000 AXNT20 KNHC 232350 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST TUE NOV 23 2010 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 08N13W 06N32W 04N51W. WIDELY SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 10N BETWEEN 20W-37W. A SURFACE TROUGH IS ANALYZED FROM 06N59W TO 14N55W AND REMAINS EMBEDDED WITHIN BROAD LOW-LEVEL CYCLONIC FLOW OVER THE WESTERN TROPICAL ATLC. SCATTERED MODERATE CONVECTION IS FROM 08N-14N BETWEEN 52W-62W...INCLUDING PORTIONS OF TRINIDAD AND TOBAGO. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL ANTICYCLONIC CIRCULATION COVERS MUCH OF THE GULF WITH PRIMARILY W-SW FLOW ALOFT OCCURRING N OF 20N. THE RIDGE AXIS EXTENDS FROM THE NORTHERN YUCATAN PENINSULA NE OVER THE SOUTHERN FLORIDA PENINSULA TO BEYOND 32N70W. WATER VAPOR INDICATES THIS AIRMASS REMAINS FAIRLY DRY AND SUBSIDENT PROMOTING STABLE CONDITIONS OVER MUCH OF THE REGION THIS EVENING. AT THE SURFACE...A RIDGE AXIS EXTENDS FROM THE SW NORTH ATLC TO EAST-CENTRAL MEXICO NEAR 23N98W PROVIDING GENERALLY 15-20 KT EAST TO SOUTHEAST WINDS OVER THE BASIN EXCEPT OVER THE NE PORTION WHERE WINDS REMAIN CLOSER TO THE ELONGATED SURFACE HIGH CENTER ALONG 30N BETWEEN 60W-85W. A FEW ISOLATED SHOWERS ARE OCCURRING OVER THE SE GULF AND FLORIDA STRAITS S OF 25N E OF 87W. OTHERWISE...LATER IN THE WEEK...AN UPPER LEVEL TROUGH CURRENTLY OVER THE WESTERN U.S. IS FORECAST TO PROGRESS EASTWARD ACROSS THE CENTRAL CONUS AND INTRODUCE THE NEXT COLD FRONT INTO NW GULF LATE THURSDAY BRINGING A ROUND OF STRONG NORTHERLY WINDS OVER THE WESTERN GULF. CARIBBEAN SEA... AN UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED OVER CENTRAL AMERICA NEAR 13N86W AND EXPANDS NORTHWARD INFLUENCING MUCH OF THE GULF OF MEXICO. THE NW CARIBBEAN REMAINS LOCATED ON THE EASTERN PERIPHERY OF THIS UPPER LEVEL FEATURE AND DRY NORTHERLY FLOW DOMINATES N OF 14N W OF 75W. THIS AREA FALLS WEST OF A STRETCHED UPPER LEVEL TROUGH AXIS EXTENDING ALONG 20N FROM 60W TO HISPANIOLA THEN SW TO 16N75W. MOSTLY DRY AIR ACCOMPANIES THE UPPER LEVEL TROUGH AND THEREFORE SIGNIFICANT DEEP CONVECTION IS CONFINED TO THE SW CARIBBEAN AND PORTIONS OF SOUTHERN CENTRAL AMERICA S OF 12N BETWEEN 77W-87W. STRONG NORTHEASTERLY TRADES CONTINUE OVER THE REMAINDER OF THE CARIBBEAN...WHICH LOCATE ON THE SOUTHERN PERIPHERY OF A SURFACE RIDGE ANCHORED BY A 1022 MB HIGH CENTERED OVER THE W ATLC NEAR 31N70W. LOW-LEVEL MOISTURE AND ISOLATED SHOWER ACTIVITY CONTINUES OVER EASTERN PORTIONS OF HISPANIOLA AND THE EASTERN CARIBBEAN E OF 72W THIS EVENING. ATLANTIC OCEAN... AN UPPER LEVEL RIDGE EXTENDS FROM THE GULF OF MEXICO EASTWARD ACROSS THE FLORIDA PENINSULA AND INTO THE SW NORTH ATLC WITH INFLUENCE TO 60W. FARTHER EAST...UPPER LEVEL TROUGHING IS NOTED ON WATER VAPOR IMAGERY N OF 20N BETWEEN 35W-60W. THE UPPER LEVEL RIDGE SUPPORTS A BROAD 1022 MB SURFACE HIGH CENTERED NEAR 31N70W THAT IS PROVIDING MUCH OF THE W ATLC WITH NE TO E WINDS THIS EVENING. HOWEVER...FARTHER EAST AS THE UPPER LEVEL TROUGHING IS MORE PRONOUNCED...THE TAIL END OF A COLD FRONT EXTENDS TO NEAR 31N36W. ISOLATED SHOWERS ARE OCCURRING FROM 29N-33N BETWEEN 34W-45W. THIS LEADS FARTHER EAST WHERE A WEAKNESS WITHIN THE SUBTROPICAL RIDGE IS LOCATED BETWEEN 23W-40W. WITHIN THIS AREA N OF 20N...A 1006 MB LOW IS CENTERED NEAR 27N33W WITH A STATIONARY FRONT SW TO 21N40W AND NE TO BEYOND 32N25W. LOW-LEVEL CONVERGENCE NEAR THIS FRONTAL BOUNDARY IS GENERATING SCATTERED SHOWERS FROM 23N-33N BETWEEN 23W-36W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN