000 AXNT20 KNHC 140554 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST SAT NOV 14 2009 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 7N11W 5N16W 6N29W 8N32W 8N38W 7N41W 4N52W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 3N-9N BETWEEN 17W-28W. A SURFACE TROUGH IS ANALYZED ALONG 31W FROM 4N-11N WITH SCATTERED SHOWERS FROM 9N-14N BETWEEN 27W-33W. A SECOND SURFACE TROUGH IS ANALYZED FROM 13N34W TO A 1010 MB LOW NEAR 9N39W AND CONTINUING TO 5N41W. SCATTERED SHOWERS ARE FROM 4N-14N BETWEEN 33W-42W. ...DISCUSSION... GULF OF MEXICO... A SURFACE RIDGE EXTENDS ACROSS THE CENTRAL GULF ALONG 90W ANCHORED ON A 1013 MB HIGH CENTERED OVER EASTERN LOUISIANA NEAR 30N90W. THIS RIDGE IS PROVIDING GENERALLY FAIR WEATHER ACROSS THE GULF WITH LIGHT NLY WINDS E OF 90W AND SLY RETURN FLOW UP TO 15 KT W OF 90W. ALOFT...AN UPPER LEVEL RIDGE EXTENDS FROM 26N95W NE ACROSS MUCH OF THE EASTERN CONUS AND AN UPPER LEVEL LOW IS LOCATED SOUTH OF THIS RIDGE CENTERED OVER EASTERN MEXICO NEAR 21N97W. STRONG SUBSIDENCE IS SUPPORTING A RELATIVELY COOL AND DRY AIRMASS OVER MUCH OF THE GULF AS NOTED IN WATER VAPOR IMAGERY. THE SURFACE RIDGE IS FORECAST TO SLIDE GRADUALLY EASTWARD THROUGH EARLY MONDAY WITH SE RETURN FLOW SPREADING EASTWARD AS WELL AHEAD OF THE NEXT COLD FRONT TO ENTER THE NW GULF WATERS MONDAY AFTERNOON. CARIBBEAN SEA... A STATIONARY FRONT EXTENDS FROM THE W ATLC ACROSS ERN CUBA NEAR 21N77W INTO THE NW CARIBBEAN TO GRAND CAYMAN ISLANDS NEAR 19N82W. A PRE-FRONTAL SURFACE TROUGH SE OF THE FRONT EXTENDS FROM 20N75W ACROSS JAMAICA TO 12N82W. ISOLATED SHOWERS ARE WITHIN 90 NM EITHER SIDE OF THE SURFACE TROUGH. THIS PAIR OF BOUNDARIES ARE SUPPORTED ALOFT BY AN UPPER LEVEL LOW IN THE W ATLC AND ASSOCIATED TROUGH AXIS THAT EXTENDS OVER THE SE BAHAMAS AND CUBA TO THE YUCATAN CHANNEL. FARTHER SOUTH...SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING OVER THE SW CARIBBEAN S OF 12N BETWEEN 77W-84W IN ASSOCIATION WITH LOW-LEVEL SURFACE CONVERGENCE AND UPPER DIFFLUENCE ASSOCIATED WITH A BROAD UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED NEAR 13N80W. UPPER LEVEL RIDGING COVERS THE REMAINDER OF THE CARIBBEAN BASIN WITH MODERATE SUBSIDENCE AND DRY AIR ALOFT. A FEW ISOLATED LOW-LEVEL SHOWERS HOWEVER ARE ACROSS HISPANIOLA AND ADJACENT COASTAL WATERS N OF 17N BETWEEN 69W-76W. ATLANTIC OCEAN... A COMPLEX AREA OF LOW PRESSURE IS LOCATED OFF THE NORTH CAROLINA COAST AND CENTERED AS A 996 MB LOW NEAR 34N74W. A STATIONARY FRONT EXTENDS EAST OF THE SURFACE CIRCULATION AND ENTERS THE DISCUSSION AREA NEAR 32N69W AND CONTINUES ALONG 29N70W TO THE SE BAHAMAS AND THEN TO EASTERN CUBA NEAR 21N77W. A SURFACE TROUGH IS ANALYZED TO THE E ALONG 32N66W TO 24N70W AND ACROSS THE TURKS AND CAICOS ISLANDS TO EASTERN CUBA NEAR 20N75W. SCATTERED SHOWERS AND TSTMS ARE PRIMARILY ASSOCIATED WITH THE SURFACE TROUGH AND ARE OCCURRING WITHIN 200 NM E OF THE BOUNDARY S OF 25N. MORE CONCENTRATED CONVECTION IS FROM 25N-32N BETWEEN 50W-68W. THESE BOUNDARIES ARE SUPPORTED BY AN UPPER LEVEL LOW CENTERED OFF THE NORTH CAROLINA COAST NEAR 34N73W AND ASSOCIATED TROUGHING THAT DIPS SOUTHWARD TO 20N. UPPER LEVEL DIFFLUENCE E OF THE TROUGH AXIS ALONG 70W IS ALSO ENHANCING THE CURRENT CONVECTION. TO THE E OVER THE CENTRAL ATLC...A 1010 MB LOW IS CENTERED NEAR 32N29W WITH A COLD FRONT THAT EXTENDS SW TO 28N40W AND THEN NW TO 31N48W. ISOLATED SHOWERS ARE WITHIN 90 NM E OF THE FRONT. THIS FRONT IS FAIRLY WEAK DUE TO PREDOMINANTLY WESTERLY UPPER LEVEL FLOW N OF 29N E OF 45W. AN UPPER LEVEL TROUGH IS LOCATED SW OF THE UPPER LEVEL WESTERLY FLOW WITH AXIS FROM 24N45W TO SURINAME IN SOUTH AMERICA NEAR 6N56W. UPPER LEVEL DIFFLUENCE E OF THE UPPER TROUGH IS GENERATING POSSIBLE ISOLATED SHOWERS FROM 8N-17N BETWEEN 40W-51W. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A BROAD SURFACE RIDGE ANCHORED BY A 1020 MB HIGH NEAR 25N26W. $$ HUFFMAN