Official Discussion issued by the National Hurricane Center

Philippe (AL172023) DATA RELEASED: 10/1/2023 9:00:00 PM UTC

Copy of official data

Tropical Storm Philippe Discussion Number  34
NWS National Hurricane Center Miami FL       AL172023
500 PM AST Sun Oct 01 2023

The structure of Philippe has not changed much since this morning. A 
large area of deep convection remains in the southeastern quadrant 
of the cyclone, with a small burst near the center.  The initial 
wind speed is held at 45 kt, per the latest satellite 
classifications, and an Air Force Reserve Hurricane Hunter aircraft 
is scheduled to be inside the storm tonight.

The southward progress of Philippe has thankfully stopped today,
and recent fixes show it moving between west-northwest and
northwest at about 6 kt.  A building ridge well to the northeast
should steer the storm generally northwestward tonight and Monday,
with a turn to the north forecast on Tuesday while the system moves
around the western periphery of the ridge.  Eventually a faster 
north-northeastward motion is anticipated at long range as the storm 
enters the mid-latitudes.  While the track forecast has been 
adjusted a bit to the east, this should not be interpreted as the 
end of any threat to the Leeward Islands with still some models 
near those islands.  Notably, a very strong rain band on the 
southern side of Philippe will be very close to moving over the 
northern Leeward Islands, and it could turn out that rainfall and 
flooding would be the main hazard of the storm.

There's been no change to the intensity forecast reasoning from the
last cycle, with strong shear near Philippe expected to limit
intensification during the next couple of days.  There remains a
decent chance that the shear could relax by the middle of the week,
allowing Philippe to become a hurricane after it recurves into the
subtropical central Atlantic.  Guidance has been inconsistent at 
long range with the storm, so the best course of action seems to 
be to hold the forecast steady to see if any notable trends emerge.


1. Tropical storm conditions are possible across portions of the
northern Leeward Islands Monday and Monday night while Philippe
passes near or just northeast of the area, and a Tropical Storm
Watch is in effect for Antigua and Barbuda.  Interests elsewhere
in the northern Leeward Islands should continue to monitor this
system as additional watches or warnings could be required later
today or tonight.

2. Heavy rainfall from Philippe could produce isolated to scattered
flash flooding, particularly across Barbuda and Antigua, through


INIT  01/2100Z 16.4N  59.0W   45 KT  50 MPH
12H  02/0600Z 17.0N  59.9W   45 KT  50 MPH
24H  02/1800Z 17.7N  60.8W   45 KT  50 MPH
36H  03/0600Z 18.7N  61.6W   50 KT  60 MPH
48H  03/1800Z 19.9N  62.0W   50 KT  60 MPH
60H  04/0600Z 21.4N  62.2W   50 KT  60 MPH
72H  04/1800Z 23.1N  62.2W   55 KT  65 MPH
96H  05/1800Z 26.9N  61.1W   65 KT  75 MPH
120H  06/1800Z 30.0N  58.0W   75 KT  85 MPH

Forecaster Blake