[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 292325
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Wed Aug 30 2023

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 1800 UTC surface analysis and satellite imagery through
2300 UTC.

Hurricane Idalia is centered near 26.1N 84.8W at 29/2100 UTC or
170 nm SW of Tampa, FL, moving N at 14 kt. Estimated minimum
central pressure is 972 mb. Maximum sustained wind speed is 85 kt
with gusts to 105 kt. Peak seas are near 28 ft. Seas of 12 ft or
greater are found within 90 nm W semicircle, 150 nm NE quadrant
and 120 nm SE quadrant. A buoy near 25.7N 83.7W recently reported
significant wave heights of 20 ft. Numerous strong convection is
seen within 75 nm of the center except 60 nm NW quadrant.
Scattered moderate isolated strong convection is elsewhere within
450 nm of the center. A northward to north-northeastward motion
is expected through tonight, with Idalia's center forecast to
reach the Big Bend coast of Florida on Wed morning. After
landfall, the center of Idalia is forecast to turn toward the
northeast and east, moving near or along the coasts of Georgia,
South Carolina, and North Carolina late Wed and Thu. Additional
strengthening is forecast, and Idalia is expected to become a
major hurricane tonight before it reaches the Big Bend coast of
Florida. Idalia is likely to still be a hurricane while moving
across southern Georgia, and possibly when it reaches the coast of
Georgia or southern South Carolina on Wed. A dangerous and life-
threatening storm surge is expected for portions of Florida's Gulf
Coast. Areas of flash and urban flooding, some of which may be
locally significant, are expected across portions of the west
coast of Florida, the Florida Panhandle, and southern Georgia
tonight into Wed.

Major Hurricane Franklin is centered near 31.4N 69.9W at 29/2100
UTC or 265 nm W of Bermuda, moving NE at 10 kt. Estimated minimum
central pressure is 947 mb. Maximum sustained wind speed is 110
kt with gusts to 135 kt. Peak seas are currently up to 40 ft. Seas
of 12 ft or greater extend outward to 180 nm SE quadrant and 120
nm SW quadrant. A NOAA buoy located near 31.8N 69.6W recently
reported winds of 71 kt gusting to 87 kt and seas of 34 ft.
Numerous moderate to isolated strong convection is noted north of
28.5N between 66.5W and 71.5W. A faster NE motion is expected
during the next few days. Winds of tropical storm force should
move north of 31N by 30/0600 tonight. Winds over 25 kt and seas
over 12 ft should move N of 31N by early afternoon Wed. Life-
threatening surf and rip currents generated by Franklin are
already affecting Bermuda and the east coast of the United States.
These conditions are expected to continue during the next several
days.

Tropical Depression Eleven is centered near 28.2N 51.8W at
29/2100 UTC or 715 nm ESE of Bermuda, moving NNW at 2 kt.
Estimated minimum central pressure is 1014 mb. Maximum sustained
wind speed is 30 kt with gusts to 40 kt. Peak seas are 10 ft
within the area of strongest winds. Scattered moderate isolated
strong convection prevails within 210 nm E semicircle. A
gradual turn toward the north and north-northeast at a slightly
faster forward speed is expected on Wed and Thu. Some slight
strengthening is possible during the next day or so, and the
depression could become a tropical storm on Wed.

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
Franklin, Idalia, and T.D. Eleven NHC Forecasts/Advisories and
Public Advisories at www.hurricanes.gov for more details.

...TROPICAL WAVES...

A tropical wave axis is located along 21W, moving W at 10-15 kt.
Scattered moderate isolated strong convection is within 120 nm of
the wave axis from 12N-17N. Environmental conditions appear
marginally conducive for gradual development of this system, and a
tropical depression could form later this week while the system
moves west-northwestward to northwestward across the eastern
tropical Atlantic. This system has a low chance of tropical
cyclone development within 48 hours and a medium chance within 7
days.

A tropical wave axis is in the Atlantic along 48W, from 17N
southward, moving W at around 15-20 kt. No significant convection
is evident with this tropical wave.

An eastern Caribbean tropical wave axis is along 63W from 17N
southward, moving W around 10-15 kt. Scattered moderate
convection is evident south of 16N between 56W and 66W.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through coastal Africa near 18N16W to
13N35W. All nearby convection is described in the Tropical Waves
section above.

...GULF OF MEXICO...

Please read the SPECIAL FEATURES section for details about
Hurricane Idalia, which is currently located in the eastern Gulf
of Mexico.

West of 90W, gentle to moderate winds and seas of 2-5 ft prevail.
Isolated moderate convection is over the west-central Gulf.

For the forecast, Hurricane Idalia will move to 28.3N 84.5W Wed
morning, move inland to near 31.0N 82.9W Wed afternoon, weaken to
a tropical storm near 32.9N 80.2W Thu morning, then will be north
of area near 33.9N 77.1W Thu afternoon. Idalia is expected to
become a major hurricane tonight. High pressure and improving
conditions will arrive in the wake of Idalia by Fri.

...CARIBBEAN SEA...

Refer to the Tropical Waves section above for details on a
tropical wave affecting the Lesser Antilles.

Hurricane Idalia is moving northward over the eastern Gulf of
Mexico, so conditions in the NW Caribbean are improving. To the
south of western Cuba and in the Yucatan Channel, S winds 20-25 kt
and seas 7-8 ft still prevail. Scattered moderate to isolated
strong convection is present north of 18N between 78W and 86W.
Fresh trades and 4-7 ft seas prevail over much of the eastern and
central basin. Light to gentle winds and 1-2 ft seas are in the
far SW Caribbean.

For the forecast, conditions will continue to improve over the NW
Caribbean this evening and tonight. Elsewhere, expect increasing
trades and building seas over the south-central Caribbean the
remainder of the week.

...ATLANTIC OCEAN...

Please read the SPECIAL FEATURES section for details about Major
Hurricane Franklin, T.D. Eleven, and on Hurricane Idalia in the
eastern Gulf of Mexico forecast to impact the waters off the SE
United States.

Scattered moderate convection is evident from 22N to 29N between
56W and 64W due to the influence of a mid to upper level feature.

Away from the influences of Franklin, Idalia and TD Eleven,
gentle to moderate winds dominate west of 35W with 4-5 ft seas.
East of 35W, fresh NE winds and 6-9 ft seas prevail from the Cabo
Verde Islands extending NE through the Canary Islands and continue
northeastward from there.

For the forecast, tropical storm conditions associated with
Franklin will continue to impact the waters north of 27N tonight
and tomorrow morning. Hurricane Idalia will move inland to 31.0N
82.9W Wed afternoon, weaken to a tropical storm near 32.9N 80.2W
Thu morning, 33.9N 77.1W Thu afternoon, 33.8N 74.2W Fri morning,
and 33.3N 71.8W Fri afternoon. Idalia will change little in
intensity as it moves to near 32.3N 69.6W Sat afternoon. Expect
increasing winds and building seas E of Florida beginning late
tonight as Idalia moves across the eastern Gulf of Mexico, and
eventually into the W Atlantic.

$$
Hagen
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