Tropical Weather Discussion

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Tropical Weather Discussion (NHC/TPC):
NWS National Hurricane Center Miami FL
1233 PM EDT Wed Mar 22 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 
1515 UTC.

...ITCZ/MONSOON TROUGH...
The Monsoon Trough extends from the African coast near 07N12W to 
02N22W. The Intertropical Convergence Zone axis extends from 
02N22W to the Equator near 26W. Scattered moderate and isolated
strong convection is S of 07N between 09W-20W. Scattered moderate
convection is S of 03N between 20W-33W...and S of 02N between 
40W-52W.

...DISCUSSION...

GULF OF MEXICO...
NW flow aloft prevails over the Gulf providing dry air and stable
conditions that filter to the surface in the form of a ridge 
anchored by a 1021 mb high centered near 27N90W. The ridge 
extends eastward very narrowly across the southern Florida
peninsula and Florida Keys into portions of the SW North Atlc. 
Gentle to moderate anticyclonic winds accompany the ridge as noted
on recent ASCAT data. The high is forecast to remain nearly 
stationary across the central Gulf waters with little change in 
the overall wind pattern through late Wednesday night. By 
Thursday...the ridge will weaken slightly and merge NE with a
eastern CONUS high pressure system. E-SE winds are forecast to 
increase into fresh to strong levels Thursday night into Friday as
an area of low pressure develops across the Front Range and 
central Plains.
 
CARIBBEAN SEA...
Broad upper level troughing is noted on water vapor imagery over
the NW Caribbean while southwesterly flow aloft to the east of 
the troughing prevails over the central and eastern Caribbean. 
Dry and stable air overall is providing for a lack of any 
significant deep convection and mostly tranquil surface conditions
this afternoon. A few areas of isolated showers however are noted
on satellite imagery across the far southwestern waters S of 17N 
W of 80W...including inland portions of Honduras...Nicaragua...and
Costa Rica. A frontal boundary terminates N of Hispaniola near
20N72W and is providing isolated showers across the island 
adjacent coastal waters N of 17N between 70W-77W. 
Otherwise...moderate to occasional fresh trades prevail and are 
expected to persist through Thursday night.

...HISPANIOLA...
The tail end of a warm front extends from the central Atlc near 
23N62W SW to the northern coast of Hispaniola near 20N71W. Low- 
level moisture convergence associated with the front continues to 
provide focus for isolated showers generally N of 17N between 
70W-77W...including portions of the adjacent coastal waters. The 
front is expected to gradually lift northward and become absorbed
by a cold front expected to impact the SW North Atlc waters by
Thursday. Any lingering remnant boundary or surface troughing 
will provide a slight probability of isolated shower activity 
through the remainder of the week.

ATLANTIC OCEAN...
Broad middle to upper level troughing is noted on water vapor
imagery over the SW North Atlc generally W of 65W in response to 
a middle to upper level trough progressing over the NE CONUS. A
shortwave mid-level trough is noted in the vicinity of 33N74W
supporting a 1008 mb low centered near 34N75W. The associated cold
front extends westward to the coast of South Carolina with
scattered showers and tstms occurring N of 31N between 73W-76W.
Farther east...another middle to upper level trough axis extends N
of 32N along 42W over the central North Atlc. The associated cold
front extends to 32N47W then becomes stationary into the
discussion area SW to 23N62W then transitions into a warm front to
the Turks and Caicos islands and the northern coast of Hispaniola
near 20N71W. Scattered showers and isolated tstms are occurring N
of 29N within 150 nm E of the front. Similar convection is
occurring along and N of the warm front from 20N-25N between
63W-73W. Finally...the remainder of the eastern Atlc is under the
influence of another surface ridge anchored by a 1035 mb high 
centered N of the Azores near 40N28W. A dissipating cold front
extends across far NW Africa near 32N09W to 30N18W to 32N30W.
Little sensible weather is occurring with this cold front.

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

$$
Graphical representation of waves, etc. on this image (NCEP/OPC) [more].
Various tropical satellite imagery available here

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