AXNT20 KNHC 230528

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
128 AM 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 0000 UTC surface analysis and satellite imagery through 0515 UTC.


A 1007 mb low pressure center is near 18N87W. A surface trough extends from the NE Yucatan Peninsula near 22N87W to the low center to the N coast of Honduras near 16N86W. This system just east of Belize is producing a large area of cloudiness and showers extending from the northwestern Caribbean Sea across Cuba and into the Florida peninsula. Little development is expected during the next couple of days due to strong upper-level winds and proximity to the Yucatan Peninsula of Mexico. However, gradual subtropical or tropical development is possible late this week while the system moves slowly into the central or eastern Gulf of Mexico. Regardless of development, locally heavy rainfall is possible across western Cuba, the Cayman Islands, and much of Florida during the next several days. For more information on the heavy rain threat, please see products issued by your local weather office. There is a very low possibility of tropical storm formation over the next 24 hours. There is a medium chance for tropical formation within 5 days.


A tropical wave is along 41W, S of 10N, moving W 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.


The monsoon trough passes through the coastal sections of Guinea near 11N15W to 04N18W. The ITCZ continues from 04N18W to 01N30W to 02N40W. The ITCZ resumes W of the tropical wave near 02N43W and reaches the coast of Brazil near 00N50W. Isolated moderate convection is from 00N-04N between 02W-22W. Similar convection is from 05S-03N between 23W-30W. Scattered moderate to isolated strong convection is along the coast of Brazil from 02S-01N between 46W-51W.



10-15 kt E to SE surface return flow is over the Gulf of Mexico. Presently scattered showers are over portions of the Florida Peninsula, the Straits of Florida, and W Cuba.

An upper level trough is in place over the far E Gulf of Mexico and Florida. Upper level diffluence is E of the trough axis, over the W Atlantic. A second upper level trough has entered the NW Gulf. An upper level ridge is over the central Gulf in between the two troughs.

An Atlantic surface ridge extending into the northern Gulf of Mexico will shift eastward through Fri. An area of low pressure is expected to develop off the northern coast of Yucatan on Fri. The tropical low will move slowly northward in the eastern Gulf this weekend, with highest winds and seas east of the low.


Please read the Special Features section above. Clusters of scattered moderate convection is inland over Central America from the Yucatan Peninsula to Panama. An area of scattered moderate convection is S of Cuba from 16N-22N between 77W-83W.

An upper level ridge is over the W Caribbean W of 70W with considerable upper level moisture. An upper level trough is over the E Caribbean with strong subsidence E of 70W and N of 12N.

A surface ridge north of the area will maintain fresh trade winds in the central Caribbean through Thu, with strong winds expected along the northern coast of Colombia. A broad low near Belize will drift northward into the Gulf of Mexico through Fri. Fresh to strong SE winds and building seas are possible in the NW Caribbean Thu night and Fri as the low develops.


Scattered showers are over the W Atlantic W of 74W to include the Bahamas and Florida. A 1027 mb high is centered over the central Atlantic near 31N50W producing fair weather.

An E-to-W oriented ridge along 30N will support moderate to fresh trade winds south of 22N this week, with winds pulsing to strong N of Hispaniola at night. Winds and seas will diminish slightly Fri as the ridge shifts east. An area of low pressure in the Gulf of Mexico will increase SE winds west of 77W this weekend.

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

$$ Formosa