ATL: LEE - Advisories

[cycloneye]

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.


KEY MESSAGES:

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.


FORECAST POSITIONS AND MAX WINDS

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

[cycloneye]

Post-Tropical Cyclone Lee Discussion Number 48
NWS National Hurricane Center Miami FL AL132023
500 AM AST Sun Sep 17 2023

Satellite imagery, surface observations and Canadian radar imagery
indicates that the center of Lee is near Prince Edward Island,
with most of the rain west of the center near New Brunswick.
Observations from the southern coast of Nova Scotia support lowering
the intensity to 45 kt on this advisory.

Lee has turned northeastward at about 19 kt. The system should
accelerate in this general direction as it interacts with the
stronger mid-latitude flow, but gradually weaken since it has lost
any baroclinic forcing. No significant changes were made to the
previous forecast, except to keep Lee a bit stronger in 36 hours
based on the global model wind forecasts.

KEY MESSAGES:

1. Tropical storm conditions and coastal flooding are occurring
across portions of Atlantic Canada. These winds could lead to
downed trees and power outages.

2. 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 Monday.


FORECAST POSITIONS AND MAX WINDS

INIT 17/0900Z 46.5N 63.7W 45 KT 50 MPH...POST-TROPICAL
12H 17/1800Z 48.4N 60.3W 40 KT 45 MPH...POST-TROP/EXTRATROP
24H 18/0600Z 51.2N 52.6W 35 KT 40 MPH...POST-TROP/EXTRATROP
36H 18/1800Z 53.5N 40.0W 35 KT 40 MPH...POST-TROP/EXTRATROP
48H 19/0600Z...DISSIPATED

$$
Forecaster Blake

[cycloneye]

Post-Tropical Cyclone Lee Discussion Number 49
NWS National Hurricane Center Miami FL AL132023
1100 AM AST Sun Sep 17 2023

Environment Canada has discontinued all Tropical Storm Warnings.
Post-Tropical Lee is moving toward the northeast and will likely
pass over Newfoundland later today. The cyclone should accelerate
east-northeastward and merge with a large extratropical low over
the North Atlantic in a couple of days.

This is the last advisory from the National Hurricane Center on
Lee. Additional information on this system can be found in High
Seas Forecasts issued by the National Weather Service, under AWIPS
header NFDHSFAT1, WMO header FZNT01 KWBC, and online at
ocean.weather.gov/shtml/NFDHSFAT1.php

KEY MESSAGES:

1. Gusty conditions will continue over portions of Atlantic Canada
today.

2. 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 Monday.


FORECAST POSITIONS AND MAX WINDS

INIT 17/1500Z 48.0N 62.0W 40 KT 45 MPH...POST-TROP/EXTRATROP
12H 18/0000Z 50.0N 56.8W 40 KT 45 MPH...POST-TROP/EXTRATROP
24H 18/1200Z 52.7N 47.3W 35 KT 40 MPH...POST-TROP/EXTRATROP
36H 19/0000Z 54.0N 34.0W 35 KT 40 MPH...POST-TROP/EXTRATROP
48H 19/1200Z...DISSIPATED

$$
Forecaster Pasch