[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 081022
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1205 UTC Thu Oct 8 2020

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 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 0600 UTC surface analysis and satellite imagery through
1000 UTC.

...SPECIAL FEATURES...

Hurricane Delta is centered near 23.4N 91.8W at 08/0900 UTC or
390 nm SSE of Cameron Louisiana moving NW at 13 kt. Estimated
minimum central pressure is 973 mb. Maximum sustained wind speed
is 85 kt with gusts to 105 kt. Numerous strong convection is
active within 90 nm of the northeastern semicircle and 120 nm of
the southeastern semicircle. On the forecast track, the
center of Delta will move over the southern and central Gulf of
Mexico through today, and approach the northern Gulf coast on
Friday. Delta is forecast to move inland by late Fri or Fri
night. Strengthening is forecast while the hurricane moves over
the southern and central Gulf of Mexico through today, and Delta
is expected to become a major hurricane again. Some weakening is
forecast as Delta approaches the northern Gulf coast on Fri. Peak
seas near the center of Delta are forecast to build to at least
33 feet today as Delta moves over the central Gulf, with an
expanding area of swell supporting combined seas in excess of 8 ft
over most of the central and western Gulf. Very heavy rainfall,
hurricane force winds, and a life- threatening storm surge are
expected along portions of the northern Gulf Coast Fri into early
Sat. The heavy rain will then spread inland across the Mississippi
Valley. Please read the latest NHC Public Advisory at
https://www.nhc.noaa.gov/text/MIATCPAT1.shtml and Forecast/
Advisory at https://www.nhc.noaa.gov/text/MIATCMAT1.shtml for more
details.

...TROPICAL WAVES...

A tropical wave axis is along 23W/24W from 03N-16N, moving W at
15-20 kt. Scattered moderate convection is noted from 10N-13N
between 21W-24W.

A tropical wave axis is along 59W from 06N-22N, moving W at 10
kt. No significant convection is noted.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from the coast of Africa near 10N15W
to 07N30W. The ITCZ continues from 07N30W to 07N55W. Numerous
moderate to isolated strong convection is ongoing off African
coast from Liberia to Senegal. Scattered moderate convection is
noted from 05N-08N between 30W-38W.

GULF OF MEXICO...

The central and western Gulf of Mexico is currently dominated by
the circulation of Hurricane Delta. See Special Features section
above for details on Delta.

Elsewhere across the Gulf of Mexico outside of the main area of
Delta, a scatterometer satellite pass indicated fresh NW to N
winds funneling along the coast of Mexico from Tampico to
Veracruz. Seas are estimated to be 8 to 9 ft in the far southwest
Gulf, mainly due to swell. Buoy and platform data shows fresh to
strong NE winds and 6 to 8 ft seas over the northwest and north-
central Gulf ahead of the advancing Delta. Buoy and ship
observations show strong SE to S winds and 8 to 10 ft seas are
observed over the east-central Gulf, just east of Delta. Moderate
to fresh SE winds and 3 to 5 ft seas are observed in the far
eastern Gulf of Mexico close to the Florida coast.

Hurricane Delta near 23.4N 91.8W 973 mb at 5 AM EDT
moving NW at 13 kt. Maximum sustained winds 85 kt gusts 105 kt.
Delta will move to 24.6N 93.0W this afternoon, 26.4N 93.7W Fri
morning, 28.8N 93.4W Fri afternoon, move inland and weaken to a
tropical storm near 31.3N 92.4W Sat morning, move inland and
weaken to a tropical depression near 33.3N 90.9W Sat afternoon,
and become a remnant low and move to 34.6N 89.0W Sun morning.
Delta will dissipate early Mon. Winds and seas will diminish
starting Fri and Sat through early next week.

CARIBBEAN SEA...

An upper-level low is centered near Jamaica. Upper level
divergence on the southeast side of the upper low is supporting
clusters of showers and thunderstorms from the coast of Colombia
to off the coasts of Haiti and eastern Cuba. Scattered showers and
thunderstorms are also active from Providencia Island to Jamaica.
Dry, subsident NE flow aloft between the upper low and an upper
anticyclone over the eastern Gulf of Mexico is suppressing most
convective activity over the remainder of Cuba and the northwest
Caribbean. High pressure centered northeast of the Bahamas is
supporting moderate trade winds across the eastern Caribbean,
although fresh trade winds are possible off Venezuela and across
the ABC islands. These fresh winds will be short lived as the high
pressure should weaken this morning. Fresh southerly are likely
ongoing over the Yucatan Channel, although should be diminishing
through the morning as Delta moves farther away. Light to gentle
breezes and slight seas are noted elsewhere.

For the forecast, building high pressure over the northwest
Atlantic will support fresh trade winds and moderate seas over the
south-central Caribbean, and gentle to moderate trade winds and
slight seas elsewhere Fri. Winds and seas will diminish across the
basin through early next week as the high pressure shifts east.

ATLANTIC OCEAN...

West of 65W, 1018 mb high pressure is centered northeast of the
Bahamas, near 28N71W. This is supporting moderate SE winds over
the Old Bahama Channel, and light breezes and slight seas
elsewhere west of 65W. No significant shower or thunderstorm
activity is observed. For the forecast, high pressure centered
northeast of the Bahamas will dissipate this morning ahead of a
cold front approaching the area from north. The front will stall
along roughly 27N Fri, then lift north as a warm front through
Sat. A weak pressure pattern will follow and gentle to moderate
winds and slight to moderate seas will persist Sun and Mon.

Farther east, a relatively weak 1019 mb high pressure area is
centered 30N42W, displaced southward due a frontal boundary over
the north-central Atlantic. Farther east, several weak surface
troughs are noted north of 20N between 30W-40W. This pattern is
resulting in a somewhat subdued pressure gradient, supporting
gentle to moderate trade winds farther south into the tropical
Atlantic. Fresh NE winds were noted earlier off the coast of
Africa. Seas are 4 to 6 ft.

$$

Christensen
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