000 AXNT20 KNHC 080006 RRA TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST THU NOV 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...SPECIAL FEATURES... A GALE WARNING CONTINUES IN EFFECT FOR THE SW GULF OF MEXICO AT 07/2100 UTC. THIS GALE IS ASSOCIATED WITH THE COLD FRONT CURRENTLY ANALYZED ACROSS THE NORTH-CENTRAL AND WESTERN GULF. SEE THE HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 10N14W TO 09N20W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 09N20W TO 06N34W TO 08N41W. A SURFACE TROUGH IS ANALYZED AT THE WESTERN EXTENT OF THE AXIS FROM 09N43W TO 06N43W. SCATTERED MODERATE CONVECTION IS FROM 01N-11N BETWEEN 27W-45W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY INDICATES A BROAD LONGWAVE TROUGH OVER THE GREAT LAKES WITH A TROUGH AXIS EXTENDING S-SW TO A BASE OVER THE EASTERN GULF WATERS. THIS MIDDLE TO UPPER LEVEL TROUGH SUPPORTS A COLD FRONT ANALYZED FROM APALACHEE BAY NEAR 29N83W SW TO VERA CRUZ MEXICO NEAR 19N95W. COLD AND DRY AIR SUPPORTS FAIR WEATHER EAST OF THE FRONTAL BOUNDARY N OF 24N. A SHORT-WAVE UPPER-LEVEL TROUGH IN THE SW GULF IS SUPPORTING LOW-LEVEL CONVERGENCE...THUS SCATTERED SHOWERS/ISOLATED TSTMS S OF 24N E OF 93W. THE MOST IMPORTANT IMPACT ASSOCIATED WITH THE FRONT IS A GALE WARNING ACROSS A PORTION OF THE WESTERN GULF WATERS WHICH IS FORECAST TO BE VALID THROUGH EARLY FRIDAY. SEE SPECIAL FEATURES ABOVE. A MIDDLE-LEVEL COL OR REGION OF LOW PRESSURE EXTENDS FROM THE FAR NW CARIBBEAN TO JUST NORTH OF THE YUCATAN CHANNEL. DIVERGENT WINDS RESULTING FROM THIS COL ARE SUPPORTING SCATTERED SHOWERS IN THE SE GULF S OF 24N BETWEEN 84W-88W. BY EARLY FRIDAY...WITH FRONTAL PASSAGE HAVING OCCURRING OVER MUCH OF THE GULF...NORTHEAST WINDS WILL DOMINATE GENERALLY IN THE RANGE OF 20 TO 30 KT AND GRADUALLY DECREASE THROUGH THE DURATION OF THE UPCOMING WEEKEND. CARIBBEAN SEA... AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED S OF WESTERN CUBA NEAR 21N80W...WHICH IS PROVIDING DIVERGENT WIND FLOW ALOFT FOR THE NW CARIBBEAN AND PORTIONS OF NORTHERN CENTRAL AMERICA. AT THE SURFACE AND SW OF THE UPPER-LEVEL RIDGE CENTER...A 1009 MB LOW PRESSURE CENTER IS NEAR 19N85W WITH A TROUGH AXIS EXTENDING FROM 21N86W TO 17N85W. SCATTERED MODERATE CONVECTION AND TSTMS ARE OCCURRING W OF 83W. AN ASCAT PASS SHOWS A SURFACE TROUGH AXIS EXTENDING FROM 16N80W SE TO 09N76W...WHICH IS SUPPORTING A LINE OF SCATTERED SHOWERS S OF 16N BETWEEN 77W-82W. THE REMAINDER OF THE CENTRAL AND EASTERN CARIBBEAN IS UNDER THE INFLUENCE OF RELATIVELY DRIER NORTH-NORTHEASTERLY FLOW ALOFT ON THE EASTERN PERIPHERY OF THE UPPER LEVEL ANTICYCLONE. THE OVERALL STABILITY IS RESULTING IN MOSTLY FAIR CONDITIONS AND MOSTLY CLEAR SKIES E OF 77W. TRADES ARE EXPECTED TO PERSIST GENERALLY IN THE RANGE OF 10 TO 20 KT THROUGH LATE SATURDAY WHEN THE PRESSURE GRADIENT ACROSS THE BASIN WILL BEGIN TO GRADUALLY STRENGTHEN DUE TO STRONG HIGH PRESSURE BUILDING TO THE NORTH ACROSS THE SW NORTH ATLC. HISPANIOLA... DRY NE WINDS ALOFT AND STRONG SUBSIDENCE CONTINUE TO SUPPORT FAIR WEATHER ACROSS THE ISLAND. CLOUDINESS AND ISOLATED SHOWERS/TSTMS ARE MINIMUM IN THE CENTRAL-SOUTHERN ISLAND...THESE LIKELY ASSOCIATED WITH OROGRAPHIC LIFTING. EXCEPT FOR AFTERNOON/EARLY EVENING SHOWERS...FAIR WEATHER CAN BE EXPECTED THROUGHOUT SATURDAY NIGHT. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL RIDGE DOMINATE THE WESTERN ATLC. A WEAKNESS WITHIN THE RIDGE ALOFT REFLECTS TO THE SURFACE AS A SURFACE TROUGH ANALYZED FROM THE NORTHERN BAHAMAS NEAR 26N77W TO 31N77W AND INTO A 1011 MB LOW CENTERED ALONG THE NORTH CAROLINA COAST NEAR 36N74W. ISOLATED SHOWERS ARE WITHIN 220 NM EAST OF THE AXIS. FARTHER EAST...A MIDDLE TO UPPER LEVEL TROUGH SUPPORTS A 1014 MB LOW CENTERED NEAR 31N46W AND ASSOCIATED WARM FRONT EXTENDING E-NE TO BEYOND 32N46W. A STATIONARY FRONT EXTENDS SW FROM THE LOW CENTER TO 28N52W AND BECOMES A SHEAR LINE TO 27N59W. MIDDLE TO UPPER LEVEL DIFFLUENCE IS OCCURRING EAST OF THE TROUGH AXIS AND INDUCES TROUGHING AS THE SURFACE EXTENDING TO THE SW OF THE LOW CENTER. SCATTERED SHOWERS ARE N OF 19N BETWEEN 40W-54W. OTHERWISE...THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1030 MB HIGH CENTERED N OF THE DISCUSSION AREA. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR