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Atlantic Tropical Weather Discussion (Text)

000
AXNT20 KNHC 070604
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 AM EST SAT DEC 07 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.

...SPECIAL FEATURE...                                           

A GALE WARNING EXISTS IN THE ATLANTIC OCEAN...NEAR A COLD FRONT  
FROM 31N36W TO 23N42W TO 20N53W THEN SHEAR LINE TO 18N68W. 
EXPECT NORTHWEST TO NORTH WINDS 30 TO 35 KNOTS AND SEA HEIGHTS 
13 TO 20 FEET TO THE NORTH OF 27N BETWEEN 43W AND 50W. THE REST 
OF THE FORECAST FOR THE MARINE CONDITIONS...ELSEWHERE W OF FRONT 
TO 54W N OF 25N NW TO N WINDS 20 TO 30 KT. SEAS 8 TO 12 FT IN 
PRIMARILY NE SWELL. N OF 26N WITHIN 120 NM E OF FRONT S TO SW 
WINDS 20 TO 25 KT. SEAS 8 TO 10 FT. N OF SHEAR LINE TO 25N 
BETWEEN 53W AND 66W NE WINDS 20 TO 25 KT. SEAS 8 TO 11 FT. 
REMAINDER AREA W OF FRONT TO 70W...EXCEPT N OF 27N W OF 60W 
WINDS 20 KT OR LESS. SEAS 8 TO 11 FT IN NE SWELL.

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

THE MONSOON TROUGH PASSES THROUGH THE COASTAL SECTIONS OF SIERRA 
LEONE AND GUINEA NEAR 9N13W TO 9N16W AND 8N19W. THE ITCZ 
CONTINUES FROM 8N19W TO 7N20W 4N30W AND 2N43W. CONVECTIVE 
PRECIPITATION...ISOLATED MODERATE TO LOCALLY STRONG TO THE SOUTH 
OF 10N BETWEEN AFRICA AND 60W.

ONE ATLANTIC OCEAN SURFACE TROUGH IS ALONG 40W/41W FROM 9N TO 
13N. CONVECTIVE PRECIPITATION...ISOLATED MODERATE TO LOCALLY 
STRONG FROM 11N TO 20N BETWEEN 35W AND 41W.

A SECOND ATLANTIC OCEAN SURFACE TROUGH IS ALONG 49W/50W FROM 9N 
TO 14N. CONVECTIVE PRECIPITATION...WIDELY SCATTERED MODERATE TO 
ISOLATED STRONG FROM 12N TO 16N BETWEEN 46W AND 50W.

...DISCUSSION...

THE GULF OF MEXICO...

A COLD FRONT PASSES THROUGH SOUTHERN MISSISSIPPI...INTO THE WEST 
CENTRAL GULF OF MEXICO...TO MEXICO NEAR 19N97W. A STATIONARY 
FRONT IS IN MEXICO FROM 19N97W TO 22N100W...25N100W AND BEYOND 
THE TEXAS BIG BEND. BROKEN TO OVERCAST MULTILAYERED CLOUDS ARE 
TO THE NORTHWEST OF THE 31N87W 25N93W 19N96W.

MIDDLE LEVEL TO UPPER LEVEL ANTICYCLONIC WIND FLOW SPANS THE 
GULF OF MEXICO. A RIDGE PASSES THROUGH 32N75W IN THE ATLANTIC 
OCEAN...TO 27N82W ALONG THE SOUTHWESTERN COAST OF FLORIDA... 
SOUTHWESTWARD BEYOND THE YUCATAN PENINSULA OF MEXICO. 
COMPARATIVELY DRIER AIR IN SUBSIDENCE...AS SEEN IN WATER VAPOR 
IMAGERY...COVERS THE GULF OF MEXICO. 

AN ATLANTIC OCEAN 1028 MB HIGH PRESSURE CENTER IS NEAR 33N65W. A 
SURFACE RIDGE EXTENDS FROM THE 1028 MB HIGH CENTER...TO 
30N75W...ACROSS FLORIDA ALONG 28N...TO 27N84W AND 26N87W IN 
THE GULF OF MEXICO NEAR 25N92W.

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

LOW CLOUD CEILINGS COVER MANY OF THE ICAO STATIONS. VISIBILITIES 
OF THREE MILES OR LESS WITH FOG CONTINUE AT THE EASTERN END OF 
THE AREA...AND AT THE WESTERN END OF THE FORECAST AREA.

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

LOW CLOUD CEILINGS COVER COASTAL TEXAS BEHIND THE CURRENT 
WESTERN GULF OF MEXICO COLD FRONT. LIGHT RAIN IS OCCURRING IN 
THE DEEP SOUTH OF TEXAS. THE LOW CLOUD CEILINGS CONTINUE INTO 
SOUTHERN LOUISIANA. LIGHT RAIN IS OBSERVED AROUND LAKE 
PONTCHARTRAIN. THE LOW CLOUD CEILINGS AND LIGHT RAIN CONTINUE 
INTO MISSISSIPPI AND ALABAMA. LOW CLOUD CEILINGS AND RAIN 
CONTINUE IN THE FLORIDA PANHANDLE. VISIBILITIES OF 3 MILES OR 
LESS WITH FOG ARE BEING REPORTED FROM PERRY TO TALLAHASSEE TO 
APALACHICOLA. LOW CLOUD CEILINGS ARE OBSERVED FROM THE TAMPA 
METROPOLITAN AREA TO SARASOTA. 

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...AND 
THE OFFSHORE FORECAST...MIAOFFNT4/FZNT24 KNHC...FOR MORE DETAILS 
ABOUT THE COLD FRONT FROM 29N90W TO 26N93W AND 19N97W. EXPECT 
NORTH WINDS 20 TO 25 KNOTS...EXCEPT WIND SPEEDS TO 30 KNOTS 
WITHIN 60 NM OF THE COAST FROM 22N TO 26N. SEA HEIGHTS 8 TO 10 
FEET. 

...HISPANIOLA...

MIDDLE LEVEL TO UPPER LEVEL NORTHEASTERLY WIND FLOW COVERS THE 
AREA. BROKEN LOW CLOUDS ARE IN THE EASTERN PART OF THE DOMINICAN 
REPUBLIC. SCATTERED LOW CLOUDS ARE BEING REPORTED ELSEWHERE 
ACROSS HISPANIOLA. COMPARATIVELY DRIER AIR IN SUBSIDENCE...AS 
SEEN IN WATER VAPOR IMAGERY...COVERS THE AREA. 

A MIDDLE LEVEL TO UPPER LEVEL TROUGH EXTENDS FROM AN ATLANTIC 
OCEAN 19N61W CYCLONIC CIRCULATION CENTER...INTO THE SOUTHEASTERN 
CORNER OF THE CARIBBEAN SEA INTO NORTHERN VENEZUELA. CONVECTIVE 
PRECIPITATION...SCATTERED MODERATE TO ISOLATED STRONG FROM 16N 
TO 21N BETWEEN 52W AND 64W...FROM THE ATLANTIC OCEAN INTO THE 
CARIBBEAN SEA. RAINSHOWERS ARE POSSIBLE ELSEWHERE IN THE 
CARIBBEAN SEA TO THE SOUTH OF 20N. 

THE 24-HOUR RAINFALL TOTAL IN INCHES FOR THE PERIOD ENDING AT 
05/1200 UTC...ACCORDING TO THE PAN AMERICAN TEMPERATURE AND 
PRECIPITATION TABLES...MIATPTPAN/SXCA01 KNHC...WAS 1.65 IN SAN 
JUAN PUERTO RICO...AND 1.44 IN ST. THOMAS. 

THE GFS FORECAST FOR 250 MB SHOWS THAT NORTHERLY-TO-
NORTHEASTERLY WIND FLOW WILL PASS ON TOP OF HISPANIOLA DURING 
THE NEXT 48 HOURS. CYCLONIC WIND FLOW FROM A TROUGH WILL COVER 
THE CARIBBEAN SEA TO THE EAST OF 80W. THE GFS FORECAST FOR 500 
MB AND FOR 700 MB SHOWS THAT NORTHEASTERLY TO EASTERLY WIND FLOW 
WILL PASS ON TOP OF HISPANIOLA FOR THE NEXT 48 HOURS.

THE REST OF THE CARIBBEAN SEA...

MIDDLE LEVEL TO UPPER LEVEL CYCLONIC WIND FLOW COVERS THE 
CARIBBEAN SEA TO THE EAST OF 70W. MIDDLE LEVEL TO UPPER LEVEL 
ANTICYCLONIC WIND FLOW COVERS THE CARIBBEAN SEA FROM 
70W WESTWARD.

THE MONSOON TROUGH IS ALONG 9N73W IN COLOMBIA...7N80W AND 7N83W 
IN THE ATLANTIC OCEAN. CONVECTIVE PRECIPITATION...SCATTERED TO 
NUMEROUS STRONG FROM 9N TO 10N WITHIN 30 NM ON EITHER SIDE OF 
81W IN THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA. NUMEROUS 
STRONG IN THE EASTERN PACIFIC OCEAN FROM 5N TO 8N BETWEEN 78W 
AND 83W.

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...AND 
THE OFFSHORE FORECAST...MIAOFFNT3/FZNT23 KNHC...FOR MORE DETAILS 
ABOUT....NORTHEAST WINDS 20 TO 25 KNOTS AND SEA HEIGHTS TO 8 
FEET TO THE SOUTHWEST OF THE WINDWARD PASSAGE. A SECOND AREA OF 
INTEREST CONSISTS OF NORTHEAST TO EAST WINDS 20 TO 25 KNOTS AND 
SEA HEIGHTS 8 TO 11 FEET FROM 11N TO 18N BETWEEN 70W AND 77W. 
WINDS 20 KNOTS OR LESS AND SEA HEIGHTS 8 TO 10 FEET FROM 10N TO 
17N BETWEEN 77W AND 81W.

THE REST OF THE ATLANTIC OCEAN...

A MIDDLE LEVEL TO UPPER LEVEL TROUGH EXTENDS FROM AN ATLANTIC 
OCEAN 32N45W CYCLONIC CIRCULATION CENTER...TO 28N47W...TO A 
20N61W CYCLONIC CIRCULATION CENTER...TO 13N65W...BEYOND 10N68W 
AT THE VENEZUELA COAST. A COLD FRONT PASSES THROUGH 32N45W TO 
28N46W 23N50W AND 21N55W. A DISSIPATING COLD FRONT CONTINUES 
FROM 21N55W TO 19N65W. CONVECTIVE PRECIPITATION...SCATTERED 
MODERATE TO ISOLATED STRONG FROM 15N TO 23N BETWEEN 55W AND 
65W...FROM THE ATLANTIC OCEAN INTO THE CARIBBEAN SEA. 
RAINSHOWERS ARE POSSIBLE IN THE CARIBBEAN SEA FROM 13N TO 20N 
BETWEEN 69W AND 82W. SCATTERED MODERATE TO STRONG FROM 31N TO 
33N BETWEEN 39W AND 41W. BROKEN TO OVERCAST MULTILAYERED CLOUDS 
AND OTHER POSSIBLE CONVECTIVE PRECIPITATION ARE WITHIN 28N40W 
21N56W. 

A NORTHEASTERN ATLANTIC OCEAN 998 MB LOW PRESSURE CENTER IS NEAR 
34N27W. SURFACE CYCLONIC WIND FLOW COVERS THE ATLANTIC OCEAN TO 
THE NORTH OF 25N BETWEEN THE CANARY ISLANDS AND 35W. GALE-FORCE 
WINDS ARE BEING OBSERVED AROUND THE LOW PRESSURE CENTER TO THE 
NORTHEAST. STRONG UPPER LEVEL WINDS AND COOLER WATERS SHOULD 
LIMIT SUBTROPICAL DEVELOPMENT AS THE LOW WEAKENS AND MOVES 
SLOWLY NORTHWARD DURING THE NEXT DAY OR SO. THIS SYSTEM HAS A 
LOW CHANCE OF BECOMING A SUBTROPICAL OR TROPICAL CYCLONE DURING 
THE NEXT 48 HOURS. ADDITIONAL INFORMATION ON THIS SYSTEM CAN BE 
FOUND IN HIGH SEAS FORECASTS ISSUED BY METEO FRANCE. A MIDDLE 
LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 34N26W. 
A TROUGH EXTENDS FROM THE CENTER TO 30N18W 24N18W 18N20W. 
CONVECTIVE PRECIPITATION...SCATTERED STRONG FROM 33N TO 36WN 
BETWEEN 24W AND 27W. SCATTERED MODERATE TO ISOLATED STRONG FROM 
28N TO 32N BETWEEN 19W AND 21W. 

A 1027 MB HIGH PRESSURE CENTER IS NEAR 34N62W. A SURFACE RIDGE 
EXTENDS FROM THE 1027 MB HIGH CENTER...ACROSS BERMUDA...THROUGH 
29N74W...TO FLORIDA NEAR 28N82W...INTO THE GULF OF MEXICO NEAR 
25N92W.

A 1016 MB HIGH PRESSURE CENTER IS NEAR 23N37W.

PLEASE READ THE HIGH SEAS FORECAST...MIAHSFAT2/FZNT02 KNHC...FOR 
MORE DETAILS ABOUT NORTHEAST TO EAST WINDS 20 TO 25 KNOTS AND 
SEA HEIGHTS TO 9 FEET TO THE SOUTH OF 23N BETWEEN 70W AND 
75W...INCLUDING IN THE WINDWARD PASSAGE. A SECOND AREA OF 
INTEREST CONSISTS OF WINDS 20 KNOTS OR LESS AND SEA HEIGHTS TO 8 
FEET FROM 10N TO 15N TO THE EAST OF 40W.


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

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MT