AXNT20 KNHC 142348
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
747 PM EDT Wed Aug 14 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
A large surge of moisture will continue across Panama, Costa
Rica, and southern Nicaragua through the next 24-36 hours.
Environmental conditions remain highly favorable for heavy rains
to continue to accumulate, with higher localized totals near
strong topographical forcing. Costa Rica has received nearly 7
inches of rainfall in the last 24 hours, with 2-4″ of additional
rain in the last 6 hours mostly on the north Caribbean side of the
country. By Friday, the focus of heavy rainfall will shift north
to Nicaragua, El Salvador, southern Honduras/Guatemala and
southern Chiapas Mexico. Flash flooding and mudslides will be the
biggest hazard during this event.
A central Atlantic tropical wave with axis along 41W from 03N-12N,
is moving west at 10-15 kt. This wave is well depicted in model
guidance. Scattered showers are noted along the wave axis from
An eastern Caribbean tropical wave with axis along 65W from 09N-
20N, is moving west at 15-20 kt. Dry Saharan air prevails in the
wave’s environment inhibiting significant convection at this time.
A western Caribbean tropical wave with axis along 85W and S of
22N, is moving west at 10 kt. This feature is enhancing
convection along the monsoon trough across Central America and
adjacent waters S of 15N between 80W-90W. See the Special Features
section above for more information in regards to the heavy
rainfall across Central America. Additionally, scattered showers
are noted across the northern portion of the wave affecting Cuba
and adjacent waters.
The monsoon trough passes through the coastal sections of Senegal
and The Gambia near 13N16W to 11N32W. The ITCZ continues from
11N32W to 11N40W, then west of a tropical wave near 10N42W to
06N54W. Aside from the convection related to the tropical wave
described above, scattered showers are noted within 205 nm on
either side of the ITCZ.
GULF OF MEXICO…
A mid-level trough is moving eastward across the SE U.S. and
extends into the northeast Gulf. At the surface, a 1013 mb low is
analyzed near 29N87W with a trough extending from the low to
26N91W. North of this feature, a cold front extends across the
Gulf coast states. With this, scattered moderate convection
prevails along and south of the front reaching the Gulf waters
north of 26N between 88W-93W. The remainder of the basin remains
quiet with a surface ridge prevailing. Latest scatterometer data
depicts light to gentle winds across the Gulf.
The cold front across the south and southeast CONUS will reach
the Gulf northern waters on Thu morning where it will stall
by Fri before lifting north of the area on Sat morning. Scattered
moderate convection will continue across the NE waters tonight
and prevail over the northern basin through Sat. Moderate to fresh
SW winds are expected over the NE waters Thu through Sat
associated with the front. Winds will pulse to fresh over the
western Yucatan Peninsula adjacent waters each evening associated
with the diurnal surface trough.
Refer to the section above for details on the tropical waves
moving across the basin. Also, refer to the Special Features
section above for details about the convection occurring over the
southwest Caribbean and Central America.
An upper level ridge is centered over the northern Caribbean,
with an inverted mid-level trough over Cuba. This is igniting
moderate convection north of 20N between 78W-87W. Latest scatterometer
data depicts fresh to strong trades north of Colombia with
moderate to fresh trades across most of the central Caribbean.
Gentle to moderate trades are noted in the eastern and western
portions of the basin.
The tropical wave with axis near 85W will move out of the western
Caribbean tonight. The second tropical wave with axis along 65W
will move across the central Caribbean on Thu, and the western
Caribbean through Sat. The passage of the second wave along with
high pressure north of the area will continue to support generally
fresh to strong winds in the central and southwest Caribbean
through Fri night and in the NW Caribbean this weekend. No
tropical cyclone activity is expected during the next several
Refer to the section above for details on the tropical wave
moving across the basin.
As a mid-level trough exits the U.S. east coast, scattered
moderate convection will develop across the western Atlantic. At
this time, this activity is noted north of 30N and west of 78W. To
the south, a surface trough extends from 29N78W to 25N80W with
scattered showers. High pressure dominates the rest of the basin
anchored by a 1026 mb high near 33N49W. Latest scatterometer data
depicts moderate to fresh northerly winds off the coast of
Western Sahara and Mauritania.
Surface ridge will persist across the forecast waters through
Mon. This pattern will maintain mainly gentle to moderate winds
north of 22N, and moderate to fresh winds south of 22N through
most of the period. Strong winds are expected between Turks and
Caicos and Hispaniola through Mon. No tropical cyclone activity
is expected for the next several days.