AXNT20 KNHC 161206
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
805 AM EDT Mon Jul 16 2018
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
SW Caribbean Sea gale warning: NE to E minimal gale force winds
near the coast of Colombia from 11N to 13N between 74W and 76W,
are forecast to diminish to strong to near gale force winds around
15Z this morning. The synoptic pattern set-up with strong high
pressure situated over the central Atlantic interacting with broad
low pressure over the SW Caribbean Seas and over northern S
America will allow for the minimal gale force winds to again
materialize Tue night and Wed night over the same area. Please
read the High Seas Forecast, under the AWIPS/WMO headers
HSFAT2/FZNT02 KNHC, for more details.
An eastern Atlantic tropical wave is along 37W/38 from 06N to
19N, moving westward at 10-15 kt. Widely scattered moderate
convection is from 06N-09N between 31W-35W. The GOES-16 RGB images
are depicting yet another massive plume of Saharan dry air and
associated dust following in behind the wave from 10N-28N.
An eastern Caribbean Sea tropical wave extends from 20N63W to
to 14N65W to inland S America to 10N66W, moving westward at 15-20
kt. This wave continues to be impacted by Saharan dust, suppressing
deep convection. Only isolated showers moving quickly westward
with the fresh easterly trades are seen within 120 nm of the wave
axis. This wave will move across the eastern Caribbean Sea through
Tue night, and the central Caribbean Wed through Thu.
A central Caribbean Sea tropical wave axis is along 82W S of 20N
to across central Panama and beyond, moving westward at 15 kt.
This wave is ill-defined at the surface. Its position is based on
extrapolation and from the latest 700 mb model diagnostics.
Scattered moderate convection is confined to within 60 nm of the
wave S of 13N.
A tropical wave has moved inland Central America, and is near
90W. Please refer to the eastern Pacific Tropical Weather
Discussion for the latest information on this wave as it moves
into the eastern Pacific Ocean today.
The monsoon trough extends from W Africa near 12N17W to 10N30W to
06N41W. The ITCZ begins near 06N41W and continues to South
America near 05N52W. Widely scattered moderate convection is from
03N-07N between 39W-52W.
GULF OF MEXICO...
A 1017 mb high centered over the central part of the basin near
26N90W is the main feature that is influencing the synoptic
pattern across the basin. Its associated gradient is allowing for
generally light to moderate anticyclonic flow to exist over the
gulf waters. Current NWS mosaic radar displays show scattered
showers and isolated thunderstorms over much of the eastern gulf
waters as well as over the eastern half of the central gulf. This
activity is moving westward under moderate upper northeast winds.
The activity should continue through tonight. Expect high
pressure to prevail across the northern waters through Thu. A
surface trough will move westward off the Yucatan Peninsula each
evening through Thu, enhancing nocturnal winds in the SW Gulf.
Please read the Special Features section for details about gale-
force winds near the coast of Colombia. Aside from the tropical
wave features as described above, an upper level low is noted on
water vapor imagery S of Cuba near 20N79W. Scattered showers are
also over the Leeward Islands. Fresh to strong E winds will
continue over the central Caribbean Sea through the middle of next
A weak surface trough extends from near 32N78W southwestward to
just east of NE Florida. Scattered showers and isolated
thunderstorms are seen north of 28N between 72W and 79W. Another
trough extends from near 32N60W to 29N75W. Scattered moderate
isolated strong convection along and within 90-120 nm SE of this
trough between 60W-64W while isolated showers and thunderstorms
are along and within 60 nm SE of the trough between 64W-75W.
This trough will slowly weaken through Tue as the upper trough
lifts to the NE away from it. High pressure will build in the wake
of the trough.
For additional information
please visit http://www.hurricanes.gov/marine