000 AXNT20 KNHC 221748 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT JUN 22 2013 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 WWWW UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 12N36W TO 3N36W MOVING W NEAR 15 KT. WAVE IS EMBEDDED WITHIN A LOW AMPLITUDE SURGE OF DEEP MOISTURE AS DEPICTED BY THE TOTAL PRECIPITABLE WATER IMAGERY. DENSE SAHARAN DUST COVERS THE AREA NE OF THIS WAVE TO AFRICA LIMITING SHOWER ACTIVITY TO SCATTERED MODERATE WITH EMBEDDED CLUSTERS OF ISOLATED STRONG CONVECTION FROM 3N-7N BETWEEN 33W-41W. TROPICAL WAVE EXTENDS FROM 11N49W TO 3N50W MOVING W AT 15 KT. WAVE IS EMBEDDED WITHIN A LOW AMPLITUDE SURGE OF DEEP MOISTURE AS DEPICTED BY THE TOTAL PRECIPITABLE WATER IMAGERY. PATCHES OF SAHARAN DUST ARE W OF THIS WAVE TO THE PREVIOUS TROPICAL WAVE AND CONTINUES TO LIMITING SHOWER ACTIVITY. NO ASSOCIATED DEEP CONVECTION. TROPICAL WAVE IN THE W CARIBBEAN EXTENDS FROM 19N82W TO 11N82W MOVING W 10-15 KT. WAVE IS TRAILING A SURGE OF DEEP MOISTURE AS DEPICTED BY THE TOTAL PRECIPITABLE WATER IMAGERY. WAVE REMAINS AT THE BASE OF AN UPPER TROUGH. WAVE IS INTERACTING WITH THE MONSOON TROUGH TO GENERATE SCATTERED SHOWERS/THUNDERSTORMS BETWEEN THE WAVE AXIS AND THE COAST OF NICARAGUA. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 12N16W AND CONTINUES TO 9N21W WHERE THE ITCZ BEGINS AND CONTINUES TO 7N34W. THE ITCZ BECOMES DISRUPTED BY THE TROPICAL WAVE. THE ITCZ RESUMES NEAR 6N38W ALONG 5N43W TO 6N48W WHERE IT IS AGAIN DISRUPTED BY THE SECOND TROPICAL WAVE. THE ITCZ AGAIN RESUMES NEAR 6N52W AND CONTINUES INLAND OVER SOUTH AMERICA NEAR 6N58W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 4N-8N BETWEEN 21W-26W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LOW IS SITUATED OVER N GEORGIA SUPPORTING A STATIONARY FRONT IN THE W ATLC WITH A SURFACE TROUGH CONTINUING ACROSS NE FLORIDA INTO THE GULF AT 22/1500 UTC NEAR 30N83W ALONG 28N88W TO 29N92W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 125 NM S OF THE TROUGH E OF 90W. ISOLATED SHOWERS/THUNDERSTORMS ARE N OF 29N FROM ALABAMA TO E OF GALVESTON TEXAS. ISOLATED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE OVER THE W BAY OF CAMPECHE S OF 21N W OF 94W. THE REMAINDER OF THE GULF IS UNDER THE INFLUENCE OF WEAK SURFACE RIDGE WITH A 1019 MB HIGH LOCATED JUST S OF TAMPICO MEXICO AND ACCOMPANYING CLEAR SKIES. SURFACE RIDGE WILL PREVAIL ACROSS THE GULF THROUGH WED. CARIBBEAN SEA... AN UPPER TROUGH EXTENDS FROM THE W ATLC THROUGH AN UPPER LOW N OF E CUBA COVERING THE CARIBBEAN BETWEEN 72W-83W. THE NW FLOW ALOFT COUPLED WITH THE SE SURFACE FLOW ARE GENERATING ISOLATED SHOWERS/THUNDERSTORMS MAINLY N OF 