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Atlantic Tropical Weather Discussion (Text)

000
AXNT20 KNHC 051203
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST THU DEC 05 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1115 UTC.

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

THE MONSOON TROUGH PASSES THROUGH THE COASTAL SECTIONS OF  
SOUTHWESTERN GUINEA NEAR 9N13W TO 9N16W. THE ITCZ CONTINUES FROM 
9N16W TO 5N26W 4N40W 3N44W...AND 2N48W. CONVECTIVE 
PRECIPITATION...WIDELY SCATTERED MODERATE TO ISOLATED STRONG 
FROM 3N TO 12N BETWEEN 23W AND 50W. ISOLATED MODERATE ELSEWHERE 
TO THE SOUTH OF 13N BETWEEN AFRICA AND 60W.

...DISCUSSION...

THE GULF OF MEXICO...

MIDDLE LEVEL TO UPPER LEVEL ANTICYCLONIC WIND FLOW SPANS THE 
GULF OF MEXICO. A RIDGE EXTENDS FROM THE ISTHMUS OF TEHUANTEPEC 
OF SOUTHERN MEXICO BEYOND SOUTH CENTRAL LOUISIANA. COMPARATIVELY 
DRIER AIR IN SUBSIDENCE...AS SEEN IN WATER VAPOR 
IMAGERY...COVERS THE GULF OF MEXICO...TO THE SOUTH OF 25N97W 
27N91W 26N86W 26N83W. HIGH LEVEL MOISTURE IS TO THE NORTH OF THE 
25N97W 26N83W LINE.

FOR THE OFFSHORE OIL PLATFORM SITES THAT ARE TO THE NORTH OF 27N 
TO THE WEST OF 88W...

LOW CLOUD CEILINGS ARE OBSERVED AT THE FOLLOWING ICAO 
STATIONS...KVAF...KEIR...KATP...KMYT...KMDJ...KDLP...AND KATP. 
VISIBILITIES OF 3 MILES OR LESS ARE OBSERVED AT KBQX...KATP... 
KSPR...KEIR...KMYT...KMDJ...KDLP...AND KAXO. FAIR SKIES/CLEAR 
SKIES ARE BEING REPORTED ELSEWHERE ACROSS THE AREA AT OR LOWER 
THAN 12000 FEET.

FOR THE COASTAL PLAINS OF THE U.S.A. FROM TEXAS TO FLORIDA...

LOW CLOUD CEILINGS COVER COASTAL TEXAS. VISIBILITIES RANGE FROM 
TWO MILES OR LESS WITH FOG FROM THE SOUTHEASTERN PART OF THE 
HOUSTON METROPOLITAN AREA TO GALVESTON AND THE ANGLETON-LAKE 
JACKSON AREA...PALACIOS...AND PORT LAVACA. MCALLEN TEXAS IN THE 
DEEP SOUTH ALSO IS REPORTING A VISIBILITY OF ONE MILE WITH FOG. 
LOW CLOUD CEILINGS COVER THE LOUISIANA COASTAL PLAINS... 
INCLUDING AROUND THE LAKE PONTCHARTRAIN AREA. VISIBILITIES OF 2 
TO 3 MILES OR LOWER WITH FOG ARE IN THE SOUTHEASTERN PART OF THE 
STATE. LOW CLOUD CEILINGS...FOG WITH VISIBILITIES OF 2 MILES OR 
LESS...AND LIGHT RAIN ARE IN THE MISSISSIPPI COASTAL PLAINS... 
INTO ALABAMA ALSO. LOW CLOUD CEILINGS...VISIBILITIES OF 2 MILES 
OR LESS WITH FOG AND LIGHT RAIN ARE IN THE FLORIDA PANHANDLE... 
REACHING TALLAHASSEE. A MIDDLE LEVEL CLOUD CEILING COVERS PERRY 
FLORIDA. BROOKSVILLE IS REPORTING A VISIBILITY OF ONE MILE AND 
FOG. THE VISIBILITY AT THE TAMPA EXECUTIVE GENERAL AIRPORT... 
ICAO KVDF...HAS VARIED FROM 1 MILE OR LESS WITH FOG TO 4 MILES 
DURING THE NIGHT AND EARLY MORNING HOURS OF TODAY.

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...AND 
THE OFFSHORE FORECAST...MIAOFFNT4/FZNT24 KNHC...FOR MORE DETAILS 
ABOUT THE 36 HOUR FORECAST OF A COLD FRONT 30N92W 26N97W. EXPECT 
NORTH WINDS 20 TO 25 KNOTS AND SEA HEIGHTS LOWER THAN 8 FEET TO 
THE NORTHWEST OF THE FRONT.

