2023 Hurricane Season Discussion

General Weather Discussions and Analysis
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tireman4
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ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM

Tropical Storm Margot Discussion Number 17
NWS National Hurricane Center Miami FL AL142023
Issued by the NWS Weather Prediction Center College Park MD
300 PM GMT Mon Sep 11 2023

Satellite images indicate that Margot is strengthening. A ragged
eye has emerged from the central dense overcast pattern, although
it is open on the east side. Additionally, overnight microwave
data showed the eye pattern on numerous passes, suggesting this is
a real eye feature. With the improvement in the satellite
presentation, the initial wind speed is set to 60 kt, closest to
the D-MINT intensity estimate from UW-CIMSS, but below recent
Dvorak DT estimates of 65 kt.

Margot is moving northward at about 9 kt, and that general motion
should continue for the next few days, with a north-northwest bend
expected by midweek as ridging builds to the east of the storm. A
large mid-latitude ridge is forecast to block Margot's path after
that time, causing the cyclone to basically stall by the weekend.
Guidance is in very good agreement for the first few days, then the
uncertainty grows in unsteady steering currents beneath the ridge,
with aids fanning out in all directions. The new forecast is
similar to the previous one, showing little motion at days 4-5 as a
compromise between the various divergent model solutions.

The storm has a chance to strengthen further over the next couple
of days while it moves over relatively warm waters up to 28 deg C
and in lessening shear. In a few days, an increase in shear and
dry-air entrainment should gradually weaken Margot. This is an
interesting forecast because the dynamical model guidance is well
below the statistical guidance, despite a seemingly conducive
environment for intensification. The new NHC forecast leans
closer to the statistical models, adjusted a bit higher than the
last NHC intensity prediction, similar to the Florida State
Superensemble and NOAA corrected-consensus models.



FORECAST POSITIONS AND MAX WINDS

INIT 11/1500Z 26.1N 40.0W 60 KT 70 MPH
12H 12/0000Z 27.6N 40.0W 65 KT 75 MPH
24H 12/1200Z 29.8N 40.0W 75 KT 85 MPH
36H 13/0000Z 31.9N 40.5W 80 KT 90 MPH
48H 13/1200Z 33.6N 41.4W 80 KT 90 MPH
60H 14/0000Z 34.7N 41.9W 75 KT 85 MPH
72H 14/1200Z 35.8N 41.8W 70 KT 80 MPH
96H 15/1200Z 37.1N 40.9W 65 KT 75 MPH
120H 16/1200Z 37.0N 41.0W 55 KT 65 MPH

$$
Forecaster Blake/Taylor

NNNN
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URNT12 KNHC 111832
VORTEX DATA MESSAGE AL132023
A. 11/18:01:30Z
B. 23.50 deg N 063.93 deg W
C. 700 mb 2662 m
D. 949 mb
E. 175 deg 9 kt
F. OPEN SE
G. CO22-68
H. 87 kt
I. 330 deg 35 nm 17:50:00Z
J. 063 deg 104 kt
K. 329 deg 38 nm 17:49:00Z
L. 81 kt
M. 137 deg 33 nm 18:11:00Z
N. 231 deg 96 kt
O. 136 deg 37 nm 18:12:00Z
P. 8 C / 3052 m
Q. 17 C / 3056 m
R. NA / NA
S. 12345 / 07
T. 0.02 / 2 nm
U. AF309 1713A LEE OB 06
MAX FL WIND 104 KT 329 / 38 NM 17:49:00Z
OUTER EYEWALL CLOSED
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676
WTNT43 KNHC 120851
TCDAT3

Hurricane Lee Discussion Number 28
NWS National Hurricane Center Miami FL AL132023
500 AM AST Tue Sep 12 2023

Lee continues to exhibit a concentric eyewall structure in
conventional satellite imagery. This has been confirmed by the Air
Force Reserve Hurricane Hunters that investigated Lee early this
morning, and they reported the outer eyewall had a large diameter of
80 n mi. The maximum 700-mb flight-level wind measured by the
aircraft was 112 kt in the northeast quadrant, while the SFMR winds
peaked around 90 kt. Although the satellite intensity estimates have
fallen a bit this morning, the reduced flight-level winds support
holding the initial intensity at 100 kt for this advisory. The
minimum pressure of Lee remains 948 mb based on dropsonde data.

Lee is still moving slowly west-northwestward (290/6 kt), with
mid-level ridging established to the north and west of the
hurricane. This steering pattern is expected to change during the
next couple of days as a deep-layer trough moves across the eastern
United States and produces a weakness in this ridge. As a result,
Lee is forecast to turn northward and gradually accelerate during
the middle and latter parts of this week. The track guidance
envelope shows little cross-track spread during the first 3 days of
the forecast period, and this portion of the NHC forecast is fairly
similar to the previous one. While the core of the hurricane is
forecast to pass west of Bermuda, the large wind field of the storm
is likely to bring wind impacts to the island later this week, and
tropical storm watches could be required later today. At days 4-5,
there has been a slight westward shift in the guidance envelope, and
accordingly the NHC track forecast was nudged in that direction
toward the HCCA and TVCA aids.

Based on Lee's current satellite structure, as well as its slow
forward motion and large wind field, little near-term strengthening
is expected. Going forward, the large hurricane appears likely to
begin upwelling cooler waters along its path, and in a few days it
will encounter the cool wake left behind by recent western Atlantic
hurricanes. Thus, gradual weakening is forecast through midweek.
Later, the aforementioned trough is expected to produce stronger
deep-layer shear over Lee, and the hurricane is forecast to move
over significantly cooler waters as it passes north of the Gulf
Stream. As a result, more significant weakening is shown at days
4-5, along with completion of its extratropical transition. Despite
the weakening that is forecast, keep in mind that the expanding wind
field of Lee will produce impacts well away from the storm center.


KEY MESSAGES:

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,
Bermuda, and most of the U.S East Coast through much of the week.

2. There is an increasing risk of strong winds, rainfall, and high
surf impacts to Bermuda later this week, and tropical storm watches
could be required for the island later today.

3. It remains too soon to know what level of additional impacts Lee
might have along the Northeastern U.S. coast and Atlantic Canada
late this week and this weekend. However, since wind and rainfall
hazards will extend well away from the center as Lee grows in size,
users should continue to monitor updates to Lee's forecast during
the next several days.


FORECAST POSITIONS AND MAX WINDS

INIT 12/0900Z 24.0N 65.4W 100 KT 115 MPH
12H 12/1800Z 24.4N 66.2W 100 KT 115 MPH
24H 13/0600Z 25.3N 67.0W 100 KT 115 MPH
36H 13/1800Z 26.6N 67.5W 95 KT 110 MPH
48H 14/0600Z 28.3N 67.9W 90 KT 105 MPH
60H 14/1800Z 30.4N 68.0W 85 KT 100 MPH
72H 15/0600Z 32.9N 67.6W 80 KT 90 MPH
96H 16/0600Z 39.0N 66.7W 70 KT 80 MPH
120H 17/0600Z 44.5N 66.0W 50 KT 60 MPH...POST-TROP/EXTRATROP

$$
Forecaster Reinhart
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WTNT44 KNHC 120847
TCDAT4

Hurricane Margot Discussion Number 20
NWS National Hurricane Center Miami FL AL142023
900 AM GMT Tue Sep 12 2023

Margot's eye became obscured in infrared satellite imagery a couple
of hours ago, but the hurricane still has a well-defined Central
Dense Overcast surrounded by convective banding features. A dry
slot has become entrained into the eastern part of the circulation,
between the CDO and the outermost banding. Based on consensus
Dvorak estimates of T4.5 from TAFB and SAB, the initial intensity
is raised to 75 kt.

