000
AXNT20 KNHC 121804
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
105 PM EST WED JAN 12 2011

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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND 
RADAR.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1715 UTC.

...THE ITCZ...

04N ALONG THE PRIME MERIDIAN...4N10W...4N21W 2N39W...CROSSING
THE EQUATOR ALONG 45W...INTO NORTHEASTERN BRAZIL NEAR 1S48W.
BROKEN TO OVERCAST MULTILAYERED CLOUDS AND DISORGANIZED ISOLATED 
MODERATE RAINSHOWERS TO LOCALLY STRONG THUNDERSTORMS ARE WITHIN
120 NM TO 150 NM ON EITHER SIDE OF THE LINE 1N5W 5N25W 4N41W 
2N51W. STRONG RAINSHOWERS AND THUNDERSTORMS ARE IN BRAZIL
FROM 1S TO THE EQUATOR BETWEEN 47W AND 51W.

...DISCUSSION...

THE GULF OF MEXICO...

AN UPPER LEVEL SHORTWAVE TROUGH IS DIGGING THROUGH SOUTHERN 
CALIFORNIA AND SOUTHERN ARIZONA INTO NORTHWESTERN MEXICO.
IT IS MOVING TOWARD AN AREA OF ALREADY-EXISTING WESTERLY WIND 
FLOW THAT IS MOVING ACROSS MEXICO ALONG 27N...TOWARD THE GULF
OF MEXICO. THAT AREA OF WIND FLOW CONTINUES ACROSS THE NORTHERN
GULF WATERS AND EVENTUALLY MOVES NORTHEASTWARD BEYOND 
NORTHEASTERN FLORIDA INTO THE ATLANTIC OCEAN. A SEPARATE MASS
OF UPPER LEVEL MOISTURE IS MOVING FROM THE EASTERN PACIFIC OCEAN
TOWARD THE WESTERN MEXICO COAST FROM 16N TO 24N. UPPER LEVEL 
MOISTURE THAT CURRENTLY COVERS THE YUCATAN PENINSULA ALSO IS 
MOVING NORTHEASTWARD...BEYOND FLORIDA TO THE SOUTH OF 28N...
INTO THE ATLANTIC OCEAN. A SHARP SURFACE RIDGE PASSES THROUGH 
TEXAS NEAR 30N98W INTO MEXICO NEAR 24N99W INTO THE ISTHMUS OF 
TEHUANTEPEC. GALE-FORCE WINDS ARE OBSERVED IN THE GULF OF 
TEHUANTEPEC AND SURROUNDING WATERS. A STORM IS FORECAST IN THE 
SAME AREA DURING THE NEXT 24 HOURS. A COLD FRONT PASSES OVER 
ANDROS ISLAND IN THE BAHAMAS...GRAZING THE GULF OF MEXICO COAST 
OF CUBA THAT IS NEAR 23N83W...REACHING THE NORTHWESTERN CORNER
OF THE YUCATAN PENINSULA...TO THE EASTERN ISTHMUS OF 
TEHUANTEPEC. BROKEN TO OVERCAST MULTILAYERED CLOUDS AND POSSIBLE 
RAINSHOWERS ARE FROM GUATEMALA TO 24N BETWEEN 86W IN THE GULF OF 
MEXICO AND 94W.
 
THE CARIBBEAN SEA...

AN UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 17N79W.
UPPER LEVEL CYCLONIC FLOW COVERS THE AREA TO THE SOUTH OF 18N TO 
THE WEST OF 74W. BROAD UPPER ANTICYCLONIC FLOW COVERS THE REST 
OF THE AREA. BROAD SURFACE CYCLONIC FLOW COVERS THE AREA...
ESPECIALLY TO THE SOUTH OF 17N BETWEEN 69W AND NICARAGUA.
THIS IS EVIDENT IN THE VISIBLE SATELLITE IMAGERY. RAINSHOWERS
ARE POSSIBLE IN CLUSTERS OF LOW LEVEL CLOUDS THAT ARE TO THE 
SOUTH OF 14N TO THE EAST OF 70W...FROM 14N TO 17N BETWEEN 60W 
AND 62W...FROM 13N TO 16N BETWEEN 69W AND 75W...FROM EASTERN
HONDURAS AND NORTHEASTERN NICARAGUA TO 17N BETWEEN 81W AND 85W.
 
THE ATLANTIC OCEAN...

UPPER LEVEL SOUTHWESTERLY WIND FLOW IS MOVING ON TOP OF THE AREA 
OF THE COLD FRONT THAT JUST PASSED THROUGH THE GULF OF MEXICO
DURING THE LAST 24 HOURS TO 48 HOURS. THE FRONT PASSES THROUGH
32N68W...TO ELEUTHERA ISLAND AND ANDROS ISLAND IN THE BAHAMAS...
GRAZING THE GULF OF MEXICO COAST OF CUBA THAT IS NEAR 23N83W... 
TO THE NORTHWESTERN CORNER OF THE YUCATAN PENINSULA...TO THE 
EASTERN ISTHMUS OF TEHUANTEPEC. BROKEN TO OVERCAST MULTILAYERED 
CLOUDS AND POSSIBLE RAINSHOWERS ARE FROM GUATEMALA TO 24N 
BETWEEN 86W IN THE GULF OF MEXICO AND 94W. AN UPPER LEVEL TROUGH 
PASSES THROUGH 33N35W TO 28N36W TO 20N37W. THIS TROUGH SUPPORTS 
THE COLD FRONT THAT REACHES 31N37W. A STATIONARY FRONT CONTINUES 
FROM 31N37W TO 27N45W. A REMNANT CLOUD LINE CONTINUES FROM 
27N45W TO 24N60W TO 23N70W. ISOLATED MODERATE RAINSHOWERS ARE TO 
THE NORTH OF 30N BETWEEN 30W AND 34W. BROKEN LOW LEVEL TO MIDDLE 
LEVEL CLOUDS AND POSSIBLE PRECIPITATION ARE WITHIN 45 NM TO 75 
NM ON EITHER SIDE OF 30N35W 26N42W 24N52W 23N60W. ONE SURFACE 
RIDGE PASSES THROUGH 32N20W TO 27N30W TO 26N40W. SURFACE 
ANTICYCLONIC FLOW MOVES AROUND A 1026 MB HIGH PRESSURE CENTER 
THAT IS NEAR 28N56W. 

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

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MT