[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 280001
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
801 PM EDT Fri Sep 27 2019

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 1800 UTC surface analysis and satellite imagery through
2345 UTC.

...SPECIAL FEATURES...

Hurricane Lorenzo is centered near 20.3N 43.6W at 27/2100 UTC or
1370 nm SW of the Azores, moving NNW at 10 kt. Estimated minimum
central pressure is 948 mb. Maximum sustained wind speed is 110
kt with gusts to 135 kt. Numerous strong convection is from 18N-
21N between 41W-45W. Scattered moderate convection is elsewhere
from 14N-24N between 37W-50W. A turn toward the north is expected
on Saturday, followed by a turn toward the north-northeast on
Sunday. Lorenzo is a category 3 hurricane on the Saffir-Simpson
Hurricane Wind Scale. Gradual weakening is expected during the
next few days. However, Lorenzo is expected to remain a powerful
hurricane through the weekend. Please read the latest NHC
forecast/ advisory under AWIPS/WMO headers MIATCMAT3/WTNT23 KNHC
or www.hurricanes.gov for more details.

Karen degenerated into a surface trough at 27/2100 UTC and the
last advisory has been emitted by the National Hurricane Center.
The remnants of Karen are centered near 29.3N 58.5W or 370 nm
east- southeast of Bermuda, moving northeast at 5 kt. Estimated
minimum central pressure is 1007 mb. Maximum sustained wind speed
is 30 kt with gusts to 40 kt. Scattered moderate to isolated
strong convection is from 26N- 31N between 56W-61W. The remnants
of Karen are moving toward the northeast, but should stall and
then begin moving westward over the weekend. Winds associated with
the remnants are expected to gradually decrease during the next
several days. Please read the latest NHC forecast/advisory under
AWIPS/WMO headers MIATCMAT2/WTNT22 KNHC or www.hurricanes.gov for
more details.

...A heavy rain event in Central America and Southeastern
Mexico...

Southwesterly monsoonal flow is pushing abundant moisture from
the tropical Pacific Ocean toward Central America. Heavy rainfall
is expected in Central America, through the weekend. The greatest
threat for heavy rainfall will migrate northwestward to areas
from western Nicaragua, southern Honduras, southern Guatemala, to
southern Mexico, including in the Mexican states of Chiapas,
Oaxaca and Guerrero. It is possible that the heavy rains may lead
to flash floods and mudslides, especially in areas of mountainous
terrain and areas near the Pacific coast.

...TROPICAL WAVES...

A tropical wave is in the eastern Atlc from 0N to 12N with axis
near 30W, moving W at 10-15 kt. Scattered showers and tstms are
from 07N to 10N between 28W and 31W.

A tropical wave is from 08N to 19N with axis near 59W, moving W
at 10 kt. Isolated showers are from 13N to 19N between 57W and
61W.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through the coastal sections of Senegal near
12N17W to 07N21W to 06N27W. The ITCZ begins near 06N32W and
continues to 08N38W. Besides the convection mentioned in the
tropical waves section, scattered showers are from 01N to 09N
between 30W and 37W.

GULF OF MEXICO...

Multi-layered water vapor imagery show very dry air across the
basin, except for the SW gulf where the CIRA layered precipitable
water imagery show abundant shallow moisture being advected from
the EPAC monsoon. This moisture along with middle level divergent
flow support scattered showers and tstms S of 22N over the Bay of
Campeche. Gentle to moderate east to southeast winds dominate the
basin due to a weak pressure gradient across the region.

A trough will form over the western Gulf and move slowly westward,
reaching the northeast coast of Mexico on Sat. High pressure will
prevail elsewhere across the region with moderate to fresh return
flow.

CARIBBEAN SEA...

A heavy rainfall event is expected in Central America and
southeastern Mexico this weekend. Please read the Special
Features section above for more details.

A middle level low over the Bahamas extends a trough across Cuba
and the NW Caribbean. This is supporting a surface trough from the
Great Bahama Bank through central Cuba to 19N80W, along with
scattered heavy showers and tstms N of 18N between 75W and 82W.
Similar shower activity is within 90 nm of the northern coast of
Colombia and over central Hispaniola. Otherwise, gentle to
moderate trades are across the basin due to a weak pressure
gradient across the region.

Trade winds will increase over much of the central and western
Caribbean through early next week . Swells generated from Lorenzo
will continue to propagate into the tropical N Atlc and eastern
Caribbean passages this weekend into early next week.

ATLANTIC OCEAN...

Refer to the sections above for details on the tropical waves,
Hurricane Lorenzo and and the remnants of Karen.

A middle level low over the Bahamas extends a trough across Cuba
and the NW Caribbean. This is supporting a surface trough from the
Great Bahama Bank through central Cuba, along with scattered heavy
showers and tstms S of 25N between 73W and 79W. Divergent flow
between the middle level low and a middle level high centered just
N of Puerto Rico is supporting scattered showers and tstms from
19N to 26N between 57W and 69W. The remainder eastern Atlc N of
20N and east of Hurricane Lorenzo is under the influence of the
Azores high.

A surface trough, remnants of former Tropical Storm
Karen, will drift westward into the forecast waters late this
weekend into early next week. High pressure will build N of the
area. The pressure gradient between these features will increase
winds and seas across the northern waters this weekend into early
next week.

$$
Ramos
This weather bulletin was brought to you by:
www.nashvilleweather.net