AXNT20 KNHC 112330
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
630 PM EST Wed Dec 11 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
GULF OF MEXICO GALE WARNING...
Northerly gales continue in the southwestern Gulf of Mexico behind
a cold front. The gale force winds are expected to continue south
of 21N and west of 94W through this evening before diminishing.
Sea heights of 12-16 ft are expected in the area. See the latest
NWS High Seas Forecast issued by the National Hurricane Center
under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for further details.
The monsoon trough passes through the coastal areas of Sierra
Leone near 08N13W to 06N18W. The ITCZ continues from 06N18W to
00N44W. Isolated to scattered moderate convection is seen within
170 nm of the monsoon trough and ITCZ between the west coast of
Africa and 36W.
GULF OF MEXICO...
See the Special Features section on information about the gale
As of 11/2100 UTC, the cold front extends west from Clearwater,
Florida near 28N83W to 25N90W, and stalls from that point to the
southern coast of Mexico near 18N94W. A pre-frontal trough extends
in the eastern Bay of Campeche from 19N91W to 23N91W. Scattered
thunderstorms are seen near the cold front from 23N-27N between
86W-92W. High pressure is quickly building in behind the front.
The latest scatterometer data depicts strong to gale force winds
covering the northern and western Gulf with light winds in the
The cold front will completely stall out tonight, then will
weaken and lift back to the NW-N through Friday night as low
pressure forms over the W central Gulf. This low will track NE
across the N central waters through early Saturday, with the
associated cold front sweeping across the eastern Gulf through
Saturday night. The front will leave behind a dissipating
boundary across the far SE Gulf on Sunday. High pressure will
build southward across the central and E Gulf in the wake of this
front with fresh to strong southerly flow setting up over the
western Gulf by late Sunday. Another cold front will move into
the NW Gulf Monday.
Deep layered ridging continues to cover the Caribbean. An upper
level low to the east of the Leeward Islands is bringing isolated
thunderstorms to those islands. Scattered showers cover the SW
Caribbean, S of 12N between 76W-83W. Otherwise, fair weather
covers the rest of the basin. The latest scatterometer data
depicts strong to near gale force winds north of Colombia, with
fresh to strong trades across the central and eastern Caribbean.
Gentle to moderate trades are noted in the NW Caribbean.
Winds and seas will gradually diminish across the region through
Friday as high pressure in the central Atlantic shifts eastward.
Trades will increase again in the central Caribbean early next
week as the pres gradient tightens. Moderate to fresh trades along
with moderate N to NE swell are expected over the Tropical N
Atlantic waters through the upcoming weekend and into early next
A cold front enters the western Atlantic from 31N76W to Cape
Canaveral, Florida near 28N81W. A pre-frontal trough extends from
31N75W to South Florida near 27N80W. Showers are seen within 150
nm of these features. Another trough is analyzed in the western
Atlantic from 23N69W to 31N66W with no significant convection
associated with it. An upper level low to the east of the Leeward
Islands is firing off scattered moderate convection from 17N-25N
between 54W-64W. High pressure dominates the eastern Atlantic
anchored by a 1041 mb high near 39N33W. The latest scatterometer
data depicts fresh to strong winds across the central Atlantic.
The cold front will reach from near 31N73W to West Palm Beach,
Florida by late tonight and from near 31N70W to 28N76W and
stationary to West Palm Beach on Thursday and gradually weaken
through Friday. Fresh to strong NE winds are expected N of the
front tonight through late Thursday night, while large seas are
expected over the waters N and NE of the Bahamas through early on
Friday. Fresh to strong southerly winds will develop over the far
N central waters beginning late on Friday night. These winds will
expand eastward through Saturday night ahead of the next cold
front forecast to move off the southeastern U.S. coast on Saturday.
This front will quickly move across the waters N of 27N through
Sunday night, with the fresh to strong winds lifting NE of the
area Sunday night. Return flow will develop early next week.
In the far northeastern Atlantic, near gale NE winds are expected
Thursday and Thursday night from the coast of Morocco through the