Tropical Weather Discussion
Issued by NWS

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
865
AXNT20 KNHC 240009
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
809 PM EDT Wed May 23 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 1800 UTC surface analysis and satellite imagery through
2315 UTC.

...SPECIAL FEATURES...

A broad surface low centered over the southeastern Yucatan
Peninsula has become better defined since yesterday, and it
continues to produce a large area of cloudiness and showers
extending from the northwestern Caribbean Sea across Cuba into the
Florida Straits. Continued slow development of this system is
possible during the next couple of days as it drifts northward
near the Yucatan Peninsula. Thereafter, environmental conditions
are forecast to become more conducive for development, and a
subtropical or tropical depression is likely to form this weekend
over the eastern or central Gulf of Mexico. Regardless of
development, locally heavy rainfall is possible across western
Cuba and the Cayman Islands during the next few days, and over
much of Florida and the northern Gulf Coast during the weekend.
For more information on the heavy rain threat, please see products
issued by your local weather office. The chance for tropical
cyclone formation during the next 48 hours is low. The chance for
tropical cyclone formation during the next 5 days, on the other
hand, is high.

...TROPICAL WAVES...

A tropical wave is along 45W S of 10N moving westward at 10 to 15
knots. This wave is embedded in a sharp 700 mb trough. Scattered
showers are within 120 nm of the wave axis.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through the coastal sections of Guinea
near 10N13W to 05N17W. The ITCZ continues from 05N17W to 00N28W
to 01N44W. The ITCZ continues W of the tropical wave from 01N46W
to the coast of Brazil near 00N50W. Isolated moderate convection
is from 01N-06N between 08W-25W. Widely scattered moderate
convection is from 05S-04N between 25W-35W.

...DISCUSSION

GULF OF MEXICO...

A surface ridge extends from an Atlantic Ocean high centered near
32N42W to the NE Gulf of Mexico. 10-15 knot E to SE winds are over
the Gulf. An upper level trough is over the Gulf of Mexico with
axis along 90W. Upper level moisture is over the Gulf except over
the SW Gulf where strong subidence is noted. Isolated moderate
convection is over the central Gulf from 24N-27N between 85W-91W.
More isolated moderate convection is over the NW Gulf from 25N-31N
berween 91W-95W.

The surface ridge is forecast to shift eastward through early
Thursday. Broad surface low pressure, that is just to the north of
Belize, is expected to develop and move to the northern coast of
the Yucatan Peninsula on Friday morning. The low pressure center
will then move northward, slowly, to the eastern Gulf of Mexico
this weekend. Expect near gale-force winds and associated seas to
the east of the low pressure center.

CARIBBEAN SEA...

Please read the Special Features section above. Scattered moderate
convection is over the NW Caribbean Sea from 18N-22N between
82W-88W. Scattered moderate convection is inland over Central
America from the Yucatan Peninsula to Panama. Elsewhere, 15-20
knot tradewinds are over the central and E Caribbean.

An upper level trough extends from an Atlantic Ocean 23N55W
cyclonic circulation center, through 17N58W, to the coast of
Venezuela near 11N63W. Comparatively drier air in subsidence is
apparent in water vapor imagery from 11N to 20N between 52W and
70W, in the Caribbean Sea and in the Atlantic Ocean. Upper level
cyclonic wind flow covers the Caribbean Sea from 70W eastward. No
significant deep convective precipitation is apparent in satellite
imagery.

ATLANTIC OCEAN...

Scattered showers are over the Bahamas. A 1028 mb high is
centered over the central Atlantic near 32N42W producing fair
weather.

An upper level trough extends from a 23N55W cyclonic circulation
center, through 17N58W, to the coast of Venezuela near 11N63W.
Comparatively drier air in subsidence is apparent in water vapor
imagery from 11N to 20N between 52W and 70W, in the Caribbean Sea
and in the Atlantic Ocean.

Expect moderate to fresh trade winds south of 27N this week, with
winds pulsing to strong N of Hispaniola at night on Wednesday and
on Thursday. The winds will diminish slightly on Friday, as the
ridge shifts eastward. A developing area of low pressure in the
Gulf of Mexico for this weekend will increase SE winds west of 77W
from Friday through Sunday.

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

$$
Formosa



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.