[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 152359
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
805 PM EDT MON AUG 15 2016

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 tropical wave is over the Eastern Atlantic just west of the
Cabo Verde Islands and extends from 16N25W to 06N26W.  A 1008 mb
low pressure has developed along the wave axis near 9N26W.
Clusters of  moderate isolated strong convection are noted
within about 210 nm NW quadrant of low center.  The wave is in a
moist environment with pretty good 700 mb signature.
Environmental conditions are expected to be conducive for
development during the next few days, and a tropical depression
is likely to form while the system moves west-northwestward to
northwestward toward the central tropical Atlantic. Latest
Tropical Weather Outlook gives this system a medium change of
tropical development through 48 hours, and a high change of
tropical formation through 5 days.

...TROPICAL WAVES...

Another tropical wave is over the central tropical Atlantic and
extends from 20N46W to 09N47N moving W at 20 kt. The wave is in
a moist environment as depicted by the SSMI Total Precipitable
Water Imagery, however, dry air with Saharan dust is wrapping
around the west side of the wave. The wave has a classic V-
structure on satellite imagery, with a swirl of low clouds along
the wave axis near 18N. The wave is well defined at 700 mb.
Isolated to scattered showers are observed mainly ahead of the
wave.

A tropical wave is over the Eastern Caribbean and extends from
western Puerto Rico to the coast of Venezuela near 11N67W,
moving W at 15-20 kt.  The San Juan Doppler radar indicates
scattered showers and isolated tstms in association with this
wave.  Some shower activity is also seen across the Caribbean
waters,  on either side of the wave axis. A low amplitude
northward bulge of moisture that extends to about 16N is noted
on the TPW product. Moisture associated with the wave is
forecast to remain south of 20N as the wave continues west
through the central Caribbean tonight and Tuesday.

...ITCZ/MONSOON TROUGH...

The Monsoon Trough extends from the African coast near 15N17W to
a 1008 mb low pressure located near 09N26W to 08N38W. The ITCZ
continues from 08N38W to 08N47W to the coast of South America
near 07N58W. Besides the convection associated with the tropical
waves, scattered moderate convection is from 7N-10N between 34W-
36W, and from 06N-08N between  47W-60W.

...DISCUSSION...

GULF OF MEXICO...

A stationary front extends over Central Texas . A band of
showers and tstms is related to the front. Flash flood threat
persists along the Texas coast. The mosaic Doppler radar from
the SE U.S. shows scattered showers and tstms across the NW Gulf
in a southerly wind flow. Similar convective activity is noted
over Florida but in an easterly wind flow.  A surface ridge
dominates the Gulf region. The most recent scatterometer data
provide observations of fresh to strong southerly winds across
the western periphery of the ridge, but particularly N of 20N
between 91W-94W. Similar wind speeds are also noted across the
Straits of Florida from the east. A surface trough is analyzed
over the Yucatan Peninsula where scattered moderate to isolated
strong convection is occurring. A thermal trough is forecast to
develop over the Yucatan Peninsula during the afternoons,then
move NW across the SW Gulf during the overnight hours and
dissipate during the early morning hours.  In the upper levels,
an upper level high is centered over E Texas helping to induce
convection. An upper level low is centered over the central Gulf
near 26N88W with a trough extending SW to the Bay of Campeche.
Upper diffluence ahead of the trough supports the convection
over the Yucatan peninsula.  Abundant mid-upper level moisture
is over the Gulf.

CARIBBEAN SEA...

A tropical wave is over the Eastern Caribbean. Please, see the
tropical waves section above. Elsewhere, scattered moderate
convection is over the NW Caribbean,  south of Isle of Youth
Cuba,  from 18N-21N  between 81W-84W.  Similar convection is
over the SW Caribbean near the coast of Nicaragua. Scatterometer
data and buoys observations indicate fresh to strong  tradewinds
over the central Caribbean with the strongest winds along the
coast of N Colombia. These winds are forecast to persist through
mid-week, increasing to near gale force  along the NW coast of
Colombia during the overnight and early morning hours through
Wednesday night. Aloft, a ridge dominates the western part of
the basin while an inverted trough extends from Haiti to
Colombia. Another ridge from the Atlantic covers the eastern
Caribbean.

...HISPANIOLA...

Scattered showers and isolated tstms were noted over Hispaniola
late this afternoon likely associated with the local effects.
Similar weather conditions are expected on Tuesday. A tropical
wave is forecast to move across the island tonight and tomorrow
and could enhance the convective activity during the afternoon
and early evening hours. Computer model indicates that the
convection associated with the tropical wave should remain south
of the island over the next 24 hours.

ATLANTIC OCEAN...

Two tropical waves are moving westward between the coast of
Africa and the Lesser Antilles. Please, see the tropical waves
section above. High pressure dominates the entire area with an E
to W ridge axis along 30N-31N. The pressure gradient between the
ridge and lower pressure over western Africa is producing near
gale force winds from the NE across the Canary Islands. A recent
scatterometer data confirmed the presence of these winds. The
strongest winds are occurring between islands.  The ridge will
meander just N of the forecast area through Thursday.

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

$$
GR
NThis weather bulletin was brought to you by:
www.nashvilleweather.net