecast also lies near the middle of 
the guidance envelope.


1. Tropical storm conditions are expected on Bermuda beginning
Thursday night, and a Tropical Storm Warning is in effect. Heavy 
rainfall will begin to affect the island on Thursday.

2. Philippe is likely to move over portions of Atlantic Canada and
eastern New England, likely as a post-tropical cyclone, this
weekend.  Regardless of Philippe's intensity or structure, interests
in those areas should monitor the storm's progress and be prepared
for the possibility of strong winds and heavy rainfall.


INIT  05/0300Z 23.8N  66.1W   35 KT  40 MPH
12H  05/1200Z 25.4N  66.3W   35 KT  40 MPH
24H  06/0000Z 28.4N  66.0W   40 KT  45 MPH
36H  06/1200Z 31.9N  65.9W   40 KT  45 MPH
48H  07/0000Z 35.3N  66.4W   45 KT  50 MPH
60H  07/1200Z 39.0N  66.7W   50 KT  60 MPH
72H  08/0000Z 43.3N  67.1W   50 KT  60 MPH...POST-TROP/EXTRATROP
96H  09/0000Z 51.6N  73.2W   35 KT  40 MPH...POST-TROP/EXTRATROP
120H  10/0000Z...DISSIPATED

Forecaster Cangialosi