Tropical Weather Discussion
Issued by NWS
AXNT20 KNHC 181001
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
601 AM EDT Tue Apr 18 2017
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
The Monsoon Trough extends across the western Africa coast near
11N16W and continues to 02N21W. The Intertropical Convergence
Zone continues from 02N21W to 00N49W. Scattered moderate to
isolated strong convection prevails along and within 150 nm on
either side of the Monsoon Trough between 12W-22W.
...GULF OF MEXICO...
A 1023 mb high is centered over the west Atlantic near 29N67W
with a surface ridge extending across northern Florida to the
northern Gulf of Mexico along 29N. A 1019 mb surface high was
analyzed over the Florida Panhandle near 30N84W. With this, a
gentle to moderate anticyclonic flow prevails across the basin,
with strongest winds over the Straits of Florida and the southeast
Gulf south of 26N east of 86W. Latest radar imagery depicts
scattered moderate convection developing along the eastern coast
of Mexico reaching portions of southern Texas. This activity could
move offshore through the night, affecting the northwestern Gulf
waters west of 94W. The nocturnal thermal trough that develops
every night is once again over the Bay of Campeche, extending
from 22N91W to 19N93W. Little change in marine conditions is
expected during the next 24-48 hours, with a nocturnal surge of
moderate to fresh winds expected west of the Yucatan Peninsula in
the overnight hours. The surface high will remain over land during
the next 24 hours.
Gentle to moderate trades prevail across the basin, except
pulsing moderate to fresh northeast winds off the coast of
Colombia and across the approach to the Windward Passage.
Scattered moderate convection is weakening over western Colombia
to across Panama and southern Costa Rica. In the upper levels, a
trough extends its axis roughly along 80W. With this, cloudiness
and scattered convection prevails east of the trough over portions
of eastern Hispaniola and Puerto Rico, as well as their adjacent
waters. Expect little change over the next 24-48 hours.
Scattered showers are moving across the eastern portion of the
island supported by an upper-level trough to the west, and with
upper-level diffluence which has been over the island. This
activity should diminish towards the morning, but similar
conditions are possible this afternoon/evening.
A 1023 mb high is centered over the W Atlantic near 29N67W. To
the east, a gale-force low is centered to the north of the area
supporting near-gale wind north of 26N between 43W-53W. Seas in
this area are ranging between 15-22 ft. Its associated dissipating
cold front has transitioned into a surface trough extending from
31N34W to 19N40W. Another surface trough extends from 15N54W to
15N61W. No significant convection is related to these features at
this time. The gale-force low is forecast to move southeast
during the next 24 hours, reaching 31N42W by this afternoon.
Expect for the surface troughs to dissipate by that time. Little
change is expected elsewhere.
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