AXNT20 KNHC 231647

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1247 PM EDT Fri Jun 23 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 1200 UTC surface analysis and satellite imagery through 1600 UTC.


An eastern Atlantic tropical wave has an axis that extends from 18N25W to 06N27W, moving westward at 20 kt. This wave is accompanied by Saharan dust over the northern portion, with scattered moderate convection over the southern portion from 07N to 11N between 24W and 28W.

A central Atlantic tropical wave has an axis that extends from 13N46W, through a 1012 mb low near 09N47W to 03N47W, moving westward at 15 to 20 kt. This wave is accompanied by scattered moderate convection within 120 nm of either side of the wave axis.

A tropical wave just crossed the Windward Islands last night and is now over the eastern Caribbean with an axis extending from 17N63W to 08N63W. Dry air at the mid to upper levels is inhibiting deep convection over much of the wave, with mainly scattered showers noted within 240 nm of either side of the wave axis north of 12N.

A tropical wave extends from the NW Caribbean near 21N87W to central America near 15N88W, to the eastern Pacific near 11N88W. This wave is interacting with an upper low to support scattered thunderstorms within 300 nm of the wave axis north of 16N.


The monsoon trough crosses the western Africa coast near 14N16W and extends to 09N25W. The ITCZ axis extends from 07N29W to 04N45W. Aside from convection associated with an eastern and central Atlantic tropical wave, scattered moderate convection is within 150 nm of either side of the ITCZ axis.



High pressure centered over the western Atlantic has a ridge axis that extends across the northern Gulf of Mexico, supporting moderate to fresh south to southeast winds and mainly fair weather over the basin today. The only exception is a band of moisture from the SW Gulf to near the mouth of the Mississippi, and moisture streaming northwest over over the SE Gulf producing scattered showers. Over the next 24 hours the northern portion of a tropical wave will interact with an upper low to produce scattered thunderstorms over the south central and southwest Gulf tonight and Saturday.


An upper level low is interacting with a tropical wave over the NW Caribbean to support scattered showers and thunderstorms, while another tropical wave has just entered the eastern Caribbean. Please see the tropical waves section for more details. Scattered thunderstorms south of 11N over the southwest Caribbean are associated with the monsoon trough. Mainly moderate to fresh trade winds cover the Caribbean today, except light winds south of 11N over the southwest Caribbean. Over the next 24 hours the western Caribbean wave will exit the basin. The eastern Caribbean wave will approach the central Caribbean with scattered showers.


Scattered showers in a band of low level moisture are passing across the island today. Another batch of showers are poised to reach the island tonight, with additional showers possible late Saturday as a tropical wave passes south of the island.


There are two tropical waves crossing the tropical north Atlantic basin. Please refer to the tropical waves section for more details. A surface trough extending from 28N57W to 24N55W is a surface reflection of an upper low centered near 25N53W. These features support scattered showers and thunderstorms from 22N to 27N between 49W and 57W. A dissipating stationary front void of convection extends from 31N35W to 30N44W. High pressure of 1021 mb centered near 30N67W has a ridge axis that extends west across north Florida, and northwestward from the high to another high centered near the Azores. This ridge dominates the remainder of the Atlantic discussion waters. Little change is expected over the next 24 hours.

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

$$ Latto