000 AXNT20 KNHC 161057 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON MAY 16 2011 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 1015 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ANALYZED FROM 02N48W TO 10N44W MOVING W AT 10-15 KT. TOTAL PRECIPITABLE WATER IMAGERY DEPICTS A NORTHWARD BULGE OF LOW-LEVEL MOISTURE IN THE VICINITY OF THE WAVE AXIS. GLOBAL MODEL GUIDANCE IN THE LOW TO MIDDLE LEVELS ALSO INDICATES WEAK TROUGHING BETWEEN 40W-50W. ISOLATED MODERATE CONVECTION IS FROM 03N-08N BETWEEN 40W-51W. ...ITCZ... ITCZ AXIS IS ALONG 07N11W 04N23W TO A SURFACE TROUGH FROM 02N-07N ALONG 24W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 120 NM EITHER SIDE OF THE AXIS BETWEEN 12W-19W...AND FROM THE EQUATOR TO 05N BETWEEN 21W-28W. THE ITCZ AXIS RESUMES NEAR THE EQUATOR AND 41W THEN INTERSECTS THE TROPICAL WAVE NEAR 02N47W. SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 03N BETWEEN 42W-45W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY INDICATES MOSTLY DRY NW FLOW IS LOCATED ALOFT OVER THE GULF BASIN AS AN UPPER LEVEL TROUGH SHIFTS EASTWARD INTO THE SW NORTH ATLC THIS MORNING. AS OF 16/0900 UTC...THE SOUTHERN EXTENT OF THE WEAKENING COLD FRONT WAS ANALYZED ACROSS THE EASTERN STRAITS OF FLORIDA TO THE YUCATAN CHANNEL. WEST OF THIS FRONT ACROSS THE ENTIRE GULF...A SURFACE RIDGE IS BUILDING IN OVER WESTERN PORTIONS AND IS ANCHORED BY A 1016 MB HIGH CENTERED NEAR 27N97W. WHILE NORTHERLY WINDS IN THE RANGE OF 10 TO 15 KT ARE EXPECTED THROUGH THE MORNING HOURS E OF 92W...LIGHT WINDS OVER THE NW GULF AND AREAS ALONG THE MEXICO GULF COAST W OF 95W WILL CONTINUE TO EXPERIENCE LOW-LEVEL STRATUS AND POSSIBLE AREAS OF LOWERED VISIBILITY THROUGH THE LATE MORNING HOURS. CARIBBEAN SEA... WITH BROAD UPPER LEVEL TROUGHING LOCATED OVER THE SW NORTH ATLC WATERS...GENERALLY DRY W-NW FLOW ALOFT IS NOTED ON WATER VAPOR IMAGERY THIS MORNING. THIS IS PROVIDING FOR OVERALL FAIR CONDITIONS AND CLEAR SKIES OVER MUCH OF THE WESTERN CARIBBEAN W OF 74W. AS NOTED IN THE GULF OF MEXICO...A WEAKENING COLD FRONT EXTENDS ACROSS THE YUCATAN CHANNEL. MOST OF THE UPPER LEVEL DYNAMICS SUPPORTING THE COLD FRONT REMAIN N OF 25N IN THE W ATLC...WHILE ONLY A SUBTLE WIND SHIFT AND LACK OF SIGNIFICANT CONVECTION ARE ASSOCIATED WITH THE COLD FRONT. OVER THE EASTERN CARIBBEAN...MOSTLY SOUTHWESTERLY FLOW ALOFT IS NOTED EAST OF THE UPPER LEVEL TROUGH AXIS AND THIS SUPPORTS A SURFACE TROUGH THAT IS ANALYZED FROM WESTERN HISPANIOLA NEAR 20N74W TO NW VENEZUELA NEAR 12N70W. TOTAL PRECIPITABLE WATER IMAGERY INDICATES AN ABUNDANT AMOUNT OF LOW TO MIDDLE LEVEL MOISTURE IS IN PLACE EAST OF THE SURFACE TROUGH SUSTAINING NUMEROUS SHOWERS CURRENTLY LOCATED E OF 70W. THE OVERALL DIFFLUENT PATTERN IS EXPECTED TO PERSIST OVER THE EASTERN CARIBBEAN THROUGH LATE TUESDAY WITH THE SURFACE TROUGHING FORECAST TO REMAIN NEARLY STATIONARY OVER THE CENTRAL CARIBBEAN AS WELL OVER THE NEXT COUPLE OF DAYS. ATLANTIC OCEAN... AN UPPER LEVEL LOW IS LOCATED OVER THE GREAT LAKES REGION THIS MORNING AND EXTENDS AN UPPER LEVEL TROUGH AXIS THROUGH 32N80W TO THE SE BAHAMAS NEAR 22N73W. THIS UPPER LEVEL TROUGH SUPPORTS A COLD FRONT ANALYZED INTO THE DISCUSSION AREA NEAR 32N77W THAT EXTENDS SW TO WESTERN CUBA NEAR 23N82W. INFRARED SATELLITE IMAGERY AND LIGHTNING DATA SHOW WIDELY SCATTERED SHOWERS AND TSTMS OCCURRING WITHIN 150 NM EAST OF THE FRONT N OF 23N. FARTHER EAST...ANOTHER UPPER LEVEL LOW IS CENTERED NEAR 36N47W AND SUPPORTS A SURFACE TROUGH THAT ENTERS THE DISCUSSION AREA NEAR 32N44W EXTENDING SW TO 21N51W. ANOTHER SURFACE TROUGH IS ANALYZED FROM 26N49W TO 22N66W. A LARGE PORTION OF THESE SURFACE TROUGHS ARE LOCATED EAST OF THE BROAD UPPER LEVEL TROUGH OVER THE BAHAMAS AND ALONG WITH LOW-LEVEL CONVERGENCE IN THE VICINITY OF THE BOUNDARIES THEY CONTINUE TO GENERATE A RATHER LARGE AREA OF SCATTERED SHOWERS AND ISOLATED TSTMS WITHIN 360 NM EITHER SIDE OF A LINE FROM 32N40W TO 18N63W. THE REMAINDER OF THE EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1034 MB HIGH CENTERED NW OF THE IBERIAN PENINSULA NEAR 46N22W. THE SURFACE RIDGE AXIS EXTENDS FROM THE AZORES NEAR 39N30W TO 18N40W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN