000 AXNT20 KNHC 230558 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT TUE APR 23 2013 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 SIERRA LEONE NEAR 7N13W...TO 4N14W AND 2N17W. THE ITCZ CONTINUES FROM 2N17W TO THE EQUATOR ALONG 26W... TO 1N35W...TO THE EQUATOR AGAIN ALONG 39W. CONVECTIVE PRECIPITATION...NUMEROUS STRONG TO THE EAST OF 10W TO THE SOUTH OF 5N4W 5N7W 2N10W... TO THE SOUTH OF 4N BETWEEN 20W AND 25W. SCATTERED MODERATE TO ISOLATED STRONG FROM 1N TO 6N BETWEEN 30W AND 34W. ...DISCUSSION... THE GULF OF MEXICO... MIDDLE LEVEL TO UPPER LEVEL TROUGH NORTHWESTERLY WIND FLOW COVERS THE AREA. AN EASTERN PACIFIC OCEAN MIDDLE LEVEL TO UPPER LEVEL RIDGE IS ALONG 14N103W 19N106W 22N110W. THE NORTHWESTERLY WIND FLOW MOVES FROM MEXICO INTO AND ACROSS THE GULF OF MEXICO. THE NORTHWESTERLY WIND FLOW IS MOVING TOWARD THE BASE OF THE 32N81W 29N79W 26N79W MIDDLE LEVEL TO UPPER LEVEL TROUGH. A SURFACE TROUGH IS ALONG 29N91W 26N89W. COMPARATIVELY DRIER AIR IN SUBSIDENCE IS TO THE NORTH OF 25N97W 24N90W 23N83W AT THE COAST OF CUBA. BROKEN TO OVERCAST LOW CLOUD CEILINGS ARE IN THE GULF OF MEXICO TO THE NORTH OF 26N TO THE EAST OF 90W. LOW CLOUD CEILINGS COVER THE TEXAS COASTAL PLAINS FROM THE MIDDLE GULF COAST SOUTHWARD. CLEAR SKIES/FAIR SKIES AT 12000 FEET OR LOWER ARE OBSERVED ELSEWHERE ALONG THE TEXAS GULF COAST TO BEAUMONT/PORT ARTHUR. PATTERSON MEMORIAL AIRPORT IN PATTERSON LOUISIANA IS REPORTING A LOW CLOUD CEILING OF 200 FEET. FAIR SKIES AT 12000 FEET OR LOWER/SCATTERED LOW CLOUDS ARE ELSEWHERE BETWEEN THE REST OF LOUISIANA AND THE FLORIDA PANHANDLE...AND FROM SARASOTA SOUTHWARD. LOW LEVEL CLOUD CEILINGS COVER THE REST OF FLORIDA BETWEEN THE FLORIDA PANHANDLE AND SARASOTA. FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE TO THE NORTH OF 27N TO THE WEST OF 88W... ICAO STATION KHQI IS REPORTING A VISIBILITY OF 1 MILE OR LESS WITH FOG. A LOW LEVEL CLOUD CEILING IS AT THE ICAO STATION KMYT. CLEAR SKIES/FAIR SKIES AT 12000 FEET OR LOWER ARE OBSERVED ELSEWHERE. THE CARIBBEAN SEA... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 18N51W IN THE ATLANTIC OCEAN TO 14N63W IN THE CARIBBEAN SEA...AND EVENTUALLY TO 12N75W. RAINSHOWERS ARE POSSIBLE TO THE EAST OF 68W. MIDDLE LEVEL TO UPPER LEVEL NORTHWESTERLY WIND FLOW MOVES FROM THE GULF OF MEXICO INTO AND ACROSS THE CARIBBEAN SEA. THE WIND FLOW REMAINS NORTHWESTERLY EVERYWHERE ELSE...AND IT EVENTUALLY MERGES WITH THE WIND FLOW THAT IS AROUND THE 18N51W 14N63W 12N75W TROUGH. UPPER LEVEL SOUTHWESTERLY WIND FLOW FROM SOUTH AMERICA IS TO THE SOUTH OF 15N60W 13N70W 12N78W. RAINSHOWERS ARE POSSIBLE ELSEWHERE FROM 16N TO 19N BETWEEN 70W AND 78W. THE MONSOON TROUGH IS ALONG 9N74W IN COLOMBIA... TO 9N78W IN PANAMA...BEYOND 8N81W IN PANAMA... INTO THE EASTERN PACIFIC OCEAN. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 7N TO 8N BETWEEN 76W AND 77W...SCATTERED MODERATE FROM 7N TO THE COAST OF PANAMA BETWEEN 81W AND 82W... AND WITHIN A 15 TO 30 NM RADIUS OF 9N84W ALONG THE COAST OF COSTA RICA. THE ATLANTIC OCEAN... A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH 32N81W NEAR SOUTHERN SOUTH CAROLINA TO 29N79W AND 26N79W. A SURFACE TROUGH EXTENDS FROM A 1015 MB LOW PRESSURE CENTER THAT IS NEAR 32N74W...TO GRAND BAHAMA ISLAND IN THE NORTHERN BAHAMAS...TO 25N81W JUST TO THE SOUTH OF THE FLORIDA KEYS. CONVECTIVE PRECIPITATION... WIDELY SCATTERED TO SCATTERED MODERATE AND ISOLATED STRONG TO THE NORTH OF 23N BETWEEN 70W AND 78W...INCLUDING ACROSS PARTS OF THE BAHAMAS. A SURFACE RIDGE PASSES THROUGH 32N59W TO 19N60W...JUST OUTSIDE THE NORTHEASTERN CORNER OF THE CARIBBEAN SEA. A MIDDLE LEVEL TO UPPER LEVEL TROUGH EXTENDS FROM A 32N35W CYCLONIC CIRCULATION CENTER TO A 30N40W CYCLONIC CIRCULATION CENTER... TO 18N51W...LEADING INTO THE CARIBBEAN SEA NEAR 14N63W AND 12N75W. A SURFACE TROUGH EXTENDS FROM A 1008 MB LOW PRESSURE CENTER THAT IS NEAR 31N35W TO 26N38W AND 23N43W. ISOLATED MODERATE CONVECTIVE PRECIPITATION IS TO THE NORTH OF 29N BETWEEN 26W AND 41W. RAINSHOWERS ARE POSSIBLE TO THE NORTH AND NORTHWEST OF THE LINE THAT PASSES THROUGH 32N26W 27N29W TO 20N40W AND 20N70W. AN EASTERN ATLANTIC OCEAN SURFACE RIDGE PASSES THROUGH 32N18W TO 28N21W...TO A 1015 MB HIGH PRESSURE CENTER THAT IS NEAR 19N33W...TO 10N49W. PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2... FOR MORE DETAILS ABOUT THE 1008 MB LOW PRESSURE CENTER THAT IS NEAR 32N34W. EXPECT 20 TO 25 KNOT NORTHERLY WINDS AND 9 TO 11 FOOT SEA HEIGHTS TO THE NORTH OF 28N BETWEEN 40W AND 44W. EXPECT ALSO WIND SPEEDS 20 KNOTS OR LESS AND SEA HEIGHTS REACHING 10 FEET TO THE NORTH OF 22N TO THE EAST OF 55W. A WEAKENING SURFACE TROUGH IS ALONG 31N75W 27N78W. EXPECT 20 TO 25 KNOT NORTHEASTERLY WINDS AND SEA HEIGHTS RANGING FROM 8 TO 12 FEET TO THE NORTH OF 28N TO THE WEST OF THE TROUGH. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT