000 AXNT20 KNHC 271743 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT FRI JUN 27 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... ATLANTIC TROPICAL WAVE EARLIER ALONG 24W WAS SHIFTED SLIGHTLY WESTWARD AND EXTENDS FROM 13N27W TO 04N30W WAS MOVING WEST AT 20 KT. SCATTERED MODERATE ISOLATED STRONG CONVECTION ASSOCIATED WITH THE WAVE WAS CONFINED TO AN AREA FROM 05N TO 08N BETWEEN 30W AND 35W. ATLANTIC TROPICAL WAVE ALONG 47W FROM 05N TO 15N...MOVING WESTWARD AT 15 KT. SCATTERED MODERATE CONVECTION FROM 09N TO 11N BETWEEN 45W AND 49W. FAR EASTERN CARIBBEAN TROPICAL WAVE ALONG 61W/62W SOUTH OF 17N...MOVING WESTWARD AT 15 TO 20 KT. THE WAVE AXIS HAS CROSSED OVER THE WINDWARD ISLANDS INTO THE FAR E CARIBBEAN SEA. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS OCCURRING OVER BARBADOS...GRENADA AND JUST N OF TRINIDAD. CARIBBEAN TROPICAL WAVE ALONG 81W SOUTH OF 18N WAS DECELERATING AND WAS NOW MOVING WESTWARD AT 10 TO 15 KNOTS. THE WAVE WAS EMBEDDED WITH AN AREA OF SAHARAN AIR AND OTHERWISE GENERALLY STABLE CONDITIONS WITH NO CONVECTION. SCATTERED STRONG CONVECTION S OF 12N BETWEEN 76W AND 84W WAS RELATED TO THE MONSOON TROUGH. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE COAST OF SENEGAL NEAR 12N16W TO 10N20W. ITCZ EXTENDS FROM 10N20W TO 06N35W TO THE COAST OF SOUTH AMERICA NEAR 02N51W. SCATTERED MODERATE CONVECTION WAS NOTED FROM 04N TO 08N BETWEEN 40W AND 45W. ...DISCUSSION... ...THE GULF OF MEXICO... A FAIRLY SHARP UPPER LEVEL TROUGH EXTENDS A CYCLONIC CIRCULATION OVER NW ARKANSAS SOUTHWARD ACROSS THE UPPER TEXAS COAST TO NEAR 24N97W. AN AMPLIFIED RIDGE EXISTS E OF THE TROUGH OVER THE SE CONUS WITH AN EMBEDDED UPPER LEVEL ANTICYCLONE OVER NORTHERN FLORIDA. AT THE SURFACE...RIDGE EXTENDS ALONG THE NORTHERN GULF COAST TO A 1020 MB STATIONARY HIGH NEAR DESTIN FLORIDA. A WEAK SURFACE TROUGH WAS OVER THE BAY OF CAMPECHE FROM 24N93W TO THE NEAR VERACRUZ MEXICO. ACTIVE CONVECTIVE IS OCCURRING OVER THE NORTHWEST GULF WITHIN 60 NM OF 28N93W WITH ADDITIONAL CELLS DEVELOPING JUST INLAND OVER SOUTH-CENTRAL LOUISIANA AND NEAR THE MOUTH OF THE MISSISSIPPI RIVER. E OF THE UPPER TROUGH FROM 25N TO 30N BETWEEN 90W AND 95W. UPPER LEVEL ANTICYCLONIC FLOW COVERS MOST OF CENTRAL PORTION. RELATIVELY WEAK AT THIS TIME. ADDITIONAL WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WERE NOTED OVER THE FAR SE GULF EXTENDING OVER THE DRY TORTUGAS AND THE FLORIDA KEYS. OUTSIDE OF ANY CONVECTIVE ACTIVITY...LIGHT SOUTHEAST WINDS OF 10 TO 15 KNOTS PREVAILED OVER MOST OF THE GULF. ...THE CARIBBEAN SEA... BROAD UPPER LEVEL CYCLONIC FLOW DOMINATED THE CARIBBEAN BASIN WITH PRONOUNCED TROUGHING OVER THE WESTERN CARIBBEAN SEA. THE FLOW TURNED MORE SOUTHWESTERLY OVER THE EASTERN CARIBBEAN. UPPER LEVEL SATELLITE DERIVED WINDS AND NWP MODEL DATA INDICATED WINDS OF 50-60 KT ACROSS THE CARIBBEAN S OF 15N. AN EXPANSIVE AREA OF SAHARAN AIR COVERED MOST OF THE BASIN AND GIVEN THE STRONG STABILITY IN PLACE...CONVECTION WAS GENERALLY SUPPRESSED WITH CONVECTIVE ACTIVITY CONFINED TO THE MONSOON TROUGH OVER PANAMA AND ALONG THE SOUTHERN PORTION OF A TROPICAL WAVE CURRENTLY ENTERING THE FAR E CARIBBEAN. SCATTERED SHOWERS AND THUNDERSTORMS WERE OCCURRING OVER BARBADOS...GRENADA AND THE FAR SE CARIBBEAN. THE PRESSURE GRADIENT BETWEEN HIGH PRESSURE IN THE WESTERN ATLANTIC AND LOWER PRESSURE ASSOCIATED WITH THE MONSOON TROUGH SUPPORTS 15-20 KT TRADES EXCEPT LIGHTER WINDS OF AROUND 10-15 KT OVER THE NORTH CENTRAL AND NW SECTIONS. ...HISPANIOLA... THE EFFECTS OF THE SAHARAN AIR LAYER OVER THE CARIBBEAN ARE BECOMING EVIDENT THIS AFTERNOON AS ONLY LOW CLOUDS WERE NOTED OVER HISPANIOLA. NONETHELESS AN ISOLATED LATE AFTERNOON THUNDERSTORM WAS DEVELOPING OVER THE INTERIOR OF THE DOMINICAN REPUBLIC. LITTLE CHANGE IN THIS ACTIVITY IS EXPECTED THROUGH THE NEXT 24-48 HOURS DUE TO THE PROXIMITY OF THE SAHARAN AIR LAYER IN THE AREA. ...THE ATLANTIC OCEAN... A BROAD UPPER LEVEL TROUGH EXTENDS FROM A CYCLONIC CIRCULATION 31N53W SOUTHWESTWARD ACROSS THE WESTERN ATLANTIC...HISPANIOLA INTO THE WEST CENTRAL CARIBBEAN. A MID-LEVEL TROUGH PASSES THROUGH 32N31W TO 24N40W. A SURFACE RIDGE EXTENDING FROM 31N15W TO 1029 MB HIGH CENTERED NEAR 34N40W ACROSS THE NORTHERN BAHAMAS AND SOUTHERN FLORIDA INTO THE GULF OF MEXICO DOMINATES THE ENTIRE ATLANTIC BASIN... WITH LITTLE OR NO SIGNIFICANT DEEP CONVECTION. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ COBB