...HISPANIOLA...

MIDDLE LEVEL TO UPPER LEVEL NORTHWESTERLY WIND FLOW COVERS THE 
AREA. SCATTERED LOW CLOUDS ARE BEING REPORTED ACROSS HISPANIOLA. 
LIGHT RAIN HAS BEEN REPORTED DURING THE LAST FEW OBSERVATIONS IN 
THE EASTERN PART OF THE DOMINICAN REPUBLIC. COMPARATIVELY DRIER 
AIR IN SUBSIDENCE...AS SEEN IN WATER VAPOR IMAGERY...COVERS THE 
AREA. 

A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH THE ATLANTIC 
OCEAN NEAR 32N56W TO 26N59W AND 17N63W. THE TROUGH SUPPORTS A 
COLD FRONT THAT PASSES THROUGH 32N52W 27N56W 24N59W. A SURFACE 
TROUGH CONTINUES ALONG 24N59W TO 20N61W...18N64W...ALONG 
NORTHERN PUERTO RICO...THROUGH THE MONA PASSAGE...TO 16N70W. 
CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG 
FROM 17N TO 20N BETWEEN 60W AND PUERTO RICO. WIDELY SCATTERED 
MODERATE FROM 13N TO 17N BETWEEN 64W AND 74W. 

24-HOUR RAINFALL TOTALS IN INCHES FOR THE PERIOD ENDING AT 
04/1200 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND 
PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...WERE 1.46 FOR ST. 
THOMAS...0.68 IN SAN JUAN PUERTO RICO...AND 0.17 IN TRINIDAD.

THE GFS FORECAST FOR 250 MB SHOWS THAT NORTHWESTERLY-TO-
NORTHERLY WIND FLOW WILL PASS ON TOP OF HISPANIOLA DURING THE 
NEXT 48 HOURS. CYCLONIC WIND FLOW FROM A TROUGH WILL COVER THE 
CARIBBEAN SEA FROM HISPANIOLA EASTWARD. THE GFS FORECAST FOR 500 
MB SHOWS THAT NORTHWESTERLY WIND FLOW WILL PASS ON TOP OF 
HISPANIOLA FOR THE FIRST 12 HOURS OF THE 48 HOUR FORECAST 
PERIOD. THE WIND FLOW WILL SHIFT...AFTER THE FIRST 12 HOURS... 
FROM NORTHWESTERLY...TO NORTHERLY...AND TO NORTHEASTERLY...AND 
CONTINUE AS NORTHEASTERLY FOR THE REST OF THE 48 HOUR FORECAST 
PERIOD. THE NORTHEASTERLY WIND FLOW WILL BE ASSOCIATED WITH 
ANTICYCLONIC WIND FLOW...WITH A NORTHERN BAHAMAS-TO-YUCATAN 
PENINSULA RIDGE. THE GFS FORECAST FOR 700 MB SHOWS THAT 
NORTHEASTERLY WIND FLOW WILL CROSS HISPANIOLA FOR THE ENTIRE 
TIME OF THE FORECAST PERIOD. THE NORTHEASTERLY WIND FLOW WILL BE 
ASSOCIATED WITH AN ATLANTIC OCEAN-TO-FLORIDA RIDGE.

THE REST OF THE CARIBBEAN SEA...

MIDDLE LEVEL TO UPPER LEVEL NORTHWESTERLY WIND FLOW CROSSES 
HISPANIOLA...AND IT COVERS THE REST OF THE CARIBBEAN SEA TO THE 
EAST OF 70W.

MIDDLE LEVEL TO UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS MUCH 
OF THE REST OF THE CARIBBEAN SEA...TO THE WEST OF 70W. THIS 
ANTICYCLONIC WIND FLOW IS ASSOCIATED WITH THE RIDGE THAT EXTENDS 
FROM THE ISTHMUS OF TEHUANTEPEC OF SOUTHERN MEXICO BEYOND EAST 
TEXAS/WESTERN LOUISIANA.

THE MONSOON TROUGH IS ALONG 8N BETWEEN 75W IN COLOMBIA...BEYOND 
84W IN THE EASTERN PACIFIC OCEAN. CONVECTIVE PRECIPITATION... 
RAINSHOWERS ARE POSSIBLE TO THE SOUTH OF 11N TO THE WEST OF 
COLOMBIA...IN THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA.

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...AND 
THE OFFSHORE FORECAST...MIAOFFNT3/FZNT23 KNHC...FOR MORE DETAILS 
ABOUT THE NORTHEAST TO EAST WINDS 20 TO 25 KNOTS AND SEA HEIGHTS 
TO 8 FEET FROM 11N TO 14N BETWEEN 72W AND 77W. A SECOND AREA OF 
INTEREST CONSISTS OF THE 18 HOUR FORECAST OF NORTHEAST TO EAST 
WINDS 20 TO 25 KNOTS AND SEA HEIGHTS LOWER THAN 8 FEET FROM 18N 
TO 20N BETWEEN 72W AND 80W INCLUDING IN THE WINDWARD PASSAGE.

THE REST OF THE ATLANTIC OCEAN...

A MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS 
NEAR 33N27W IN THE NORTHEASTERN ATLANTIC OCEAN. A TROUGH EXTENDS 
FROM THE 33N27W CENTER TO 22N28W 15N31W AND 13N38W. A 998 MB LOW 
PRESSURE CENTER IS NEAR 33N27W. A SURFACE TROUGH SPIRALS AWAY 
FROM THE 998 MB LOW CENTER...PASSING THROUGH 32N22W TO 27N21W 
AND 21N28W. CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO  
ISOLATED STRONG TO THE NORTH OF 26N BETWEEN THE CANARY ISLANDS 
AND 30W.

A MIDDLE LEVEL TO UPPER LEVEL TROUGH PASSES THROUGH THE ATLANTIC 
OCEAN NEAR 32N56W TO 26N59W AND 17N63W. THE TROUGH SUPPORTS A 
COLD FRONT THAT PASSES THROUGH 32N52W 27N56W 24N59W. A SURFACE 
TROUGH CONTINUES ALONG 24N59W TO 20N61W...18N64W...ALONG 
NORTHERN PUERTO RICO...THROUGH THE MONA PASSAGE...TO 16N70W. 
CONVECTIVE PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG 
FROM 17N TO 20N BETWEEN 60W AND PUERTO RICO. WIDELY SCATTERED 
MODERATE FROM 13N TO 17N BETWEEN 64W AND 74W...FOR THE CARIBBEAN 
SEA. SCATTERED MODERATE TO ISOLATED STRONG WITHIN 60 NM TO 120 
NM ON EITHER SIDE OF 20N60W 27N52W BEYOND 32N48W...FOR THE 
ATLANTIC OCEAN.

A SURFACE RIDGE PASSES THROUGH 32N43W TO 18N44W. THE RIDGE IS 
BETWEEN THE 998 MB LOW CENTER AND THE 32N52W 24N59W COLD FRONT.

A 1025 MB HIGH PRESSURE CENTER IS NEAR 35N66W. A SURFACE RIDGE 
EXTENDS FROM THE 1025 MB HIGH CENTER TO THE NORTHERN 
BAHAMAS...TO THE WESTERN TIP OF CUBA...TO THE YUCATAN PENINSULA. 
THIS RIDGE IS TO THE WEST OF THE 32N52W 24N59W COLD FRONT.

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT1/FZNT01 KWBC...FOR 
MORE DETAILS ABOUT NORTHWEST TO NORTH WINDS 20 TO 25 KNOTS AND 
SEA HEIGHTS 12 TO 19 FEET TO THE NORTH OF 27N TO THE EAST OF 
38W. EXPECT ALSO WINDS 20 KNOTS OR LESS AND SEA HEIGHTS 8 TO 12 
FEET ELSEWHERE N OF 21N E OF A LINE FROM 31N47W TO 25N42W TO 
21N35W...EXCEPT SEA HEIGHTS 10 TO 15 FEET TO THE NORTH OF 25N TO 
THE EAST OF 40W. THE 18-HOUR FORECAST CONSISTS OF A COLD FRONT 
FROM 31N47W TO 24N55W. NORTH TO NORTHEAST WINDS 20 TO 25 
KNOTS...EXCEPT NW TO N WINDS N OF 28N WITHIN 360 NM W OF 
FRONT...AND SEA HEIGHTS 8 TO 10 FEET TO THE NORTH OF 27N TO THE 
WEST OF THE FRONT TO 60W. THE 12-HOUR FORECAST CONSISTS OF 
NORTHEAST WINDS 20 TO 25 KNOTS AND SEA HEIGHTS LOWER THAN 8 FEET 
TO THE SOUTH OF 21N BETWEEN 72W AND 74W.     

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

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MT