Tropical Weather Discussion
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AXNT20 KNHC 180444

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1244 AM EDT Wed Apr 18 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 0000 UTC surface analysis and satellite imagery through
0515 UTC.


The monsoon trough extends from the coast of Africa near 11N15W
to 03N18W. The ITCZ continues from 03N18W to 03N30W to the coast
of South America near 01S45W. Scattered moderate convection is
from 01N-04N between 14W-21W. Isolated moderate convection is from
03S-04N between 36W-50W.



A 1020 mb high centered over the north-east Gulf near 28N84W,
continues to produce generally fair weather with mostly clear
skies across the basin. 10-15 kt anticyclonic surface winds are
over the Gulf with seas building to 7 ft over the west Gulf. The
Yucatan Channel presently has seas 4-5 ft.

The 1020 mb high will shift eastward and weaken through mid week
ahead of the next cold front that will move into the northern Gulf
on Thursday. The front should stall from southwestern Florida to
south Texas Fri, before lifting north as a warm front over Texas
on Saturday. Another late-season cold front will be approaching
the northwestern Gulf on Sunday.


A surface trough is over the Gulf of Honduras and over
Honduras. Scattered showers are south of 19N and west of 84W.
More scattered showers are over central Hispaniola. Fresh to
strong northeasterly winds are over the northwest Caribbean.
Brisk easterly trade winds of 20-25 kt continue just off the
coasts of Colombia and Venezuela.

Farther east, scattered showers are advecting over the Leeward
Islands. NE to E swell to 8 ft continue in the tropical Atlantic
waters east of the Windward Islands.

The trough over the Gulf of Honduras is expected to move westward
to Guatemala Wed. A building ridge north of the region will cause
the area of winds and seas off Colombia and Venezuela to expand
in coverage across the south-central Caribbean and into the
southwestern Caribbean by late Wednesday through late Friday.
Strong winds are expected to continue off the coast of Colombia
through late Sat.


A stationary front extends from 32N65W to the south Bahamas near
22N73W. Scattered showers and a isolated thunderstorms are within
60 nm of the front. 10-15 kt winds are noted on both sides of the
front. Seas are 8 to 10 ft north of 29N, west of front to 73W.
Elsewhere over open waters, seas are generally 5 to 7 ft.

The front should weaken from 32N63W to south Bahamas by late Wed,
then dissipate on Thu as it lifts northward. Another cold front
will move off the Florida east coast late Thu and extend from
Bermuda to south Florida by late Fri, before stalling from 25N65W
to the Straits of Florida by late Sat.

Farther east, a 1028 mb high is over the central Atlantic near
35N46W. The tail-end of a cold front is over the east Atlantic
from 32N25W to 29N35W. Scattered showers are within 90 nm of the
front. Expect a large area of NW swell with wave heights of 8-15
ft to accompany this front covering a large portion of the area
north of 20N and east of 45W Wed through Friday. Seas will
gradually decay to below 8 ft Saturday.

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