000 AXNT20 KNHC 142325 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT FRI JUN 14 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2245 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IMPACTING THE CARIBBEAN EXTENDS FROM 21N67W TO 10N69W MOVING W AT 15 KT. THE WAVE LIES WITHIN A SURGE OF DEEP LAYER MOISTURE PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/STRONG CONVECTION IS FROM 15N-17N BETWEEN 67W- 71W. SIMILAR ACTIVITY IS ACROSS HISPANIOLA FROM 19N-20N BETWEEN 68W-73W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE COAST OF GUINEA-BISSAU NEAR 12N16W TO 7N23W. THE ITCZ BEGINS NEAR 7N23W AND CONTINUES ALONG 6N38W 5N52W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 7N-10N BETWEEN 16W-19W. SIMILAR ACTIVITY IS FROM 4N-8N BETWEEN 31W-46W. ...DISCUSSION... THE GULF OF MEXICO... WEAK SURFACE RIDGING DOMINATES THE GULF OF MEXICO AROUND A 1016 MB HIGH NEAR 25N90W. THE RIDGE IS SUPPORTED BY AN UPPER LEVEL RIDGE COVERING THE WESTERN GULF CENTERED OVER CENTRAL MEXICO NEAR 19N102W. LIGHT ANTI-CYCLONIC WINDS ARE AROUND THE HIGH CENTER INCREASING TO 10 KT OVER THE WESTERN GULF. AN UPPER LEVEL TROUGH COVERS THE REMAINDER OF THE GULF WITH AXIS JUST EAST OF FLORIDA CONTINUING INTO THE NW CARIBBEAN. THE UPPER TROUGH SUPPORTS A COLD FRONT THAT IS PUSHING INTO THE FLORIDA PANHANDLE AND NE GULF ALONG 30N81W 29N88W 30N90W...AS OF 2100 UTC. A CLUSTER OF SHOWERS/THUNDERSTORMS IS ALONG THE FRONT OVER NE FLORIDA...AS WELL AS OVER SE LOUISIANA. A LARGE CLUSTER OF SHOWERS/THUNDERSTORMS IS ALSO OVER SE FLORIDA. THE CENTRAL GULF REMAINS QUITE CLEAR AS DRY AIR ALOFT SINKS AROUND THE WEST SIDE OF THE UPPER TROUGH. THE FRONT IS EXPECTED TO MOVE SLIGHTLY SOUTH...BUT MAINLY EAST OVER THE NEXT 24 HOURS. WEAK SURFACE RIDGING WILL REMAIN THE DOMINANT FEATURE THROUGHOUT THE WEEKEND. THE CARIBBEAN SEA... AN UPPER LEVEL TROUGH SINKS INTO THE NW CARIBBEAN FROM CENTRAL CUBA TO HONDURAS DRAWING DRY AIR OVER THIS PORTION OF THE BASIN. MOIST AIR IS WRAPPING AROUND THE WEST SIDE OF THE UPPER LOW AND CONTINUING AROUND AN UPPER LEVEL RIDGE COVERING THE REMAINDER OF THE BASIN CENTERED EAST OF THE WINDWARD ISLANDS. THE MOIST AIR ALOFT IS SUPPORTING A FEW UPPER LEVEL CLOUDS. DAYTIME HEATING AND INSTABILITY ALONG WITH DIFFLUENCE ALOFT ARE PRODUCING SCATTERED SHOWERS/THUNDERSTORMS OVER CENTRAL AND EASTERN CUBA. WIDESPREAD SHOWERS/THUNDERSTORMS ARE ALSO OVER THE FAR SW CARIBBEAN SOUTH OF 11N AND ACROSS NICARAGUA...COSTA RICA...AND PANAMA ASSOCIATED WITH THE MONSOON TROUGH THAT EXTENDS THROUGH PANAMA TO NORTHERN COLOMBIA. A TROPICAL WAVE NEAR 69W IS IMPACTING THE CENTRAL CARIBBEAN SUPPORTING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 14N-18N BETWEEN 67W-75W. HEAVY SHOWERS AND THUNDERSTORMS ARE ALSO OVER THE NORTHERN HALF OF HISPANIOLA. SEE TROPICAL WAVE SECTION FOR MORE DETAILS. SCATTERED SHOWERS ARE ALSO MOVING THROUGH THE WINDWARD ISLANDS AND SE CARIBBEAN. TRADEWIND FLOW OF MAINLY 20 KT IS PRESENT THROUGHOUT THE CENTRAL AND EASTERN CARIBBEAN WITH 25 KT WINDS NOTED NEAR THE COAST OF COLOMBIA. THE WAVE IS EXPECTED TO CONTINUE MOVING WEST IMPACTING THE CENTRAL AND THEN WESTERN CARIBBEAN. HISPANIOLA... A CLUSTER OF HEAVY SHOWERS/THUNDERSTORMS IS CURRENTLY OVER NORTHERN HISPANIOLA FROM 19N-20N BETWEEN 69W-73W. THIS ACTIVITY IS MOSTLY TIED TO DAYTIME HEATING AND INSTABILITY PRESENT ON MOST AFTERNOONS. MOIST AIR ALOFT IS ALSO FLOWING OVER THE ISLAND BETWEEN AN UPPER TROUGH TO THE WEST AND AN UPPER RIDGE TO THE EASTER. A TROPICAL WAVE IS ALSO APPROACHING THE ISLAND FROM THE EAST. TOTAL PRECIPITABLE WATER IMAGERY INDICATES THAT THE INCREASED MOISTURE OF THE WAVE IS BEGINNING TO MOVE OVER THE EASTERN HALF OF THE ISLAND. THIS AREA OF MOISTURE WILL CONTINUE TO MOVE WEST OVER HAITI. INCREASED MOISTURE COULD MEAN AN INCREASE IN RAINFALL OVER THE NEXT 24-48 HOURS. THE UPPER TROUGH TO THE WEST IS ALSO EXPECTED TO DRIFT EAST...WHICH MAY FURTHER SUPPORT CONVECTION ACTIVITY OVER THE ISLAND. THE ATLANTIC OCEAN... ISOLATED SHOWERS/THUNDERSTORMS ARE THROUGHOUT THE WEST ATLC WEST OF 68W ASSOCIATED WITH AN UPPER LEVEL TROUGH EXTENDING FROM 32N76W TO 23N80W. THE UPPER TROUGH ALSO SUPPORTS A COLD FRONT WHICH EXTENDS THROUGH THE AREA ALONG 32N75W TO 30N81W. HEAVY SHOWERS/THUNDERSTORMS ARE UP TO 100 NM SOUTH OF THE AXIS. THE REMAINDER OF THE BASIN IS DOMINATED BY ONE LARGE AND BROAD SURFACE RIDGE ANCHORED BY A 1028 MB HIGH NEAR 31N41W. ALOFT...UPPER RIDGING IS ALONG 65W SUPPORTING THE SURFACE RIDGE. A WEAK UPPER TROUGH EXTENDS FROM 32N59W TO 26N52W. TO THE EAST...AN UPPER LEVEL LOW IS NEAR 26N40W SUPPORTING A FEW UPPER LEVEL CLOUDS. FINALLY...A THIRD UPPER TROUGH EXTENDS OVER NW AFRICA. A NARROW UPPER RIDGE IS BETWEEN THESE TWO EASTWARDMOST TROUGHS ALONG 30W. THE LAST VISIBLE SATELLITE IMAGES OF THE DAY INDICATE A LARGE AREA OF SAHARAN DUST EXTENDS OFF THE COAST OF AFRICA AND CONTINUES TO NEAR 59W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON