[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 171746
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
146 PM EDT SAT SEP 17 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 1200 UTC surface analysis and satellite imagery through
1730 UTC.

...SPECIAL FEATURES...

Tropical Depression Julia is centered near 30.2N 76.2W at 17/1500
UTC or about 248 nm southeast of Charleston, South Carolina.
Julia continues to be stationary. Estimated minimum central
pressure is 1010 mb. Maximum sustained wind speed is 25 kt with
gusts to 35 kt. Scattered showers and isolated thunderstorms are
from 28N-32N between 70W-77W. Please see the latest NHC
Forecast/Advisory under the AWIPS/WMO headers MIATCMAT1/WTNT21KNHC
for more details.

Tropical Storm Karl is centered near 18.2N 38.2W at 17/0900 UTC
or about 660 nm west of the Cabo Verde Islands and about 1303 nm
east of the Leeward Islands moving west at 11 kt. Estimated
minimum central pressure is 1004 mb. Maximum sustained wind speed
is 40 kt with gusts to 50 kt. Scattered moderate convection is
from 18N-22N between 34W-39W. Please see the latest
Forecast/Advisory under the AWIPS/WMO headers MIATCMAT2/WTNT22
KNHC for more details.

Showers and thunderstorms have increased today near a broad
surface low associated with a tropical wave located between
Africa and the Cabo Verde Islands. The wave axis extends from
17N19W to a 1008 mb low near 12N19W to 10N19W. Environmental
conditions appear conducive for development, and a tropical
depression could form by the early next week while this system
moves westward to west-northwestward across the eastern tropical
Atlantic. This system is likely to bring heavy rain and gusty
winds to portions of the Cabo Verde Islands during the next couple
of days. At this time, a broad area of scattered moderate
convection prevails from 06N-18N between 17W-23W. This system has
a medium chance of tropical formation within the next 48 hours.

...TROPICAL WAVES...

A tropical wave extends across the central Tropical Atlantic
with axis from 21N55W to 12N56W, moving west 10 to 15 kt over the
past 24 hours. The wave coincides with a 700 mb inverted trough
depicted by model guidance. No convection is associated to this
feature at this time.

...ITCZ/MONSOON TROUGH...

The Monsoon Trough extends from the wave/low described above
centered near 12N19W to 13N33W. Aside from the convection related
to the tropical wave, scattered moderate convection is observed
within 200 nm south of the boundary between 21W-33W.

...DISCUSSION...

GULF OF MEXICO...

A mid-level trough is reflected at the surface extending from
27N95W to 30N93W. Scattered moderate convection prevails along
this trough between 91W-95W. To the southwest; a thermal surface
trough extends across the Bay of Campeche from 23N92W to 18N94W
with isolated convection. The remainder of the basin is under the
influence of a surface ridge anchored by a 1023 mb high centered
over North Carolina. Scatterometer data depicts southerly flow
across the northwest Gulf while a light to gentle easterly flow
prevails across the remainder of the area. A similar weather
pattern will prevail through the next 24 hours.

CARIBBEAN SEA...

An upper-level low is centered over the western Caribbean near
21N84W. Isolated convection prevails to the east of the upper low
between 75W-85W. Another upper-level low is entering the eastern
Caribbean, currently centered over the Leeward Islands. This low
is reflected at the surface as a trough that extends from 12N64W
to 21N60W. Scattered showers and thunderstorms extends are
observed along the trough and between 59W-64W. Scatterometer data
depicts gentle to fresh trades across the basin except fresh to
strong winds just north of the Colombian coast between 72W-78W.
Expect through the next 24 hours for the upper-level lows to
continue moving west enhancing convection. A tropical wave will
enter the eastern Caribbean with isolated convection possible.

...HISPANIOLA...

An upper-level ridge covers the island anchored over southwest
Haiti. With this, fair weather prevails across the area. These
conditions will continue through the next 24 hours. A tropical
wave that will enter the Caribbean tonight and will reach the
island by late Sunday night. Isolated convection is possible.

ATLANTIC OCEAN...

Tropical Storms Julia and Karl are moving across the basin.
Please see the Special Features section above for details. A
surface trough extends across the west-central Atlantic from
23N70W to 29N58W. Scattered showers and thunderstorms are within
100 nm on either side of the trough. The east Atlantic is
dominated by a surface ridge anchored by a 1030 mb high centered
east of the Azores near 38N23W. Expect through the next 24 hours
for Julia to continue weakening as it drifts northwest. Karl will
continue as a tropical storm while it moves west across the
central Atlantic. Little change is expected elsewhere.

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

$$

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