[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 271802
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST THU DEC 27 2012

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 1715 UTC.

...THE ITCZ/THE MONSOON TROUGH...

THE MONSOON TROUGH PASSES THROUGH COASTAL LIBERIA NEAR 5N9W
TO 4N16W. THE ITCZ CONTINUES FROM 4N16W TO 3N27W AND 1N34W...
CROSSING THE EQUATOR ALONG 37W...TO 1S40W. CONVECTIVE
PRECIPITATION...SCATTERED STRONG FROM 5N TO 7N BETWEEN
13W AND 14W...AND FROM 3N TO 6N BETWEEN 30W AND 42W...
AND FROM 1N TO 2N BETWEEN 34W AND 37W.

...DISCUSSION...

THE GULF OF MEXICO...

BROAD MIDDLE LEVEL TO UPPER LEVEL WESTERLY WIND FLOW COVERS
THE AREA. THE DEEP LAYER TROUGH OF 24 HOURS AGO HAS MOVED
INTO THE WESTERN ATLANTIC OCEAN...JUST TO THE NORTH OF 32N.

A SURFACE RIDGE PASSES THROUGH MISSISSIPPI AND LOUISIANA...
INTO THE CENTRAL GULF OF MEXICO...AND THEN SHIFTING SLIGHTLY
SOUTHWESTWARD INTO THE SOUTHWESTERN CORNER OF THE AREA.
A 1020 MB HIGH PRESSURE CENTER IS IN MEXICO NEAR 20N98W.

COMPARATIVELY DRIER AIR ON WATER VAPOR IMAGERY IS TO THE NORTH
OF THE LINE THAT RUNS FROM 26N97W TO 25N90W TO 23N82W...IN THE
NORTHERN PART OF THE GULF OF MEXICO.

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...AND THE
OFFSHORE FORECAST...MIAOFFNT4...FOR MORE DETAILS ABOUT
A 30N92W 25N97W COLD FRONT AT 36 HOURS INTO THE FORECAST TIME.
EXPECT 20 TO 25 KNOTS AND SEAS HEIGHTS LESS THAN 8 FEET AT
36 HOURS...AND 25 TO 30 KNOT WINDS AND SEA HEIGHTS TO 9 FEET
AT 48 HOURS.

FROM THE WESTERN ATLANTIC OCEAN INTO
THE NORTHWESTERN CORNER OF THE CARIBBEAN SEA...

THE SOUTHERNMOST POINT OF A DEEP LAYER TROUGH REACHES 32N70W
IN THE WESTERN ATLANTIC OCEAN. MIDDLE LEVEL TO UPPER LEVEL
NORTHWESTERLY WIND FLOW CROSSES THE WESTERN ATLANTIC OCEAN...
AND PARTS OF THE NORTHEASTERN CARIBBEAN SEA...TOWARD THE
29N44W 19N44W 16N45W MIDDLE LEVEL TO UPPER LEVEL TROUGH.
THE TROUGH SUPPORTS A COLD FRONT THAT PASSES THROUGH 32N70W
30N72W...ACROSS ANDROS ISLAND IN THE BAHAMAS...REACHING THE
ATLANTIC OCEAN SIDE COAST OF CUBA NEAR 23N80W...INTO THE
NORTHWESTERN CARIBBEAN SEA NEAR 20N85W...THROUGH THE GULF
OF HONDURAS...INTO GUATEMALA NEAR 15N90W. CONVECTIVE
PRECIPITATION...BROKEN TO OVERCAST MULTILAYERED CLOUDS AND
SCATTERED MODERATE TO STRONG TO THE NORTH OF 30N BETWEEN 58W
AND 64W...ISOLATED MODERATE WITHIN 15 TO 30 NM ON EITHER SIDE
OF 26N73W 29N70W BEYOND 32N67W. NUMEROUS STRONG CONVECTIVE
PRECIPITATION WAS OCCURRING FROM 21N TO 23N BETWEEN 80W AND
82W IN AND AROUND CUBA AT 27/0915 UTC. THAT PRECIPITATION
HAS WEAKENED AND DISSIPATED SINCE THAT TIME. CONVECTIVE
PRECIPITATION IN THE CARIBBEAN SEA...ISOLATED MODERATE
TO LOCALLY STRONG FROM EASTERN HONDURAS NEAR 15N TO 21N
BETWEEN 82W AND 87W.

THE REST OF THE CARIBBEAN SEA...

BROAD UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS THE AREA.
A RIDGE RUNS ROUGHLY FROM LAKE MARACAIBO OF NORTHWESTERN
VENEZUELA TOWARD THE JAMAICA CHANNEL.

THE MONSOON TROUGH PASSES THROUGH 7N72W IN COLOMBIA...BEYOND
7N80W INTO THE EASTERN PACIFIC OCEAN. CONVECTIVE
PRECIPITATION...ISOLATED MODERATE HAS BEEN DEVELOPING AND
DISSIPATING...OFF AND ON...TO THE SOUTH OF 12N TO THE WEST
OF 80W...DURING THE LAST SIX HOURS OR SO. ISOLATED MODERATE
TO LOCALLY STRONG CONVECTIVE PRECIPITATION IS IN THE EASTERN
PACIFIC OCEAN FROM 5N TO 7N BETWEEN COLOMBIA AND 87W.

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...AND THE
OFFSHORE FORECAST...MIAOFFNT3...FOR MORE DETAILS ABOUT
20 TO 25 KNOT WINDS AND 11 TO 12 FOOT SEA HEIGHTS FROM
10N TO 17N BETWEEN 69W AND 82W FOR THE NEXT 48 HOURS.
EXPECT WIND SPEEDS TO 30 KNOTS NEAR THE COLOMBIA COAST
AT 24 HOURS.

THE REST OF THE ATLANTIC OCEAN...

A MIDDLE LEVEL TO UPPER LEVEL TROUGH EXTENDS FROM A 29N44W
CYCLONIC CIRCULATION CENTER...TO 19N44W...TO 16N45W. THE TROUGH
AND CYCLONIC CENTER SUPPORT A 1015 MB LOW PRESSURE CENTER THAT
IS NEAR 29N43W. ONE SURFACE TROUGH EXTENDS FROM THE LOW CENTER
TO 35N38W. A SECOND SURFACE TROUGH CURVES AWAY FROM THE 1015 MB
LOW CENTER TO 29N40W 25N40W 20N42W 14N46W 8N52W. CONVECTIVE
PRECIPITATION...SCATTERED TO NUMEROUS STRONG FROM 23N TO 27N
BETWEEN 37W AND 40W...SCATTERED MODERATE TO ISOLATED STRONG
ELSEWHERE TO THE NORTH OF 27N BETWEEN 35W AND 45W.

BROAD SURFACE ANTICYCLONIC WIND FLOW COVERS THE AREA THAT
IS TO THE NORTH OF 18N BETWEEN 50W AND 65W. A 1021 MB HIGH
PRESSURE CENTER IS NEAR 29N58W.

A SURFACE RIDGE PASSES THROUGH 32N25W TO 27N30W 22N33W AND
15N40W. BROAD SURFACE ANTICYCLONIC WIND FLOW COVERS THE
ATLANTIC OCEAN TO THE NORTH OF 15N TO THE EAST OF THE
29N40W 8N52W SURFACE TROUGH.

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2...FOR MORE
DETAILS ABOUT...20 TO 25 KNOT WINDS AND 9 FOOT SEA HEIGHTS
AROUND A 1015 MB LOW PRESSURE CENTER THAT IS NEAR 29N43W
AS INITIAL CONDITIONS. EXPECT 20 TO 30 KNOT WINDS AND 9 FOOT
SEA HEIGHTS WITH A 31N71W 23N80W COLD FRONT...AS INITIAL
CONDITIONS. EXPECT 25 TO 30 KNOT WINDS AND SEA HEIGHTS LOWER
THAN 8 FEET AT 48 HOURS...TO THE NORTH OF 29N TO THE WEST
OF 78W.

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$
MT





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