[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 140004
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
704 PM EST Fri Dec 13 2019

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
2350 UTC.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through the coastal border area of
Sierra Leone and Liberia to 06N16W. The ITCZ continues from
06N16W to 04N25W, 04N32W, and 04N39W. Precipitation:
Isolated moderate to locally strong are from 08N southward from
50W eastward.

GULF OF MEXICO...

A stationary front passes through 32N79W in the Atlantic Ocean,
to the NE Florida east coast near 30N81.5W, to the Florida
west coast near 29.5N83W, to a Gulf of Mexico 1011 mb low pressure
center that is near 29.5N87.5W, to 26N91W. A surface trough
extends from east Texas into the Gulf of Mexico near 26.5N92.5W.
Precipitation: isolated to widely scattered moderate and locally
strong from 22N northward from 86W eastward, including across
Florida. Upper level cyclonic wind flow covers the Gulf of Mexico
from 23N northward. The upper level cyclonic wind flow is
associated with the trough that has been moving the central U.S.A.
during the day on Friday.

The current stationary front, that is in the NE corner of the Gulf
of Mexico, will transition into a cold front, as it passes across
the eastern Gulf of Mexico through Saturday. The low pressure
center will move NE tonight. High pressure will shift eastward
across northern Florida on Sunday. The return wind flow will
strengthen in the western Gulf of Mexico, in advance of an
approaching cold front. This front will move off the Texas coast
on Monday, and extend from the Florida Panhandle to the SW Gulf of
Mexico on Tuesday. It is possible that gale-force northerly winds
may be to the west of the front, near the coast of Mexico, from late
Tuesday through Wednesday, as the front continues SE across the
Gulf of Mexico.

CARIBBEAN SEA...

Broad upper level cyclonic wind flow covers the Caribbean Sea from
10N to 20N from 70W eastward. A surface trough is along 67W/68W
from 17N southward. Comparatively drier air in subsidence covers
the Caribbean Sea from 20N southward from 84W eastward.
Precipitation: Isolated moderate from 10N to 14N between 50W and
60W, just to the east of the Caribbean Sea, in an area of an upper
level trough/cyclonic wind flow. Isolated moderate in the
Caribbean Sea, from 18N southward between 60W and 70W, and from
13N to 19N between 70W and 80W.

Broad surface low pressure covers the SW corner of the Caribbean
Sea. The monsoon trough passes through Costa Rica and northern
Panama, into northern Colombia along 10N. Satellite data and the
GFS forecast for 250 mb show upper level anticyclonic wind flow in
the SW corner of the Caribbean Sea. The GFS model forecasts for
500 mb and for 700 mb show cyclonic wind flow in the same area.
Precipitation: isolated moderate from 10N southward from 80W
westward. Rainshowers are possible elsewhere from 16N southward
from 78W westward, in broken to overcast low level and middle
level clouds, in trade wind flow.

The wind speeds and the sea heights will diminish across the
region tonight, gradually, as high pressure in the Atlantic Ocean
shifts eastward. The trade winds in the central and eastern
Caribbean Sea will increase early next week. Fresh trade winds and
moderate NE swell are expected in the Tropical N Atlantic Ocean
during the weekend.

ATLANTIC OCEAN...

A stationary front passes through 32N79W in the Atlantic Ocean,
to the NE Florida east coast near 30N81.5W, to the Florida west
coast near 29.5N83W, and into the N central Gulf of Mexico. A
second stationary front passes through 32N62W to 31N70W, and to
28N78W. Precipitation: widely scattered moderate to isolated
strong from 25N northward from 70W westward.

An upper level trough extends from a 31N38W cyclonic circulation
center, to 23N53W. One part of a trough continues from 23N53W to
12N55W. Another part of a trough extends from 23N53W into the SE
corner of the Caribbean Sea. A surface trough is along 31N49W
25N51W 18N53W. Precipitation: broken to overcast multilayered
clouds, and isolated to widely scattered moderate and locally
strong from 12N northward between 20W and 56W.

The current stationary front will dissipate tonight. Southerly
winds will increase tonight and on Saturday, in advance of a weak
cold front that is expected to move E across the northern waters
during the weekend. A stronger cold front will move off the
southeast U.S.A. coast, from Tuesday night through Wednesday
night, resulting in strong northerly winds and building seas.

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