[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 091719
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Fri Jul 9 2021

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
1730 UTC.

...SPECIAL FEATURES...

Tropical Storm Elsa is over eastern Long Island near 41.0N,
72.1W. Elsa is moving toward the northeast near 27 kt, and this
general motion is expected to continue with an increase in forward
speed during the next couple of days. Maximum sustained wind speed
is 45 kt with gusts to 55 kt. On the forecast track, the center
of Elsa will move near eastern Long Island and the coast of
southern New England through this afternoon, and then offshore the
northeastern United States coast by this evening. The system
should move over Atlantic Canada by late tonight and Saturday. As
Elsa moves near southern and coastal New England today, heavy
rainfall could lead to considerable flash and urban flooding.
Isolated minor river flooding is also expected.

Please read the latest NHC Public Advisory at
https://www.nhc.noaa.gov/text/MIATCPAT5.shtml, Forecast/Advisory
at https://www.nhc.noaa.gov/text/MIATCMAT5.shtml, and the High
Seas Forecast issued by the NWS Ocean Prediction Center at
https://ocean.weather.gov/shtml/NFDHSFAT1.php for more details.
For marine information within 60 nm of the coast, please see
products from your local NWS Weather Forecast Office at
www.weather.gov.

...TROPICAL WAVES...

A tropical wave is near 29W south of 10N, moving west at 10 to 15
kt. An area of moderate scattered convection within 120 nm east of
the wave, south of 5N.

A central Atlantic tropical wave with a large amplitude has its
axis near 44W south of 24N, moving quickly west at 15 to 20 kt.
No convection is noted at this time.

A tropical wave near 68W south of 12N in the eastern Caribbean,
extends over western Venezuela and eastern Colombia, moving west
at 15 to 20 kt. Isolated moderate convection is noted within 60 nm
of the coast of Venezuela.

A tropical wave is in the far southwest Caribbean along 83W,
south of 13N, moving west at 10 to 15 kt. Scattered moderate to
isolated strong convection is noted within 60 nm of the coast of
Panama and Costa Rica, due in part to the tropical wave.

...MONSOON TROUGH/ITCZ...

The monsoon trough axis extends from the coast of Guinea-Bissau
near 11N15W southwest to 07N25W. The ITCZ extends from 06N31W to
07N43W. Scattered moderate convection is noted south of the
monsoon trough to 07N between the coast of Sierra Leone and 18W.

GULF OF MEXICO...

A surface ridge extends from western Atlantic across central
Florida to the northeast Gulf. A 1400 UTC scatterometer pass
indicated fresh to strong SE winds in the Gulf west of 90W. The
same scatterometer pass indicated fresh SE winds off the Texas
coast, between the surface ridge and 1010 mb low pressure over
South Texas. Gentle to moderate winds are noted elsewhere, except
light breezes are noted along the coast of Florida. Scattered
showers and a few thunderstorms are evident off central Texas
coast to off northeast Mexico. Seas are 6 to 8 ft over the
western Gulf, 4 to 6 ft seas in the southwestern Gulf and 3 to 5
ft over the eastern Gulf.

For the forecast, fresh SE winds will persist over the northwest
Gulf between the high pressure and lower pressure over Texas
through at least late Sat. Similarly, a trough will form off
northwest Yucatan Peninsula each evening, supporting fresh or
even strong winds during overnight hours through late Tue.
Meanwhile, gentle to moderate winds and slight seas will persist
over the eastern Gulf.

CARIBBEAN SEA...

A scatterometer pass from this morning revealed strong trades in
the south-central Caribbean. Winds may be near gale-force off the
coast of Colombia. Seas are estimated to be as high as 16 ft in
the area of near gale-force winds. Seas in excess of 8 ft are also
evident as far east as 65W, due to the long duration and fetch of
fresh to strong trade winds across the eastern Caribbean.
Moderate E winds and 3 to 5 ft seas are noted over the northwest
Caribbean, except for within the Gulf of Honduras where winds are
fresh with seas 4 to 6 ft. There are scattered showers and
thunderstorms off Panama and Costa Rica due to trade winds
convergence, local drainage flow and perhaps aided by a tropical
wave moving through that area. No significant shower or
thunderstorms activity is noted elsewhere.

For the forecast, the subtropical ridge north of the area
combined with the Colombian low will enhance strong to near gale-force
winds north of Colombia through midday with strong winds
continuing into the weekend. Strong trades will also prevail in
the Gulf of Honduras into Sat, then pulse nightly into the middle
of next week.

Of note, an atmospheric Kelvin wave along with successive bursts
in the easterly trades will influence the formation of a low along
the monsoon trough over Panama and Costa Rica, resulting in an
enhanced risk of heavy rainfall for these countries and adjacent
Caribbean waters through this weekend.

ATLANTIC OCEAN...

West of 65W, a surface ridge extends from near Bermuda to central
Florida. Recent scatterometer satellite data and buoy
observations show moderate to fresh E winds south of the ridge
axis through the southern Bahamas. Light to gentle breezes
persist along the ridge axis, through the northern Bahamas. The
scatterometer data also shows moderate SSW winds north of 29N
between 72W and 79W. Scattered moderate convection is also noted
in this area of winds. Seas are 3 to 5 ft north of 25N and 4 to 6
ft farther south.

For the forecast, the surface ridge extending from Bermuda to
central Florida will lift north of the area by early next week.
This will support moderate to fresh E winds south of the ridge
axis, with winds pulsing to fresh to strong along the north coast
of Hispaniola mainly during the evening hours, reaching westward
into the Windward Passage.

Elsewhere farther east, 1033 mb high pressure is centered west of
the Azores near 36N38W. West of 35W, this supporting gentle to
moderate NE to E winds and 4 to 6 ft seas north of 25N, and
moderate to fresh trades south of 25N with 5 to 7 ft seas. East of
35W, fresh to strong NE winds and 7 to 9 ft seas are noted north
of 15N, and gentle to moderate flow and 5 to 7 ft are noted south
of 15N.

$$
DELGADO/MORA
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