[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 271759
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Tue Sep 27 2022

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 31N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 1200 UTC surface analysis and satellite imagery through
1530 UTC.

...SPECIAL FEATURES...

Major Hurricane Ian is centered over the southeastern Gulf of
Mexico near 23.5N 83.3W at 27/1800 UTC, or 75 nm SSW of the Dry
Tortugas, FL, moving N at 9 kt. Minimum central pressure is 955
mb. Maximum sustained wind speed is 105 kt with gusts to 125 kt.
San Juan y Martinez, Cuba recorded a peak wind gust of 112 kt when
Ian passed over Cuba earlier this morning. The same station
measured 7.95 inches of rain during the 24 hr period ending at
27/1200 UTC. The city of Pinar del Rio experienced the calm eye of
Hurricane Ian. The calm lasted for 1 hr 30 min. Tropical storm
force winds extend outward 120 nm from the center. Seas of 12 ft
or greater are occurring over the far NW Caribbean, western
Straits of Florida and southeastern Gulf of Mexico, in the area
from 20.5N to 25N between 81W and 86W. Peak seas are reaching 25
ft. Numerous strong convection is seen within 75 nm of the center
in the S semicircle and 60 nm N semicircle. Numerous moderate and
scattered strong convection is noted elsewhere within 360 nm NE
quadrant, 210 nm SE quadrant, and 90 nm W semicircle. Scattered
moderate and isolated strong convection is found elsewhere within
510 nm NE quadrant, 300 nm SE quadrant and 210 nm W semicircle. On
the forecast track, the center of Ian is expected to pass west of
the Florida Keys later today and approach the west coast of
Florida within the hurricane warning area on Wed and Wed night.
Strengthening is expected later today through Wed. Ian is forecast
to approach the west coast of Florida as an extremely dangerous
major hurricane. Please read the latest High Seas Forecast issued
by the National Hurricane Center at website
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest NHC
Forecast/Advisory and Public Advisory at www.hurricanes.gov for
more details.

A 1008 mb low pressure located near 14N35W is producing scattered
moderate and isolated strong convection mainly in its NE quadrant
from 13.5N to 16N between 32W-35W. The disturbance has a medium
chance of developing into a tropical depression within the next
48 hours. The disturbance is forecast to meander for the next day
or so and then turn north-northwestward by early Thu. Please read
the latest NHC Tropical Weather Outlook at www.hurricanes.gov for
more details.

...TROPICAL WAVES...

An Atlantic Ocean tropical wave axis is along 21W from 06N-20N,
moving W at 10 kt. Scattered moderate isolated strong convection
is near the wave axis from 12N to 16.5N.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through the SW corner of Mauritania near
17N16W to 08N24W and 09N30W. The monsoon trough resumes from
13N37W to 10N45W. The ITCZ stretches from 10N45W to 10N50W to
12N58W. Aside from the convection mentioned in the sections above,
scattered moderate convection is noted S of the monsoon through
from 02.5N to 08N between 16W and 34W. Similar convection is seen
from 08N-15N between 57.5W-61W.

GULF OF MEXICO...

Major Hurricane Ian has emerged north of western Cuba. Please see
the Special Features section above for details on Hurricane Ian.
Strong winds and seas exceeding 8 ft associated with Ian are
located south of 27N and east of 89W. A cold front extends from
Cedar Key, FL near 29N83W to just north of Brownsville, TX near
26N98W. Fresh to strong N to NE winds are occurring N of the
front with 5-6 ft seas. Mainly moderate N winds prevail over the
southwestern Gulf, where seas are 3-5 ft, except for offshore
Veracruz, where fresh NW winds and 4-6 ft seas prevail. Scattered
moderate convection is noted over the western Gulf from 19N-27N
between 93W-98W.

Major Hurricane Ian moved off the northwest Cuba coast a few hours
ago and into the southeast Gulf. Ian will move to 24.4N 83.4W
this evening, 26.0N 83.0W Wed morning, 27.1N 82.5W Wed evening,
then move inland over west-central Florida to near 27.8N 82.1W Thu
morning. Winds and seas will gradually diminish across the basin
Fri and Sat as Ian continues to move northeast of the Gulf.

CARIBBEAN SEA...

As of 27/1500 UTC, convection, winds over 20 kt, and seas over 8
ft associated with Hurricane Ian are occurring over the NW
Caribbean Sea, mainly north of 19N and west of 76W. See the
Special Features section above for more details on Hurricane Ian.

Elsewhere, an upper-level trough extends over the eastern
Caribbean from Puerto Rico to NW Venezuela. The upper-trough is
inducing scattered moderate and isolated strong convection to its
east, from 12N-18N between 61W-72W, including over St. Lucia and
Martinique. In the SW Caribbean, the east Pacific monsoon trough
is inducing scattered moderate isolated strong convection mainly
south of 13.5N and west of 75.5W, including coastal areas near the
border of Panama and Costa Rica. Outside of Ian's circulation,
moderate trade winds prevail over the eastern and central
Caribbean. Gentle winds are across the SW Caribbean. Seas of 3-5
ft prevail east of 77W.

Major Hurricane Ian moved off the northwest Cuba coast a few hours
ago and into the southeast Gulf of Mexico. Tropical storm force
winds over the far northwest Caribbean off Cuba will diminish by
mid- afternoon as Ian continues to move north of the area, but
rough seas will persist into the overnight hours. Rough seas will
also continue in the Yucatan Channel through late Fri due to
northerly swell from Ian. Elsewhere gentle to moderate winds and
slight to moderate seas will persist across the basin.

ATLANTIC OCEAN...

Scattered moderate to strong convection associated with the outer
bands of Hurricane Ian are affecting waters to the west of 74W.
The strongest of this convection extends from the northwest
Bahamas to the Straits of Florida, including over South Florida.
Winds over 25 kt associated with Ian are currently confined to
the Straits of Florida, to the west of 79W. For more details on
Major Hurricane Ian, please see the Special Features section
above.

Elsewhere, an upper-level low located near 24N58W is inducing a
few thunderstorms near it. Moderate E winds and seas of 4-7 ft
prevail over the Atlantic from 15N-31N between 35W-70W. Farther
east, a 1013 mb low pressure near 24N25W is the remnant of
Tropical Storm Hermine. A surface trough running NE-SW goes
through the low from 27N23W to 21N28W. Scattered moderate
convection is noted from 24N-30N between 20W-28W. A recent ASCAT
pass shows strong NE to E winds on the north side of this low from
25N-31N between 20W-29W. A 27/1000 UTC altimeter pass measured
seas of 10 to 11 ft in this area.

For the forecast west of 55W, Major Hurricane Ian moved off the
northwest Cuba coast a few hours ago and into the southeast Gulf.
Ian will move to near 26N83W Wed morning, 27.1N 82.5W Wed
evening, then move inland over west-central Florida to near 27.8N
82.1W Thu morning. Expect deteriorating marine conditions off
northeast Florida starting Wed, with tropical storm or hurricane
conditions possible through Fri night. Elsewhere moderate to fresh
E to SE winds will persist.

$$
Hagen
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