[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 271728
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
128 PM EDT Fri Jul 27 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 1200 UTC surface analysis and satellite imagery through
1715 UTC.

...TROPICAL WAVES...

A tropical wave extends across the east Atlantic with axis
from 05N-17N along 32W, moving W at 10-15 kt. The wave is being
covered by a Saharan air, which is suppressing convection mainly
north of 10N. Shallow moisture associated with the monsoon trough
and diffluence in the upper-levels support scattered showers
along the wave's axis south of 10N.

A tropical wave is over central Atlantic with axis extending from
05N-17N along 42W, moving westward at about 10 kt. Intrusion of
Saharan dry air and dust to the wave's environment is hindering
convection at this time.

A tropical wave is over the central Atlantic with axis extending
from 06N-19N along 57W, moving westward at about 10 kt. Similar
to the tropical wave to the east, Saharan dry air and dust is
inhibiting convection with this feature.

A tropical wave is over the west-central Caribbean with axis south
of 21N along 77W, moving W at 10 kt. Scattered showers are noted
along the southern portion of the wave where it meets the monsoon
trough S of 12N.

...MONSOON TROUGH/ITCZ...

The monsoon trough extends from the coast of Africa near 19N16W
to 06N38W. The ITCZ extends from 06N43W to 06N55W. Scattered
showers are noted along the monsoon trough between 22W-34W.

...DISCUSSION...

GULF OF MEXICO...

The Atlantic subtropical ridge extends its axis SW across the
basin, thus supporting light to gentle variable winds basin-
wide. A surface trough is moving over the Bay of Campeche
enhancing winds in this area to moderate levels. The trough will
then dissipate this afternoon. This feature will develop again
over the next several nights with winds increasing to locally
fresh at times. GOES-16 water vapor imagery at lower levels show
very dry air in the Gulf. Surface ridging will prevail across the
basin through the weekend. Scattered showers are likely over the
Bay of Campeche associated with a tropical wave that will move
into this region by Sunday.

CARIBBEAN SEA...

Shallow moisture in the northwest Caribbean with a divergent
environment aloft are supporting scattered showers within 90 nm
off the coast of Cuba. In the southwest Caribbean, the EPAC's
monsoon trough supports scattered showers south of 12N between
75W-83W. This activity is also related to a tropical wave,
currently extending along 77W. Refer to the section above for more
details. Isolated showers are occurring in the northern Leeward
Islands and the Virgin Islands being supported by diffluence aloft
associated to an upper-level low centered northeast of Puerto
Rico. A new tropical wave is forecast to move across the Lesser
Antilles tonight, and a second wave will enter the east Caribbean
by Sun night. Otherwise, fresh to strong winds are forecast for
the south-central basin through the weekend.

ATLANTIC OCEAN...

Three tropical waves are moving across the basin. Please refer to
the section above for more details. Diffluent flow between the
base of an upper-level trough over the southeast CONUS and a high
over the northern Bahamas continue to support scattered showers
and tstms north of 20N W of 70W. The upper-level trough will
prevail through today, enhancing shower and thunderstorm activity
over this area. Farther east, a middle level low just north of
Hispaniola supports a surface trough that extends from 25N66W to
22N68W. Scattered moderate convection is noted with this features
between 64W-70W. The Atlantic subtropical ridge dominates the
remainder of the basin being anchored by a 1029 mb high centered
near 37N53W. Surface ridging will dominate the central and eastern
Atlantic through the weekend providing stable and dry conditions.

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

$$

ERA
This weather bulletin was brought to you by:
www.nashvilleweather.net