Official Discussion issued by the National Hurricane Center

Lee (AL132023) DATA RELEASED: 9/6/2023 9:00:00 PM UTC

Copy of official data

Hurricane Lee Discussion Number   6
NWS National Hurricane Center Miami FL       AL132023
500 PM AST Wed Sep 06 2023

Lee has continued to quickly organize today. Convective banding,
especially over the eastern semicircle of the storm, has increased
since this morning.  The center is embedded within a small central
dense overcast, and earlier this afternoon there was a hint of a 
ragged eye in visible imagery.  Although subjective Dvorak 
intensity estimates from SAB and TAFB were still T3.5 (55 kt) and 
most of the objective estimate are slightly below hurricane 
strength, the initial intensity has been increased to 65 kt based 
on the continued improvement in organization this afternoon, and 
the presence of a mid-level eye in a recent SSMIS microwave 
overpass. Lee becomes the fourth hurricane of the 2023 Atlantic 
hurricane season. 

Recent satellite fixes suggest that Lee took a northwestward jog 
this afternoon, however the longer-term motion is still 
west-northwestward at about 12 kt.  A mid-level ridge located 
to the north of Lee should continue to steer the cyclone on a
west-northwestward heading through the weekend.  Near the end of
the forecast period, Lee will be approaching the western periphery
of the ridge and the forward motion of the cyclone is likely to 
slow at that time.  The dynamical model guidance continues to
indicate that the core of Lee will pass to the north of the
northern Leeward Islands, however interests in those islands
should continue to monitor the latest forecasts as the typical
three-day NHC track error is about 90 n mi.  The NHC track 
forecast is again along the southern side of the guidance 
envelope, between the faster and farther south HFIP corrected 
consensus model, and the TVCA multi-model consensus aid.  The 
updated track foreast is slightly north of the previous advisory 
primarily due to the more northward initial position, and it is a 
little slower than the previous forecast to be closer to the 
latest consensus aids. 

The light to moderate east-northeasterly shear over Lee is forecast 
to decrease overnight, and that along with warm SSTs and a moist 
atmosphere along the forecast track should allow for additional 
intensification. With the small inner core seen in microwave 
imagery and favorable environmental conditions, a period of rapid 
strengthening is a distinct possibility within the next day or two.  
Although the exact timing of any rapid strengthening is tricky to 
anticipate, the official forecast calls for a substantial 65-kt 
increase in strength during the next 72 hours.  This is similar to 
the previous forecast, and is near the upper end of the intensity 
guidance.  By later in the weekend, hard-to-predict eyewall 
replacement cycles could cause some fluctuations in intensity.


1. Lee is forecast to become a major hurricane by early Saturday and
could bring impacts to the northern Leeward Islands this weekend.
While it is too soon to determine the location and magnitude of
these possible impacts, interests in this area should monitor the
progress of Lee and further updates to the forecast.

2. Swells generated by Lee are expected to reach portions of the
Lesser Antilles on Friday, and the British and U.S. Virgin Islands 
and Puerto Rico this weekend.  These swells are likely to cause
life-threatening surf and rip current conditions.


INIT  06/2100Z 14.9N  46.4W   65 KT  75 MPH
12H  07/0600Z 15.6N  48.2W   75 KT  85 MPH
24H  07/1800Z 16.5N  50.6W   85 KT 100 MPH
36H  08/0600Z 17.5N  53.0W   95 KT 110 MPH
48H  08/1800Z 18.6N  55.3W  110 KT 125 MPH
60H  09/0600Z 19.6N  57.5W  120 KT 140 MPH
72H  09/1800Z 20.4N  59.4W  130 KT 150 MPH
96H  10/1800Z 21.9N  62.9W  130 KT 150 MPH
120H  11/1800Z 23.0N  65.2W  125 KT 145 MPH

Forecaster Brown