000 AXNT20 KNHC 101755 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IN THE E ATLANTIC EXTENDS FROM 9N33W TO 19N32W MOVING W AT 10-15 KT. A SW-NE ELONGATED 1009 MB SURFACE LOW IS CENTERED ALONG THE WAVE AXIS NEAR 13N32W. MOST CONVECTION IS OCCURRING ALONG THE SW-NE ORIENTED LOW PRESSURE AXIS WITH SCATTERED TO MODERATE CONVECTION FROM 11N-18N BETWEEN 30W-37W. A TROPICAL WAVE IN THE CENTRAL ATLANTIC EXTENDS FROM 10N54W TO 21N53W MOVING W AT 10-15 KT. THIS WAVE IS WELL DEFINED IN VISIBLE SATELLITE IMAGERY. SSMI TPW IMAGERY SHOWS THE HIGHEST MOISTURE CONFINED TO THE NORTHERN PORTION OF THE WAVE. INTERACTION OF THE WAVE...THE MOIST AIRMASS...AND INTERACTION WITH AN UPPER LOW TO THE NW OF THE WAVE IS HELPING PRODUCE SCATTERED MODERATE CONVECTION JUST NORTH OF THE WAVE AXIS FROM 21N-24N BETWEEN 51W-54W. A TROPICAL WAVE EXTENDS FROM CENTRAL GULF NEAR 24N89W...ACROSS MEXICO AND PORTIONS OF CENTRAL AMERICA...TO THE E PACIFIC NEAR 11N91W. NO DEEP CONVECTION IS NOTED ALONG THE PORTIONS OF THE WAVE IN THE GULF...OVER MEXICO...AND CENTRAL AMERICA. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 12N16W TO 14N30W TO 07N49W. THE ITCZ AXIS EXTENDS FROM 07N49W TO 07N58W. OTHER THAN CONVECTION MENTIONED IN THE TROPICAL WAVES SECTION ABOVE...SCATTERED MODERATE CONVECTION IS FROM 6N-14N BETWEEN 14W-27W. ISOLATED MODERATE CONVECTION IS FROM 7N-10N BETWEEN 39W-41W. ...DISCUSSION... GULF OF MEXICO... UPPER LEVEL CONFLUENCE BETWEEN UPPER LEVEL ANTICYCLONE CENTER OVER TX/MEXICO AND SMALL UPPER LOW IN THE BAY OF CAMPECHE IS HELPING TO INHIBIT CONVECTION ACROSS THE WESTERN HALF OF THE GULF TODAY. THIS INCLUDES THE SOUTHWESTERN GULF...WHERE A TROPICAL WAVE MENTIONED IN THE TROPICAL WAVES SECTION LACKS CONVECTION. AN AREA OF UPPER LEVEL DIFFLUENCE IS ACROSS THE E GULF BETWEEN THE AFOREMENTIONED UPPER LEVEL ANTICYCLONE TO THE WEST...AND AN UPPER TROUGH TO THE E OF FLORIDA. THIS DIFFLUENCE IS COMBINING WITH DEEP LAYER MOISTURE TO HELP PRODUCE SCATTERED THUNDERSTORMS FROM THE YUCATAN CHANNEL N TO 28N...E OF 87W. THIS REGION OF DIFFLUENCE AND COINCIDING SCATTERED THUNDERSTORMS ARE FORECAST TO SHIFT GRADUALLY INTO THE CENTRAL GULF OVER THE NEXT 48 HOURS. AN EASTWARD MOVING SURFACE TROUGH OVER THE BAHAMAS MAY BRING ADDITIONAL SHOWERS AND THUNDERSTORMS TO THE EASTERN GULF THURSDAY AND FRIDAY. CARIBBEAN SEA... UPPER LEVEL WESTERLY FLOW DOMINATES THE CENTRAL AND EASTERN CARIBBEAN. THIS IS OVERRIDING LOW LEVEL EASTERLIES TO PRODUCE A LARGE AREA OF MODERATE DEEP LAYER SHEAR IN THE PRESENCE OF RELATIVELY DRY AIR. THESE FACTORS ARE HELPING TO KEEP THE ENTIRE CENTRAL AND EASTERN CARIBBEAN CONVECTION FREE. THESE FAIR CONDITIONS ARE EXPECTED TO PERSIST FOR THE NEXT DAY OR TWO. A BROAD AREA OF UPPER LEVEL DIFFLUENCE IS OCCURRING OVER THE W CARIBBEAN...BETWEEN A WEAKENING UPPER LOW OVER CUBA NEAR 21N75W...AND ANOTHER SMALL UPPER LOW OVER THE BAY OF CAMPECHE. THIS DIFFLUENCE IS OCCURRING IN THE PRESENCE OF DEEP LAYER MOISTURE TO PRODUCE SCATTERED MODERATE TO ISOLATED STRONG CONVECTION FROM THE N COAST OF PANAMA TO 22N BETWEEN 80W AND 88W. THIS REGION OF DIFFLUENCE WILL SLOWLY WEAKEN OVER THE NEXT TWO DAYS WHILE DRIER AIR TRIES TO MAKE ITS WAY WEST INTO THE AREA. THIS SHOULD BRING ABOUT A GRADUAL DECREASE IN CONVECTION OVER THE W CARIBBEAN OVER THE NEXT 48 HOURS. ...HISPANIOLA... CYCLONIC UPPER LEVEL FLOW IS SPREADING ACROSS THE AREA FROM A LARGE UPPER LOW IN THE ATLANTIC NEAR 26N59W. HISPANIOLA IS FAR ENOUGH REMOVED FROM THE UPPER LOW THAT CONVECTION FROM THE UPPER LOW IS NOT AFFECTING THE AREA. THE UPPER LOW IS EXPECTED TO MOVE SOUTHWEST...NEARER TO HISPANIOLA OVER THE NEXT 48 HOURS. THIS COULD BRING AN INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY TO THE AREA BY FRIDAY. ATLANTIC OCEAN... A LARGE UPPER LOW IS CENTERED NEAR 26N59W DRIFTING SOUTHWESTWARD. SCATTERED MODERATE CONVECTION IS OCCURRING WITHIN 300NM OF THE LOW FROM 24N-31N BETWEEN 55W-64W. A SURFACE TROUGH OVER THE CENTRAL BAHAMAS IS NEAR 24N77W TO 29N74W. THERE ARE INDICATIONS IN VISIBLE SATELLITE IMAGERY THAT A CLOSED LOW MAY BE DEVELOPING IN THE AREA. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE OCCURRING FROM 25N-29N BETWEEN 72W-77W. THIS TROUGH IS EXPECTED TO DRIFT WEST TO NORTHWEST OVER THE NEXT 24 HOURS WITH ONGOING SHOWERS AND THUNDERSTORMS EXPECTED TO CONTINUE WITH THE TROUGH. OTHER DEEP CONVECTION IN THE ATLANTIC IS ASSOCIATED WITH TROPICAL WAVES MENTIONED IN THE TROPICAL WAVES SECTION. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO