000
AXNT20 KNHC 130605
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
205 AM EDT FRI APR 13 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 0515 UTC.

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

THE MONSOON TROUGH PASSES THROUGH COASTAL GUINEA-BISSAU AND 
GUINEA NEAR 11N15W TO 6N19W AND 2N23W. THE ITCZ CONTINUES FROM 
2N23W TO THE EQUATOR ALONG 29W. THE ITCZ CONTINUES ALONG THE 
EQUATOR BETWEEN 29W AND 41W...AND THEN IT GOES INTO NORTHEASTERN
BRAZIL NEAR 2S46W. SCATTERED TO NUMEROUS STRONG CONVECTIVE 
PRECIPITATION FROM 4N TO 7N BETWEEN 10W AND 13W. ISOLATED 
MODERATE CONVECTIVE PRECIPITATION IS ELSEWHERE TO THE SOUTH
OF 6N.

...DISCUSSION...

THE GULF OF MEXICO...
THE UPPER LEVEL TROUGH FROM 24 HOURS AGO HAS LEFT FROM THE GULF 
OF MEXICO COMPLETELY. IT IS NOW IN THE ATLANTIC OCEAN MOVING 
TOWARD 70W. RESULTANT UPPER LEVEL WESTERLY WIND FLOW COVERS THE 
AREA. AN UPPER LEVEL SHORTWAVE TROUGH HAS MOVED FROM CENTRAL 
TEXAS INTO THE EASTERN PART OF LOUISIANA SINCE 12/1200 UTC.
A SURFACE RIDGE EXTENDS FROM A 1020 MB HIGH PRESSURE CENTER THAT 
IS NEAR 30N87W...JUST TO THE SOUTH OF THE WESTERN FLORIDA 
PANHANDLE...TO THE SOUTHWESTERN CORNER OF THE AREA NEAR 20N97W...
IN THE COASTAL PLAINS OF MEXICO. THE MARINE CONDITIONS ARE FOR
20 KNOT EASTERLY TO SOUTHEASTERLY WINDS AND SEA HEIGHTS LESS 
THAN 8 FEET IN THE NORTHWESTERN AND WESTERN SECTIONS OF THE
AREA DURING THE FIRST 24 HOURS OF THE FORECAST PERIOD. THE WIND 
SPEEDS IN THE NORTH CENTRAL SECTIONS INCREASE WITH TIME AFTER
24 HOURS. PLEASE REFER TO THE MIAOFFNT4 AND MIAHSFAT2 BULLETINS
FOR MORE DETAILS.

THE CARIBBEAN SEA...
THE BASE OF THE WESTERN ATLANTIC OCEAN TROUGH THAT IS MOVING 
TOWARD 70W IS MOVING THROUGH THE AREA THAT IS CLOSE TO THE 
WINDWARD PASSAGE...NEAR THE SOUTHEASTERN BAHAMAS...SOUTHEASTERN
CUBA...AND HISPANIOLA. RAINSHOWERS ARE POSSIBLE FROM THE GREATER 
ANTILLES TO 21N BETWEEN 64W AND 71W. UPPER LEVEL SOUTHWESTERLY 
WIND FLOW COVERS THE REST OF THE AREA. THE SURFACE PRESSURE 
GRADIENT IS COMPARATIVELY WEAK IN THE CARIBBEAN SEA. RAINSHOWERS 
ARE POSSIBLE TO THE SOUTH OF 18N BETWEEN 65W AND 73W. THE MARINE 
CONDITIONS ARE FOR A FORECAST FOR THE NEXT 12 HOURS OF 
NORTHEASTERLY WINDS 20 KNOTS AND SEA HEIGHTS LESS THAN 8 FEET. 
THE FORECASTS FOR 24 HOURS AND 48 HOURS PUT NORTHEASTERLY WINDS 
OF 20 KNOTS AND SEA HEIGHTS LESS THAN 8 FEET...TO THE NORTH OF 
17N...INCLUDING IN THE WINDWARD PASSAGE. PLEASE REFER TO THE 
MIAOFFNT3 AND MIAHSFAT2 BULLETINS FOR MORE DETAILS. 

THE ATLANTIC OCEAN...
AN UPPER LEVEL TROUGH PASSES THROUGH 32N72W TO 25N72W TO THE 
WINDWARD PASSAGE SUPPORTS THE COLD FRONT THAT PASSES THROUGH
32N63W 26N70W 25N75W...ACROSS THE NORTHERN BAHAMAS TO 27N80W.
A PRE-FRONTAL TROUGH IS WITHIN 90 TO 150 NM TO THE SOUTHEAST OF 
THE FRONT TO THE NORTH OF 26N...AND WITHIN 150 TO 250 NM TO THE 
SOUTHEAST OF THE FRONT FROM 22N TO 26N. SCATTERED MODERATE TO 
ISOLATED STRONG CONVECTIVE PRECIPITATION IS WITHIN 150 NM ON 
EITHER SIDE OF 21N63W 26N61W BEYOND 32N57W. RAINSHOWERS ARE 
POSSIBLE FROM THE GREATER ANTILLES TO 21N BETWEEN 64W AND 71W.
BROAD SURFACE ANTICYCLONIC WIND FLOW IS TO THE NORTH OF 14N 
BETWEEN AFRICA AND 60W. A 1032 MB HIGH PRESSURE CENTER IS NEAR 
35N37W. AN UPPER LEVEL TROUGH IS ALONG 28N23W 22N31W TO 8N35W.

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

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MT