Atlantic Tropical Discussion

Active Tropical Systems Basin Outlooks Satellite
Atlantic Basin Tropical Discussion
 
800 
AXNT20 KNHC 240017 AAA
TWDAT 

Tropical Weather Discussion...update to Karl
NWS National Hurricane Center Miami FL 
805 PM EDT FRI SEP 23 2016

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
2315 UTC.

...SPECIAL FEATURES...

Tropical Storm Karl is centered near 30.3N 65.2W at 24/0000 UTC
or about 125 nm south-southwest of Bermuda moving north at 11 kt.
Estimated minimum central pressure is 990 mb. Maximum sustained
wind speed is 55 kt with gusts to 65 kt. NOAA Hurricane Hunter
aircraft reports that Karl is clightly stronger. Scattered to
numerous strong convection is within 45 nm of a line from 30N65W
to 32N66W with scattered moderate to isolated strong convection
covering the remainder of the area from 28N-33N between 64W-68W.
Please see the latest NHC Public Intermediate Advisory under
AWIPS/WMO headers MIATCPAT2/WTNT32 KNHC AND NHC Forecast/
Advisory under AWIPS/WMO headers MIATCMAT2/WTNT22 KNHC for more
details.

Tropical Storm Lisa was downgraded to Tropical Depression at
23/2100 UTC. Tropical Depression Lisa is centered near 22.5N
36.5W at 23/2100 UTC or about 810 nm west-northwest of the Capo
Verde Islands and about 1050 nm south-southwest of the Azores
moving northwest at 6 kt. Estimated minimum central pressure is
1009 mb. Maximum sustained wind speed is 30 kt with gusts to 40
kt. Lisa is void of any deep convection. Please see the latest
NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT3/ WTNT23
KNHC for more details.

...TROPICAL WAVES... 

Tropical wave in the east Tropical Atlantic extends along
19W/20W from 6N-15N moving west near 10 kt over the past 12
hours. Wave coincides with a broad 700 mb global models trough
and is embedded within a broad surge of moisture as seen on the
Total Perceptible Water imagery. No associated deep convection
is noted. 

Tropical wave in the west Tropical Atlantic extends along 50W/
51W from 10N-18N moving west near 15 kt over the past 12 hours.
Wave coincides with a broad 700 mb global models trough and is
embedded within an isolated surge of moisture as seen on the
Total Perceptible Water imagery. No associated deep convection
is noted. 

Tropical wave in the south Gulf of Mexico extends along 93W
south of 20N across south Mexico into the east Pacific region
moving west near 15 kt over the past 24 hours. Wave is within a
weak 700 mb global model trough and is embedded within an area
of moisture as seen on the Total Perceptible Water imagery. No
associated deep convection is noted. 

...ITCZ/MONSOON TROUGH... 

The Monsoon Trough extends across Africa into the east Tropical
Atlantic near 19N16W then along 14N20W 7N22W to 8N34W. Scattered
moderate to isolated strong convection is within 90 nm north
of the monsoon trough between 26W-30W. 

...DISCUSSION...

GULF OF MEXICO...

An upper ridge anchored over east Texas covers the northwest
Gulf of Mexico while an upper trough extending south from an
upper low over south Georgia covers the northeast Gulf. Westerly
zonal flow aloft covers the south Gulf south of 24N. The upper
ridge and trough are creating a diffluent environment over the
west Gulf to generate scattered to numerous showers and isolated
thunderstorms from 24N-28N between 90W-97W. A weakening surface
trough extends from the west Atlantic across south Florida and
Florida Keys to 24N85W with scattered to numerous showers and
scattered thunderstorms inland and along the immediate coast of
Florida south of a line from Melbourne to Tampa. Isolated
showers and possible isolated thunderstorms dot the north Gulf
north of 26N west of 88W to inland over Texas. A surface ridge
has built south over the Gulf anchored by a 1024 mb high over
eastern Kentucky and a weak 1018 mb high along the Mississippi
coast. Weak high pressure will prevail through this weekend. An
early season cold front will approach the northwest Gulf early
next week.  

CARIBBEAN SEA...

An upper low is centered along the south coast of Hispaniola
near 18N73W extending an upper trough axis east to the Leeward
Islands. The remainder of the Caribbean is dominated by westerly
flow aloft. Easterly surface flow combined with westerly flow
aloft is generating scattered showers and isolated thunderstorms
from 11N-16N between 77W-85W including portions of Central
America. Afternoon showers and thunderstorms have developed
inland over Hispaniola, Jamaica, and Cuba. The easterly winds
over the Lesser Antilles is generating isolated showers and
possible isolated thunderstorms north of 12N between 61W-68W.
Easterly trade winds will increase over the central Caribbean
this weekend as high pressure builds over the west Atlantic and
Tropical Storm Karl moves north of the discussion area. 

...HISPANIOLA...

Currently scattered showers and isolated thunderstorms prevail
across the island this evening. The upper low will continue to
provide moisture and coupled with the easterly trade winds will
bring afternoon/evening showers and thunderstorms through the
weekend.

ATLANTIC OCEAN... 

The upper trough over the east Gulf of Mexico is supporting a
surface trough that extends from 31N79W along 26N80W then across
extreme south Florida and along the Florida Keys with scattered
showers and isolated thunderstorms within 45 nm either side of
the surface trough. The upper low over the Caribbean extends an
upper trough axis north over the west Atlantic to 29N75W and is
generating isolated showers and thunderstorms from 21N-27N
between 71W-78W. Scattered showers and isolated thunderstorms
continue to trail Tropical Storm Karl within 90/120 nm of a line
from 22N62W to 32N61W. The remainder of the Atlantic north of
Karl and Lisa is dominated by a surface ridge, anchored by a
pair of 1025 mb highs near 32N26W and 33N44W. Tropical Storm
Karl is expected to briefly becoming a hurricane Saturday night
as it accelerates northeastward. Tropical Depression Lisa is
expected to continue along a northwestward track becoming a post-
tropical/remnant low Saturday afternoon.  

For additional information please visit
http://www.hurricanes.gov/marine

$$
PAW