Margot is moving northward (360/11 kt) along the western periphery
of a mid-level ridge emanating out of western Africa, and this
steering mechanism should keep the hurricane on a general
northward or north-northwestward trajectory for the next few
days. A blocking ridge is forecast to form in 2-3 days over the
north Atlantic, which is likely to cause Margot to slow down during
the middle to latter part of the forecast period. However, the
ridge may be relatively progressive, and by day 5 many of the track
models show the storm picking up some speed again once the ridge
gets out of the way. The most notable change in the NHC track
forecast is that it's faster than the previous prediction on days 4
and 5 to better align with the latest guidance.

The hurricane is currently within a strongly diffluent environment
to the east of an upper-level trough, but the environment is
forecast to evolve to an anticyclone aloft and low shear within the
next 12 hours. Continued strengthening is therefore likely, but
any intensification trend could be halted soon after 24 hours when
the hurricane slows down and potentially upwells cooler waters.
The NHC intensity forecast is above the intensity consensus during
the first day or two and is closest to the statistical-dynamical
guidance. Weakening is likely to occur after 48 hours due to
cooler waters and an increase in deep-layer shear.


FORECAST POSITIONS AND MAX WINDS

INIT 12/0900Z 29.3N 39.5W 75 KT 85 MPH
12H 12/1800Z 30.9N 39.9W 80 KT 90 MPH
24H 13/0600Z 32.7N 40.8W 85 KT 100 MPH
36H 13/1800Z 34.0N 41.7W 85 KT 100 MPH
48H 14/0600Z 35.0N 42.1W 85 KT 100 MPH
60H 14/1800Z 36.0N 41.9W 80 KT 90 MPH
72H 15/0600Z 36.9N 41.6W 75 KT 85 MPH
96H 16/0600Z 38.2N 42.6W 60 KT 70 MPH
120H 17/0600Z 40.4N 43.4W 50 KT 60 MPH

$$
Forecaster Berg
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Enough about Lee.. non-factor.
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tireman4
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tireman4 wrote: Tue Sep 12, 2023 11:32 am
snowman65 wrote: Tue Sep 12, 2023 9:10 am Enough about Lee.. non-factor.
Well, with all due respect, this 2023 Hurricane Discussion. Lee and Margot are hurricanes ( or tropical systems). Second, there are people on this forum that have loved ones in the area that Lee might come close to. Third, I appreciate your input, but this is an information board and information is being posted. If you have issues or concerns, please contact me by DM. :)!!!!!!!
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snowman65 may be a non factor to you, not to some folks thougb it isnt
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tireman4
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From Mr. 57..

HAFS A & B are trending farther east, taking Lee into New Brunswick at a faster pace. Let's see if the EC speeds it up at 12Z and catches the trof. It'll be transitioning to ET by the time it passes east of Cape Cod Saturday morning. Larger wind field, no core of intense winds. Big issue for southern New England will be the 30-40 mph wind. Trees have leaves on them this time or year, unlike when nor'easters produce this kind of wind. Also, the ground is saturated from recent rains, making trees more apt to fall.

P.S.
Yes, EC has a faster movement and takes the center inland into New Brunswick. However, by then, there won't be anything near the center to make landfall.
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tireman4 wrote: Tue Sep 12, 2023 11:35 am
tireman4 wrote: Tue Sep 12, 2023 11:32 am
snowman65 wrote: Tue Sep 12, 2023 9:10 am Enough about Lee.. non-factor.
Well, with all due respect, this 2023 Hurricane Discussion. Lee and Margot are hurricanes ( or tropical systems). Second, there are people on this forum that have loved ones in the area that Lee might come close to. Third, I appreciate your input, but this is an information board and information is being posted. If you have issues or concerns, please contact me by DM. :)!!!!!!!
Large windfield (500 miles) by the time Lee reaches east of Cape Cod.
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000
WTNT43 KNHC 130853
TCDAT3

Hurricane Lee Discussion Number 32
NWS National Hurricane Center Miami FL AL132023
500 AM AST Wed Sep 13 2023

Lee's structure is very gradually declining in organization. The
hurricane has a ragged but somewhat elliptical 25-30 n mi wide eye,
but deep convection has become eroded a bit within the western
semicircle, possibly due to some moderate westerly shear. In
addition, a 0607 UTC AMSR-2 microwave pass showed that the eyewall
was open on the southwest side at that time. Subjective and
objective satellite estimates range from 90-105 kt, so Lee's
initial intensity remains 100 kt for now.

The hurricane is very slowly making its turn around a west-central
Atlantic mid-level high, with its motion now northwestward at
325/5 kt. The track guidance is tightly clustered during the next
2 days or so, showing Lee turning and accelerating toward the
north-northwest and north between the high and a shortwave trough
swinging across the Great Lakes region. Lee's core is forecast to
pass west of Bermuda in 36-48 hours, but tropical storm conditions
are likely to begin there late tonight or early Thursday due to the
hurricane's large wind field. On days 3 and 4, Lee is expected to
maintain a general northward track offshore the northeastern U.S.
However, the global models are suggesting that the hurricane
will interact with a remnant mid-level trough over the mid-Atlantic
states, causing Lee to possibly bend just west of due north while
it moves across the Gulf of Maine. Under the assumption that the
global models will have a better handle on this mid-latitude
pattern as compared to the regional hurricane models, the NHC track
forecast is close to a consensus of the GFS and ECMWF models (GFEX)
on days 3, 4, and 5, and therefore ends up being a bit west and
then north of the previous prediction on those days.

A number of factors--including Lee's broad structure, increasing
shear, and potential upwelling of cooler waters--are likely to lead
to a very gradual decrease in the hurricane's maximum winds during
the next 3 days or so. In addition, Lee is likely to begin
extratropical transition in 2-3 days, with that process expected to
be complete just before the cyclone's center reaches the coast of
Maine, New Brunswick, or Nova Scotia in about 4 days. That said,
Lee's expected post-tropical transition will not diminish potential
wind, rain, and coastal flooding impacts in New England and Atlantic
Canada due to the system's broad wind field.

It should again be noted that the 34- and 50-kt wind speed
probabilities beyond 36 hours in the text and graphical products are
likely underestimating the risk of those winds occurring. This is
because the forecast wind field of Lee is considerably larger than
average compared to the wind field used to derive the wind speed
probability product.


KEY MESSAGES:

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,
Bermuda, and most of the U.S East Coast through much of the week.

2. Tropical storm conditions, heavy rainfall, and high surf are
expected to impact Bermuda beginning late tonight or early Thursday,
and a Tropical Storm Warning is in effect for the island.

3. There is an increasing risk of wind, coastal flooding, and rain
impacts from Lee in portions of New England and Atlantic Canada
beginning on Friday and continuing through the weekend. Watches may
be required for portions of these areas later today or tonight.
Due to Lee's large size, hazards will extend well away from the
center, and there will be little to no significance on exactly where
the center reaches the coast.


FORECAST POSITIONS AND MAX WINDS

INIT 13/0900Z 25.7N 67.1W 100 KT 115 MPH
12H 13/1800Z 26.6N 67.6W 95 KT 110 MPH
24H 14/0600Z 28.4N 68.1W 90 KT 105 MPH
36H 14/1800Z 30.5N 68.3W 85 KT 100 MPH
48H 15/0600Z 33.0N 68.0W 80 KT 90 MPH
60H 15/1800Z 36.1N 67.4W 75 KT 85 MPH
72H 16/0600Z 39.6N 67.3W 70 KT 80 MPH
96H 17/0600Z 45.2N 67.3W 50 KT 60 MPH...POST-TROP/INLAND
120H 18/0600Z 51.0N 61.4W 35 KT 40 MPH...POST-TROP/INLAND

$$
Forecaster Berg
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000
WTNT44 KNHC 130854
TCDAT4

Hurricane Margot Discussion Number 24
NWS National Hurricane Center Miami FL AL142023
900 AM GMT Wed Sep 13 2023

The eye of Margot has been obscured by clouds to varying degrees
overnight, but has begun to warm in the latest infrared satellite
images this morning. Recent AMSR2 microwave images reveal the
hurricane has a compact inner core, with a concentric outer ring of
convection that is broken to the northwest. Earlier scatterometer
data indicated a secondary wind maximum exists within this outer
band. The vortex is slightly tilted with height, as the mid-level
89-GHz eye lies to the southwest of the 37-GHz center. The
intensity for this advisory remains 75 kt based on consensus T4.5
Dvorak classifications from TAFB and SAB.

Margot has begun to slow down while moving northward (350/10 kt)
within the flow between a deep-layer ridge over the eastern Atlantic
and a narrow upper trough to its west. A general northward motion
should continue over the next day or so before the track forecast
becomes very challenging. Margot is forecast to become caught in
weak steering currents, with the global models showing a blocking
ridge developing to the north of the cyclone by late week into the
weekend. There are significant differences between the GFS and ECMWF
with regards to the strength and position of this ridge, which has
large implications in the longer-range track of Margot. Based on the
overall shift in the guidance suite this cycle, the latest NHC
forecast shows little net motion between 36-72 h as Margot meanders
over the central Atlantic. This is a fairly large departure from the
previous advisory, but better represents the latest consensus track
solutions. At days 4-5, most models (except for the ECMWF) show the
ridge sliding eastward, but overall track forecast confidence is
very low and larger future adjustments could be necessary.

It is possible that Margot is at or near its peak intensity. The
deep-layer shear is forecast to increase during the next 24 h, and
thereafter the coupled atmosphere-ocean models indicate the slow
motion of the storm is likely to result in upwelling of cooler
waters. In addition, the surrounding environment is expected to
become drier and more subsident by this weekend. The NHC intensity
forecast has been lowered from the previous one and shows steady
weakening beyond 36 h, in good agreement with the latest HCCA and
IVCN aids. Although this forecast keeps Margot a tropical cyclone
through day 5, simulated satellite imagery from the global models
suggests these environmental factors could cause the system to lose
organized convection and become post-tropical early next week.


FORECAST POSITIONS AND MAX WINDS

INIT 13/0900Z 33.6N 40.0W 75 KT 85 MPH
12H 13/1800Z 34.5N 40.5W 75 KT 85 MPH
24H 14/0600Z 35.6N 40.5W 70 KT 80 MPH
36H 14/1800Z 36.5N 39.9W 70 KT 80 MPH
48H 15/0600Z 36.9N 39.5W 65 KT 75 MPH
60H 15/1800Z 36.7N 39.4W 60 KT 70 MPH
72H 16/0600Z 36.5N 39.7W 55 KT 65 MPH
96H 17/0600Z 36.5N 42.5W 45 KT 50 MPH
120H 18/0600Z 38.0N 43.0W 40 KT 45 MPH

$$
Forecaster Reinhart
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I’m sorry, but Lee is an ugly looking hurricane. I’m not at all impressed with its presentation. It almost looks subtropical.
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From Senor 57

More like 75 kts in NE quadrant. Could make an argument that there may be higher winds not sampled, so maybe 80 kts now. Not even a Cat 2. 100kts was too high, even for last evening. I can't see NHC dropping 2 categories from one advisory to another, so I bet they go 85-90 kts. Surprise me, NHC.
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193
WTNT43 KNHC 131438
TCDAT3

Hurricane Lee Discussion Number 33
NWS National Hurricane Center Miami FL AL132023
1100 AM AST Wed Sep 13 2023

Lee continues to exhibit concentric eyewalls, but there are some dry
slots between those features. An SSMIS microwave image around 10Z
showed that both eyewalls were open, however, recent infrared
satellite images indicate that the inner eyewall appears to be
becoming better organized during the past few hours. The initial
wind speed is held at 100 kt, but this is near the high end of the
latest satellite intensity estimates. The Air Force Hurricane
Hunters are scheduled to investigate Lee this afternoon, and the
data they collect should provide a better assessment of the
hurricane's intensity and structure.

Satellite images suggest that Lee seems to be beginning its
northward turn on the western side of a subtropical ridge situated
over the central Atlantic. The latest initial motion estimate is
345/6 kt. Lee should gradually increase in forward speed while
moving northward on the west side of the ridge during the next
couple of days, taking the core of the system to the west of Bermuda
Thursday and Thursday night. The combination of a shortwave trough
and a building ridge extending into Atlantic Canada could cause Lee
to turn slightly to the left Friday night and Saturday, which will
likely bring Lee close to southeastern New England before it reaches
Maine and Atlantic Canada later in the weekend. Confidence is
increasing in the forecast track, and the model spread is mostly
along-track, associated with the system's forward speed/timing.
Overall, little change was made to the previous NHC track forecast,
and it remains very near the various consensus models.

Lee is expected to gradually weaken as it moves into an environment
of increasing vertical wind shear, slightly drier air, and over
progressively cooler waters during the next few days. However, the
large size of the system suggests that the weakening process should
be slow. In addition, Lee is expected to grow in size as it gains
latitude during the next few days. The NHC intensity forecast is
largely the same as the previous one and fairly close to the HCCA
and IVCN models. Regardless of the details, there is high
confidence that Lee will be a large hurricane near the coast of New
England Friday night and Saturday.

It should again be noted that the 34- and 50-kt wind speed
probabilities beyond 36 hours in the text and graphical products are
likely underestimating the risk of those winds occurring. This is
because the forecast wind field of Lee is considerably larger than
average compared to the wind field used to derive the wind speed
probability product.


KEY MESSAGES:

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,
Bermuda, the U.S East Coast, and Atlantic Canada into the weekend.

2. Tropical storm conditions, heavy rainfall, and high surf are
expected to impact Bermuda beginning early Thursday, and a Tropical
Storm Warning is in effect for the island.

3. There is an increasing risk of wind, coastal flooding, and rain
impacts from Lee in portions of New England and Atlantic Canada
beginning on Friday and continuing through the weekend. Watches
will likely required for portions of these areas later today or
tonight. Due to Lee's large size, hazards will extend well away
from the center, and there will be little to no significance on
exactly where the center reaches the coast.


FORECAST POSITIONS AND MAX WINDS

INIT 13/1500Z 26.4N 67.2W 100 KT 115 MPH
12H 14/0000Z 27.6N 67.7W 95 KT 110 MPH
24H 14/1200Z 29.6N 68.2W 90 KT 105 MPH
36H 15/0000Z 31.8N 68.2W 85 KT 100 MPH
48H 15/1200Z 34.6N 67.6W 80 KT 90 MPH
60H 16/0000Z 37.9N 67.1W 75 KT 85 MPH
72H 16/1200Z 41.1N 67.2W 70 KT 80 MPH
96H 17/1200Z 46.1N 66.6W 50 KT 60 MPH...POST-TROP/INLAND
120H 18/1200Z 52.1N 56.4W 35 KT 40 MPH...POST-TROP/INLAND

$$
Forecaster Cangialosi
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000
WTNT44 KNHC 131456
TCDAT4

Hurricane Margot Discussion Number 25
NWS National Hurricane Center Miami FL AL142023
Issued by the NWS Weather Prediction Center College Park MD
300 PM GMT Wed Sep 13 2023

Margot continues to exhibit a double eyewall structure based on
a recent SAR pass over the storm, with a well-defined inner core.
GOES-16 IR data shows the inner-eye feature occasionally obscured by
clouds, but overall the organization of Margot has changed little
over the last several hours. The latest microwave data in
conjunction with the SAR pass suggests the initial intensity may be
just a tad stronger compared to continuity, and so it will be set at
80 kt for this advisory.

Margot is slowing down as it moves within the flow between a
deep-layer ridge over the eastern Atlantic and a narrow upper trough
to its west. A general north to north-northwest motion should
continue over the next day or so before the track forecast becomes
very challenging. Margot is expected to become caught in weak
steering currents, with the global models showing a blocking ridge
developing to the north of the cyclone by late week into the
weekend. There are significant differences between the GFS and ECMWF
with regards to the strength and position of this ridge, which has
large implications in the longer-range track of Margot. The overall
consensus of the guidance suggests that Margot could make a
clockwise loop as the ridge builds, and the latest NHC forecast
shows little net motion between 36-72 hrs as the cyclone meanders
over the central Atlantic. At days 4-5, most models (except for the
ECMWF) show the ridge sliding eastward, allowing for Margot to
gain latitude, and the overall track forecast confidence remains
low.

The deep-layer shear is forecast to increase during the next 24 to
36 hrs, and this coupled with a likelihood of the upwelling of
cooler waters should result in a weakening trend. Drier air
surrounding the storm will also be a factor in causing a weakening
cyclone going into the weekend. The NHC intensity forecast is close
to the previous forecast and shows gradual decrease in strength
through 72 hrs, and in good agreement with the consensus of the
intensity aids. Although this forecast keeps Margot a tropical
cyclone through day 5, simulated satellite imagery from the global
models suggests these environmental factors could cause the system
to lose organized convection and become post-tropical early next
week as the storm lingers west of the Azores.


FORECAST POSITIONS AND MAX WINDS

INIT 13/1500Z 34.1N 40.4W 80 KT 90 MPH
12H 14/0000Z 35.0N 40.7W 75 KT 85 MPH
24H 14/1200Z 36.0N 40.2W 75 KT 85 MPH
36H 15/0000Z 36.8N 39.5W 70 KT 80 MPH
48H 15/1200Z 36.9N 39.4W 65 KT 75 MPH
60H 16/0000Z 36.5N 39.4W 60 KT 70 MPH
72H 16/1200Z 36.3N 40.2W 50 KT 60 MPH
96H 17/1200Z 36.0N 42.5W 45 KT 50 MPH
120H 18/1200Z 38.0N 42.5W 45 KT 50 MPH

$$
Forecaster Orrison/Blake
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From 57..

It appears that with the ingestion of last evening's G-IV dropsonde data into the models, they've come into better agreement on a track to western Nova Scotia Saturday evening. Still will see TS wind all along the NE U.S. coast Saturday, though.
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tireman4
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From the Eyewall..

Lee was determined to be post-tropical, which means it’s now essentially a gigantic nor’easter instead of a tropically-derived hurricane. It means absolutely nothing other than a classification change. Impacts are identical to forecast.

Lee is flinging very heavy rain onshore in Maine right now, with a band of torrential rain between Fredericton, NB and Acadia National Park.

Meanwhile, wind gusts have been ticking up around the region, with Grand Manan as high as 123 km/hr (77 mph), Halifax as high as 117 km/hr (73 mph), Mt. Washington, NH to 74 mph, St. John, NB to 85 km/hr (53 mph), Nantucket to 55 mph, and Eastport, ME to 62 mph.

The high tide cycle ongoing right now, as well as the next one this evening will be the highest for these areas. Yarmouth, NS is seeing about a 0.6m (2 ft) surge, Halifax 0.7m, and St. John about 0.5m. These are generally in line with expectations, maybe a smidge under. Surge of up to 1.5m (5 ft) is possible in Nova Scotia. With Lee’s center still technically south of Nova Scotia, the highest surge is yet to come. In addition, some potent waves will be coming ashore in Nova Scotia as well, with a buoy near Lee’s center at 8 AM AST reporting 30 foot waves.

So I think the takeaway here right now: Worst is over for southern New England, and it was handled pretty well as expected. Maine, particularly Downeast are in the height of the storm now, and it will wind down this afternoon. Nova Scotia, New Brunswick, and PEI will be in the height of the storm shortly if not already, and it will wind down tonight.
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No concern to us at all but southern Florida might need to watch out for a storm here within 10 days or so.
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