[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 250603
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
103 AM EST FRI NOV 25 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 0000 UTC surface analysis and satellite imagery through
0545 UTC.

...SPECIAL FEATURES...

Otto weakened to a tropical storm over NW Costa Rica at 25/0300
UTC. Tropical Storm Otto is centered near 10.9N 85.6W or about 16 nm
north of Liberia, Costa Rica moving west at 11 kt. Estimated
minimum central pressure is 990 mb. Maximum sustained wind speed
is 60 kt with gusts to 75 kt. Scattered heavy showers and isolated
tstms are from 10N-12N between 84W and 87W. Scattered heavy
showers are also affecting the region from 13N-18N between 80W and
87W. Total rainfall of 6 to 12 inches, with isolated amounts of
15 to 20 inches, can be expected across northern Costa Rica and
southern Nicaragua through tonight. These rains will likely result
in life-threatening flash floods and mudslides. Recent reports
from amateur radio operators indicate that mudslides are occurring
over portions of northern Costa Rica. Please see latest NHC
Intermediate Public Advisory under AWIPS/WMO headers
MIATCPAT1/WTNT31 KNHC and the full Forecast/Advisory under
AWIPS/WMO headers MIATCMAT1/WTNT21 KNHC for more details.

...ITCZ/MONSOON TROUGH...

The monsoon trough extends across Africa into the east Tropical
Atlantic near 07N12W to 05N16W where it transitions to the ITCZ
that continues along 5N30W to 8N40W to 8N44W. Isolated showers are
within 120 nm either side of the ITCZ axis.

...DISCUSSION...

...GULF OF MEXICO...

With westerly flow aloft and gentle easterly to northeasterly wind
at the surface across the northern Gulf, a front continues to
stall from SE Louisiana near 29N90W to 27N92W. Except for low
level moisture being advected from the Caribbean to the Bay of
Campeche, CIRA layer precipitable water and water vapor imagery
show deep layer dry air elsewhere, thus maintaining fair weather
conditions. Surface ridging ahead of the front and anchored by a
1027 mb high in the NW Atlantic provide with gentle easterly flow
N of 26N while the latest scatterometer data show fresh to strong
E flow across the Florida Straits and the SE basin. Moderate N-NE
flow is within 120 nm off the western coast of the Yucatan
Peninsula. The stationary front will extend along the northern
Gulf coastline through Friday morning when it will transition to a
cold front. The newly formed cold front will reach from northern
Florida to central Texas early Saturday.

...CARIBBEAN SEA...

The outer rainbands associated with now Tropical Storm Otto are
affecting the NW Caribbean basin S of 19N W of 80W where scattered
heavy showers are observed, including inland Honduras and
Nicaragua. For further details about Otto see special features
above. Diffluent flow associated with an upper ridge anchored over
northern Venezuela along with abundant low to middle moisture
across the region support scattered heavy showers and isolated
tstms in the central Caribbean S of 18N between 70W and 80W.
Similar convection is in the SE basin S of 12N. The tail of a cold front
extending from the central Atlantic to NE Hispaniola adjacent
waters support cloudiness across the Island with possible isolated
showers. High pressure over the NW Atlantic will continue to
support fresh to strong northeast winds over the northern-central
and northwest basin through Saturday before sunrise.

...HISPANIOLA...

The tail of a cold front extending from the central Atlantic to
NE Hispaniola adjacent waters support cloudiness across the Island
with possible isolated showers. Showers are expected for the NE
portion of the Island through Saturday.

...ATLANTIC OCEAN...

A middle level low in the NW Atlantic with associated trough
extending S-SW to near 30N continue to support a cold front from
30N47W to 24N55W where it starts to dissipate to NE Hispaniola
adjacent waters near 19N68W. Ahead of the front, two surface
troughs are observed; one extending from 27N48W to 20N47W and the
other from 28N38W to 20N37W. Isolated showers are within 120 nm
either side of the westernmost trough. Scattered to isolated
showers are within 150 nm either side of the second trough.
Surface ridging and fair weather is W of the cold front as well as
N of 16N E of 30W. Otherwise, in the tropics, a surface trough is
along 15N44W to 8N45W with scattered to isolated showers within
120 nm either side of its axis. Scattered moderate convection is
NE of this trough from 13N to 18N between 28W and 40W. The cold
front is forecast to dissipate Saturday morning. A new cold front
will move into SW N Atlantic waters Saturday evening.

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

$$
RAMOS
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