Post-Tropical Cyclone Lee Forecast Discussion Number 47

By | September 17, 2023

WTNT43 KNHC 170242

Post-Tropical Cyclone Lee Discussion Number  47
NWS National Hurricane Center Miami FL       AL132023
1100 PM AST Sat Sep 16 2023

Satellite imagery, surface observations and Canadian radar imagery 
indicates that the center of Lee is over the Bay of Fundy, near the 
coast of New Brunswick. Rain bands continue to spread across 
portions of far eastern Maine and New Brunswick this evening. Drier 
air is wrapping into the system and has eroded most of the 
convection on the southern and eastern side of the circulation. 
Recent observations and a recent partial ASCAT pass support an 
intensity of 50 kt for this advisory.

The forward motion of Lee is slower than earlier today, as the 
system has stated to make a northeastward turn . This northeastward 
motion with an increase in forward speed is expected late tonight 
and Sunday, as the system moves across the Canadian Maritimes. The 
NHC forecast track is very similar to the previous forecast.

Strong wind shear, dry air, and land interaction should cause
steady weakening over the next day or so as Lee spins down.  The
global models are in agreement that Lee should dissipate on Monday,
and no real changes were made to the NHC intensity forecast.


1. Tropical storm conditions and coastal flooding are occurring
across portions of Atlantic Canada, and will continue to spread
northward within the Tropical Storm Warning areas. The strong winds
are leading to downed trees and power outages.

2. Any additional rainfall from Lee may produce localized urban and 
small stream flooding in portions of eastern Maine and portions of  
New Brunswick and Nova Scotia.

3. Dangerous surf and life-threatening rip currents will continue
to affect the U.S. East Coast, Atlantic Canada, Bermuda, the
Bahamas, the Turks and Caicos Islands, Hispaniola,  and Puerto
Rico through Sunday.


INIT  17/0300Z 45.3N  65.5W   50 KT  60 MPH...POST-TROPICAL
 12H  17/1200Z 47.2N  63.2W   45 KT  50 MPH...POST-TROP/EXTRATROP
 24H  18/0000Z 50.1N  57.1W   35 KT  40 MPH...POST-TROP/EXTRATROP
 36H  18/1200Z 52.5N  48.4W   30 KT  35 MPH...POST-TROP/EXTRATROP
 48H  19/0000Z...DISSIPATED

Forecaster Kelly/Brown

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