18N BETWEEN 81W-87W. THE MONSOON TROUGH EXTENDS ACROSS THE SW CARIBBEAN FROM COLOMBIA NEAR 9N76W ALONG 10N79W TO ACROSS COSTA RICA NEAR 9N84W AND IS GENERATING SCATTERED SHOWERS/THUNDERSTORMS S OF 11N BETWEEN 79W- 83W. A BROAD UPPER RIDGE ANCHORED IN THE TROPICAL ATLC IS GIVING THE E CARIBBEAN MOSTLY S TO SW FLOW ALOFT WHICH IS ADVECTING MOISTURE ALOFT OVER THE E CARIBBEAN AND COUPLED WITH THE EASTERLY TRADE WINDS ARE GENERATING SCATTERED LOW LEVEL SHOWERS WITH POSSIBLE ISOLATED THUNDERSTORMS N OF 13N W OF 71W TO ACROSS THE LESSER ANTILLES. THE TROPICAL WAVE IN THE W CARIBBEAN WILL MOVE INTO CENTRAL AMERICA THIS AFTERNOON THROUGH TONIGHT. A WEAK TROPICAL WAVE WILL MOVE INTO E CARIBBEAN EARLY MON AND REACH THE CENTRAL CARIBBEAN TUE. A THIRD TROPICAL WAVE WILL MOVE INTO THE E CARIBBEAN WED. HISPANIOLA... THE BROAD UPPER RIDGE OVER THE E CARIBBEAN/TROPICAL ATLC IS DRAWING MOISTURE ALOFT OVER THE DOMINICAN REPUBLIC AND IS GENERATING ISOLATED SHOWERS E OF 71W. THE GLOBAL MODELS SHOW THE UPPER LOW N OF E CUBA WILL REMAIN NEAR STATIONARY THROUGH EARLY MON BEFORE WEAKENING. THE UPPER RIDGE OVER THE E CARIBBEAN WILL EXTEND W ACROSS THE CARIBBEAN MON THROUGH WED. CHANCES OF SHOWERS WILL INCREASE SLIGHTLY ON MON AND TUE AS A WEAK TROPICAL WAVE MOVES INTO THE E AND CENTRAL CARIBBEAN. MOISTURE INCREASE EVEN MORE ON WED AHEAD OF A STRONG TROPICAL WAVE THAT WILL ENTER THE E CARIBBEAN WED INCREASING SHOWERS BY THROUGH THE END OF THE WEEK. ATLANTIC OCEAN... THE UPPER LOW OVER N GEORGIA IS SUPPORTING A STATIONARY FRONT THAT ENTERS THE REGION AT 22/1500 UTC NEAR 32N79W TO 31N81W WHERE A SURFACE TROUGH CONTINUES ACROSS NE FLORIDA NEAR JACKSONVILLE AND CONTINUES INTO THE GULF OF MEXICO. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 60/75 NM SE OF THE FRONT/TROUGH TO ACROSS FLORIDA. A SURFACE TROUGH EXTENDS AT 22/1500 UTC FROM 30N77W ALONG 27N78W TO 24N79W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS E OF THE WAVE TO 76W. THIS SURFACE TROUGH IS BENEATH AN UPPER RIDGE THAT COVERS THE W ATLC ANCHORED NEAR GRAND BAHAMA ISLAND AND EXTENDING A RIDGE AXIS N TO BEYOND 32N75W. A SMALL LOW KNOWN AS A SCREAMING EAGLE IS MOVING RAPIDLY ACROSS THE ATLC ABOUT 450 NM N-NE OF THE LEEWARD ISLANDS. THIS FEATURE WILL DEPICTED AS A SURFACE TROUGH ON THE 22/1800 UTC SURFACE ANALYSIS. THE REMAINDER OF THE ATLC IS DOMINATED BY A BROAD SURFACE RIDGE ANCHORED BY A 1034 MB HIGH NEAR THE AZORES. A PLUME OF DENSE SAHARAN DUST COVERS THE ATLC N OF 10N E OF 35W. THIS DUST THINS OVER THE ARE FROM 10N-24N BETWEEN 35W-54W. SURFACE RIDGE WILL CONTINUE TO DOMINATE THE ATLC THROUGH WED. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW