2023 Hurricane Season Discussion

[tireman4]

Hurricane Lee

[tireman4]

URNT12 KWBC 081208
VORTEX DATA MESSAGE AL132023
A. 08/11:41:56Z
B. 17.88 deg N 054.05 deg W
C. NA
D. 941 mb
E. 165 deg 11 kt
F. CLOSED
G. E04/14/9
H. 121 kt
I. 349 deg 5 nm 11:40:37Z
J. 080 deg 134 kt
K. 353 deg 7 nm 11:40:07Z
L. 97 kt
M. 173 deg 9 nm 11:44:32Z
N. 254 deg 113 kt
O. 173 deg 8 nm 11:44:12Z
P. 15 C / 2450 m
Q. 26 C / 2445 m
R. 19 C / NA
S. 12345 / NA
T. 0.01 / 1 nm
U. NOAA3 0313A LEE OB 15
MAX FL WIND 134 KT 353 / 7 NM 11:40:07Z

[tireman4]

Mr 57 concerning Lee

Once Lee reaches the latitude of Cape Cod, it will be in the process of becoming ET. It's wind field will double in size, with TS winds raking the coast of Maine down to as far west as eastern Long Island. Max winds may only be 50-60 kts by then and 50 kts at final landfall. Even though the pressure will be quite low, the expansion of the wind field will reduce the pressure gradient and max sustained winds will drop. TS wind may extend out to 250 miles west of its center as it passes Cape Cod.

[tireman4]

Margot...

Tropical Storm Margot Discussion Number 16
NWS National Hurricane Center Miami FL AL142023
900 AM GMT Mon Sep 11 2023

This morning's satellite presentation consists of an isolated area
of deep convection near Margot's surface center and a curved band
displaced about 160 mi to the northeast beneath upper-level
southerly diffluent flow. This distinctive cloud pattern is a
result of very dry mid-tropospheric air intruding from the
southwest and wrapping around and into the northeast sector of the
cyclone. The Dvorak satellite intensity estimates from TAFB and
SAB haven't changed since last night, and the initial intensity is
held at 55 kt for this advisory.

The latest GFS and ECMWF sounding analyses show modest northwesterly
shear undercutting the diffluent southerly flow aloft while drying
and stabilizing the mid-level portion of the atmosphere. In fact,
the statistical-dynamic SHIPS indicates 40 to 50% relative humidity
in the surrounding environment. The deterministic and SHIPS models
still indicate, however, that the upper-level trough providing these
inhibiting conditions will lift northeastward soon, allowing
anticyclonic upper-tropospheric flow to develop over Margot. As a
result, the cyclone should strengthen, and the NHC intensity
forecast follows suit and indicates the cyclone becoming a hurricane
in less than 24 hours while intensifying further through mid-week.
Weakening is predicted beyond day 3 as the thermodynamic environment
in the mid-latitudes of the central Atlantic becomes even less
favorable. The official intensity forecast follows the HFIP HCCA
corrected consensus intensity model through 48 hours, then is based
on a blend of the HCCA, Decay SHIPS, and the IVCN intensity aids.

Margot's initial motion during the past 12 hours has been north, or
360/7 kt. A mid-tropospheric subtropical ridge extending from west
Africa to the eastern subtropical Atlantic should steer the cyclone
in a generally northward trajectory through an amplified weakness
over the central Atlantic over the next 72 hours. Through the
remaining period, Margot is expected to slow in forward speed, and
possibly meander, in response to high pressure building to the
north of the cyclone over the central north Atlantic. The NHC
forecast track is adjusted slightly to the right beyond 48 hours,
and lies between the previous forecast and the TVCA simple average
multi-model consensus.


FORECAST POSITIONS AND MAX WINDS

INIT 11/0900Z 25.3N 40.0W 55 KT 65 MPH
12H 11/1800Z 26.6N 39.9W 60 KT 70 MPH
24H 12/0600Z 28.6N 39.8W 70 KT 80 MPH
36H 12/1800Z 30.8N 40.1W 75 KT 85 MPH
48H 13/0600Z 32.7N 40.8W 75 KT 85 MPH
60H 13/1800Z 34.0N 41.7W 75 KT 85 MPH
72H 14/0600Z 35.0N 42.0W 75 KT 85 MPH
96H 15/0600Z 36.7N 41.0W 70 KT 80 MPH
120H 16/0600Z 37.1N 40.9W 60 KT 70 MPH

$$
Forecaster Roberts

[tireman4]

This FL wind data screams eyewall replacement cycle due to the double wind maxima. At this rate, the window of intensification is closing for #Lee & y’all can say the chances of rapid intensification are on the very edge of the table if not falling off. #tropicswx https://t.co/zt52sPVcIl pic.twitter.com/QPLQmnU90g
-- Vorti𝕏 (@VortixWx) September 11, 2023

[tireman4]

#Lee’s eyewall is partially open to the south side, likely due to some shear still hanging around. With this kind of structure, if things don’t improve, it would be rather hard to rapidly intensify. The most recent VDM also tells the same story. Shear is still hanging on. #tropicswx

[snowman65]

I know anything can happen but.... how is the GOM looking for any potential patterns for the rest of September?

[Stratton20]

The pattern down the road spells good news for texas, I think we are very likely safe from anymore threats with the frequent troughing over the SE us, id say the eastern gulf has a more higher threat for getting hit, id say odds of texas getting hit are now less than 5%, so very unlikely anything comes this way

[Cpv17]

The pattern down the road spells good news for texas, I think we are very likely safe from anymore threats with the frequent troughing over the SE us, id say the eastern gulf has a more higher threat for getting hit, id say odds of texas getting hit are now less than 5%, so very unlikely anything comes this way

I’m done with this years hurricane season. I’m trying to find out more about next years season, which as of right now, appears to be much more active in the Gulf.

[tireman4]

ZCZC MIATCDAT3 ALL
TTAA00 KNHC DDHHMM

Hurricane Lee Discussion Number 25
NWS National Hurricane Center Miami FL AL132023
1100 AM AST Mon Sep 11 2023

Lee has been holding steady in strength this morning. The NOAA
Hurricane Hunters have been investigating Lee and found that the
minimum pressure was around 948 mb while a combination of the
measured flight-level and SFMR winds support holding the initial
intensity at 105 kt. The aircraft data have also shown a clear
indication of concentric eyewalls, which will likely cause
fluctuations, both up and down, in Lee's intensity over the next day
or two.

The major hurricane is moving slowly toward the northwest at about
7 kt. A continued slow motion between west-northwest and northwest
is expected during the next couple of days as Lee continues to be
steered by a mid-level high to its north-northeast. Around the
middle of the week, the ridge is expected to shift eastward as a
mid- to upper-level trough amplifies over the eastern U.S. This
pattern change should cause Lee to turn northward with an increase
in forward speed. The models have generally changed little this
cycle, and only small changes were made to the previous NHC track
forecast. Lee is likely to pass near, but to the west of Bermuda,
late Thursday and Friday and be situated offshore of the
mid-Atlantic states and New England by the end of the forecast
period.

As mentioned above, fluctuations in strength are likely in the
short term due to eyewall replacement cycles, but there is an
opportunity for some strengthening during that time since the
system is expected to remain over very warm waters and in
relatively low wind shear conditions. Beyond a couple of days,
however, progressively cooler waters and a notable increase in
shear should cause Lee to gradually weaken. Although the weakening
is forecast later in the week, Lee is expected to significantly
increase in size and hazards will extend well away from the center
of the storm by the end of the forecast period.


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. Lee could bring strong winds, rainfall, and high surf impacts to
Bermuda later this week. Interests there should monitor the latest
forecasts.

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


FORECAST POSITIONS AND MAX WINDS

INIT 11/1500Z 23.5N 63.5W 105 KT 120 MPH
12H 12/0000Z 23.9N 64.4W 110 KT 125 MPH
24H 12/1200Z 24.4N 65.5W 115 KT 130 MPH
36H 13/0000Z 24.9N 66.5W 110 KT 125 MPH
48H 13/1200Z 25.7N 67.2W 100 KT 115 MPH
60H 14/0000Z 27.0N 67.7W 95 KT 110 MPH
72H 14/1200Z 28.8N 68.0W 90 KT 105 MPH
96H 15/1200Z 33.1N 67.6W 80 KT 90 MPH
120H 16/1200Z 38.9N 67.1W 70 KT 80 MPH

$$
Forecaster Cangialosi

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