Official Discussion issued by the National Hurricane Center

Lee (AL132023) DATA RELEASED: 9/10/2023 9:00:00 PM UTC

Copy of official data

Hurricane Lee Discussion Number  22
NWS National Hurricane Center Miami FL       AL132023
500 PM AST Sun Sep 10 2023

Lee has continued to become better organized today. The eye has 
become more apparent in both infrared and visible satellite
imagery this afternoon, and reconnaissance aircraft reports 
indicate that the eye has contracted today.  An Air Force Reserve 
Hurricane Hunter aircraft that is currently investigating Lee has 
measured peak 700-mb flight-level winds of 112 kt and SFMR winds of 
106 kt. Near the conclusion of the earlier NOAA P-3 aircraft 
mission an eyewall dropsonde measured mean boundary layer winds in 
the lowest 150 m of the sonde of 117 kt, which supported surface 
winds of around 100 kt.  Based on the improved satellite 
presentation and the recent SFMR wind report, Lee's initial 
intensity has been raised to 105 kt.

As mentioned this morning, the vertical wind shear over Lee appears
to have decreased as the upper-level outflow has become better
established over the southern and southwestern portions of the
storm.  Some further reduction in shear is anticipated during the
next day or so, and Lee is expected to restrengthen during that
time.  The NHC intensity prediction calls for steady intensification
during the next 24 hours or so, and Lee is forecast regain category
4 status tonight or early Monday.  After that time, the slow 
motion of the hurricane could cause the water beneath the hurricane 
to cool due to upwelling, which is likely to cause Lee's intensity 
to plateau or weaken slight during the middle portion of the 
forecast period.  By days 4 and 5, increasing southwesterly shear 
is likely to cause weakening, however Lee's wind field is expected 
to expand by that time, and Lee is forecast to remain a strong 
hurricane through most of this week.

Lee is moving west-northwestward or 300 at 7 kt. Lee's is expected 
to move slowly northwestward during the next couple of days as its 
forward progress is impeded by a high pressure ridge located to the 
northwest of the storm.  By Wednesday, a mid-latitude trough moving 
across the Great Lakes region and into the northeastern United 
States should weaken the ridge and allow Lee to turn northward.  The 
ECMWF model has trended faster with the northward progression of Lee 
late in the period and there is a little less spread in the guidance 
at day 5.  The updated NHC track forecast is very similar the 
previous track, but has trended a bit faster later in the period.  
Users should be reminded to not focus on the exact forecast track, 
especially at the longer range, as the average day 4 and 5 track 
errors are about 145 and 200 miles, respectively. 


1. Dangerous surf and life-threatening rip currents will affect
portions of the northern Leeward Islands, the Virgin Islands, Puerto 
Rico, Hispaniola, the Turks and Caicos Islands, the Bahamas, and 
Bermuda through much of this week.

2. Lee could bring wind, rainfall, and high surf impacts to
Bermuda later this week.  Although it is too soon to determine the
specific timing and level of those impacts, interests on Bermuda
should monitor the latest forecasts for Lee.

3. It remains too soon to know what level of impacts, if any,
Lee might have along the U.S. East Coast and Atlantic Canada late
this week, especially since the hurricane is expected to slow
down considerably over the southwestern Atlantic.  Regardless,
dangerous surf and rip currents are expected along most of the U.S.
East Coast this week as Lee grows in size. Users should continue to
monitor updates to the forecast of Lee during the next several days.


INIT  10/2100Z 22.1N  61.7W  105 KT 120 MPH
12H  11/0600Z 22.7N  62.7W  115 KT 130 MPH
24H  11/1800Z 23.3N  63.9W  120 KT 140 MPH
36H  12/0600Z 23.8N  65.1W  120 KT 140 MPH
48H  12/1800Z 24.2N  66.2W  115 KT 130 MPH
60H  13/0600Z 24.7N  67.0W  105 KT 120 MPH
72H  13/1800Z 25.6N  67.6W  100 KT 115 MPH
96H  14/1800Z 28.9N  68.0W   90 KT 105 MPH
120H  15/1800Z 33.6N  67.4W   80 KT  90 MPH

Forecaster Brown