000
AXNT20 KNHC 192320
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
720 PM EDT Fri May 19 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 1800 UTC surface analysis and satellite imagery through
2315 UTC.

...SPECIAL FEATURES...

Please refer to the METEO-FRANCE High Seas Forecast, listed on
the website: WWW.METEOFRANCE.COM/PREVISIONS-METEO-MARINE/BULLETIN/
GRANDLARGE/METAREA2. Frequent wind gusts to gale-force are
forecast for the area of AGADIR. These conditions will dissipate
during the next 6-12 hours. An earlier scatterometer pass
confirmed the presence of these winds.

...TROPICAL WAVES...

A tropical wave axis extends from 12N23W to 04N24W, moving west at
10-15 kt. Isolated showers prevail along the wave`s axis between
23W- 26W.

A tropical wave axis extends from 14N53W to 07N53W, moving west
at 10-15 kt. Moisture within the wave`s environment has decreased
significantly as noted in TPW imagery. No convection is related to
this wave at this time.

A tropical axis extends from 18N81W to 10N81W, moving west at
10-15 kt. The wave remains embedded within an area of deep-layer
moisture as depicted in TPW imagery. Scattered moderate convection
is observed on either side of the wave`s axis from 11N-15N
between 80W-84W.

...ITCZ/MONSOON TROUGH...

The Monsoon Trough enters the tropical Atlantic through Guinea
near 10N14W and continues to 07N21W. The ITCZ extends west of a
tropical wave from 06N26W to 03N38W to 00N50W. Outside of the
convection associated with the tropical wave, no significant
convective activity is noted at this time.

...DISCUSSION...

GULF OF MEXICO...

A broad area of high pressure prevails across the southeast CONUS
and Atlantic ocean, extending across the basin. This pattern is
producing moderate to fresh southeasterly winds across most of
the area. Fresh to locally strong easterly winds are noted just
north of the Yucatan Peninsula in association with a thermal
trough. A surface trough is analyzed over the southeast Gulf and
extends from 23N86W to the northeast coast of the Yucatan
Peninsula. This trough is expected to gradually shift westward
during the next 24 hours. Lower pressures prevail across Mexico
and the far west Gulf waters. Aloft, a short-wave trough is noted
across the north-central Gulf and is expected to cross north
Florida on Saturday. On this day, zonal flow will dominate the
Gulf region. The ridge will persist through Sunday with little
change in the weather pattern. A weak cold front is forecast to
move off the Texas coast by Sunday night.

CARIBBEAN SEA...

As previously mentioned, a tropical wave is moving across the
western Caribbean. Please refer to the TROPICAL WAVE section
above for details. A cut-off upper-level low continues to spin
over the Cayman Islands. A sharp trough extends from the low
toward the Gulf of Honduras and northern Central America. This
system has been responsible for large areas of strong thunderstorms
across the north-central Caribbean over the past several days.
Just south of the low is the axis of above mentioned tropical
wave. The combination of these two features is producing scattered
showers and a few thunderstorms affecting portions of Cuba, Cayman
Islands and Jamaica, as well as portions of Nicaragua, Costa Rica
and Panama. Abundant tropical moisture is forecast to persist
over the western Caribbean during the next 24 hours. High
pressure located north of the area combined with the
Colombian/Panamanian low are supporting strong to near gale-force
winds over the south-central Caribbean, including the Gulf of
Venezuela. A recent scatterometer pass indicate fresh to strong
winds across the remainder of the central Caribbean, with fresh
southeasterly winds just north of Jamaica. Fresh to strong trades
will persist over the central Caribbean during the upcoming
weekend.

...HISPANIOLA...

Upper-level flow has become more zonal across the island with a
break in the heavy rainfall from the past few days. Moisture
is forecast to diminish over the upcoming weekend as the upper-
level trough continues to drift eastward and the wind flow turns
more to the NW. As a result, expect scattered showers and
isolated thunderstorms due to local effects.

...ATLANTIC OCEAN...

A Gale Warning is in effect for the far east Atlantic waters.
Please refer to the SPECIAL FEATURES section above for details. A
ridge, with several high pressure centers along 31N/32N, dominates
the Atlantic Ocean. A surface trough extends from 26N60W to
21N62W. A recent scatterometer pass shows pretty well the wind
shift associated with this trough. Scattered showers are near the
trough axis. This feature is ahead of an upper-level trough that
extends from 31N61W to central Cuba into the cut-off low over the
Caribbean. Abundant mid-upper level moisture persists ahead of
this upper trough forecast to drift eastward.

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

$$

ERA