000 AXNT20 KNHC 110004 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED SEP 10 2014 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 2345 UTC. ...SPECIAL FEATURES... A TROPICAL WAVE IN THE E ATLANTIC EXTENDS FROM 20N32W TO 10N34W MOVING W AT 10-15 KT. AN ELONGATED 1009 MB SURFACE LOW IS CENTERED ALONG THE WAVE AXIS NEAR 14N34W. AT THIS MOMENT...SCATTERED MODERATE CONVECTION IS OCCURRING W OF THE WAVE AXIS FROM 13N-18N BETWEEN 33W-37W. THIS SYSTEM IS BECOMING BETTER ORGANIZED THIS EVENING...AND EXPECT IT TO MOVE TOWARD AN AREA MORE FAVORABLE FOR DEVELOPMENT. DUE TO THIS...THE NATIONAL HURRICANE CENTER GAVE THIS SYSTEM A MEDIUM CHANCE FOR DEVELOPMENT IN THE NEXT 48 HOURS. ...TROPICAL WAVES... A TROPICAL WAVE IN THE CENTRAL ATLANTIC EXTENDS FROM 22N54W TO 09N56W MOVING W AT 10-15 KT. THIS WAVE CONTINUES TO SHOW A DEFINED SIGNATURE ON VISIBLE SATELLITE. DESPITE THAT...NO CONVECTION IS RELATED TO THIS WAVE AS A SIGNIFICANT AMOUNT OF DUST AND SAHARAN DRY AIR PREVAILS IN THE ENVIRONMENT OF IT. A TROPICAL WAVE EXTENDS ACROSS THE YUCATAN PENINSULA TO GUATEMALA AND INTO THE PACIFIC WITH AXIS EXTENDING FROM 24N90W TO 11N91W. NUMEROUS SHOWERS AND THUNDERSTORMS ARE RELATED TO THIS WAVE...BUT THIS ACTIVITY IS LOCATED ACROSS CENTRAL AMERICA FROM 14N-21N. THE OFFSHORE PORTIONS OF THIS WAVE ONLY HAVE ISOLATED CONVECTION FROM 22N-24N BETWEEN 87W-90W ACROSS THE GULF WATERS AND FROM 11N-14N ACROSS ON THE PACIFIC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 10N15W TO 14N25W TO 14N34W TO 09N45W. THE ITCZ AXIS EXTENDS FROM 09N45W TO THE COAST OF GUYANA NEAR 07N58W. OTHER THAN CONVECTION MENTIONED IN THE TROPICAL WAVES SECTION ABOVE...SCATTERED MODERATE CONVECTION IS FROM 10N- 15N BETWEEN 26W-29W. ...DISCUSSION... GULF OF MEXICO... ISOLATED SHOWERS AND THUNDERSTORMS ARE ONLY VISIBLE ACROSS THE SE PORTION OF THE BASIN MAINLY DUE TO THE INSTABILITY GENERATED BY THE TROPICAL WAVE ACROSS CENTRAL AMERICA AND THE DIURNAL CONVECTION FROM CUBA AND THE FLORIDA PENINSULA MOVING OFFSHORE. THIS ACTIVITY IS LOCATED E OF 90W...S OF 27N. AT UPPER LEVELS...AN UPPER-LEVEL LOW CENTERED NEAR 20N93W IS COUPLING WITH AN UPPER-LEVEL HIGH WITH CENTER LOCATED ACROSS E TEXAS CREATING CONFLUENCE ACROSS THE WESTERN GULF WHILE OVER THE E...AN AREA OF WEAK UPPER-LEVEL DIFFLUENCE HAS DEVELOPED ENHANCING CONVECTION. SCATTERED CONVECTION IS EXPECTED TO SHIFT TO THE CENTRAL GULF OVER THE NEXT 24-48 HOURS. A WEAK LOW PRESSURE CENTER THAT DEVELOPED OVER THE BAHAMAS MAY BRING ADDITIONAL MOISTURE/CONVECTION TO THE EASTERN GULF BY THE END OF THE WEEK. CARIBBEAN SEA... NUMEROUS SHOWERS AND THUNDERSTORMS CONTINUE ACROSS THE SOUTHERN CARIBBEAN WATERS MAINLY S OF 19N BETWEEN 76W-87W. SSMI TPW IMAGERY SHOWS A HIGH LEVEL OF MOISTURE AVAILABLE ACROSS THIS AREA WHICH IS BEING ENHANCED THE PROXIMITY OF THE MONSOON TROUGH AND BY UPPER LEVEL DIVERGENCE. THE REST OF THE BASIN IS UNDER A STRONG DEEP LAYER WIND SHEAR REGIME AND DRY AIR...THEREFORE FAIR WEATHER IS PREVAILING. THESE CONDITIONS ARE EXPECTED OVER THE NEXT 24-48 HOURS. ...HISPANIOLA... ISOLATED CONVECTION REMAINS OVER HAITI MAINLY CAUSED BY DIURNAL HEATING AND OROGRAPHIC LIFTING. SOME UPPER LEVEL DIFFLUENCE IS ALSO PRESENT ACROSS THE WESTERN HISPANIOLA...WHICH IS ENHANCING THE CONVECTION. THIS DIFFLUENCE IS GENERATED BY THE PROXIMITY OF AN UPPER-LEVEL LOW ACROSS THE ATLANTIC...WITH CENTER NEAR 23N63W. THIS LOW IS EXPECTED TO MOVE W OVER THE NEXT 24-48 HOURS...WHICH COULD ENHANCE SOME CONVECTION ACROSS THE ISLAND. ATLANTIC OCEAN... ASIDE FROM THE ACTIVITY GENERATED NEAR THE WAVE AND LOW PRESSURE DESCRIBED IN THE SPECIAL FEATURES SECTION...SCATTERED MODERATE CONVECTION CONTINUES E OF A SURFACE TROUGH LOCATED FROM 30N63W TO 25N65W. THIS ACTIVITY IS LOCATED E OF 63W BETWEEN 23N-30N. AN UPPER-LEVEL LOW IS RELATED TO THIS ACTIVITY...WHICH CENTER IS LOCATED NEAR 23N63W. A WEAK AREA OF LOW PRESSURE NEAR NORTHERN BAHAMAS IS SHOWING SOME SIGNS OF ORGANIZATION. ALTHOUGH THE ENVIRONMENT IS UNFAVORABLE FOR SIGNIFICANT DEVELOPMENT...SCATTERED CONVECTION IS EXPECTED ACROSS THE BAHAMAS...FLORIDA AND THE ADJACENT WATERS OVER THE NEXT 24-48 HOURS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ RIVERA