000 AXNT20 KNHC 011201 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT WED AUG 01 2012 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...SPECIAL FEATURES... A TROPICAL WAVE IS ANALYZED FROM 14N44W TO A 1012 MB LOW NEAR 10N45W WITH SCATTERED MODERATE/STRONG CONVECTION FROM 8N-13N BETWEEN 43W-48W. SHOWER AND THUNDERSTORM ACTIVITY ASSOCIATED WITH THIS LOW/WAVE IS ABOUT 870 NM TO THE EAST OF THE SOUTHERN WINDWARD ISLANDS. THE PRECIPITATION CONTINUES TO SHOW SIGNS OF ORGANIZATION. ENVIRONMENTAL CONDITIONS ARE CONDUCIVE FOR GRADUAL DEVELOPMENT OF THIS LOW OVER THE NEXT FEW DAYS. THIS SYSTEM HAS A HIGH CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WESTWARD 13 TO 17 KT. INTERESTS IN THE WINDWARD ISLAND SHOULD MONITOR THE PROGRESS OF THIS SYSTEM. ...TROPICAL WAVES... TROPICAL WAVE IS ANALYZED FROM W OF THE CAPE VERDE ISLANDS NEAR 15N26W TO A 1012 MB SURFACE LOW EMBEDDED IN THE MONSOON TROUGH NEAR 11N27W MOVING W NEAR 20 KT. WAVE IS ALONG THE LEADING EDGE OF A LOW AMPLITUDE SURGE OF DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. HOWEVER...THE N PORTION OF THE WAVE IS IN DRIER AIR DUE TO SAHARAN DUST THAT COVERS THE E ATLC. NO ASSOCIATED DEEP CONVECTION. TROPICAL WAVE IS ANALYZED ALONG 73W/74W FROM 23N INTO THE CENTRAL CARIBBEAN ACROSS HAITI 12N MOVING W 10-15 KT. WAVE IS ALONG THE LEADING EDGE OF A SURGE OF DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. NO ASSOCIATED DEEP CONVECTION. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 16N16W EXTENDING ALONG 13N21W THROUGH THE 1012 MB LOW ASSOCIATED WITH THE TROPICAL WAVE DESCRIBED ABOVE CONTINUING ALONG 10N32W TO 11N37W. THE ITCZ STARTS W OF THE 1012 MB LOW IN THE SPECIAL FEATURES ABOVE NEAR 10N47W 10N53W TO INLAND OVER SOUTH AMERICA NEAR 7N59W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 10N-12N BETWEEN 52W58W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 4N-9N BETWEEN 25W-34W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER RIDGE COVERS THE GULF N OF LINE FROM NAPLES FLORIDA ALONG 22N88W TO TAMPICO MEXICO AND ANCHORED OVER NE TEXAS/S OKLAHOMA. AN UPPER TROUGH EXTENDS ACROSS THE FAR S GULF FROM AN UPPER LOW IN THE NW CARIBBEAN JUST S OF CUBA ACROSS THE YUCATAN TO OVER THE BAY OF CAMPECHE THEN NW TO TUXPAN MEXICO. A WEAK SURFACE TROUGH IS AT 01/0900 UTC IN THE W ATLC TO OVER THE FLORIDA PENINSULA. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE INLAND AND WITHIN 60 NM ALONG THE N GULF COAST BETWEEN PANAMA CITY FLORIDA AND THE CHANDELEUR ISLANDS OFF SE LOUISIANA. ISOLATED SHOWERS ARE POSSIBLE N OF 25N E OF 91W. A WEAK SURFACE RIDGE EXTENDS FROM W ATLC ACROSS S FLORIDA WITH A 1016 MB HIGH NEAR 24689W LEAVING THE REMAINDER OF THE GULF WITH FAIR WEATHER THIS MORNING. WEAK SURFACE RIDGE WILL PREVAIL ACROSS THE AREA THROUGH SUN. CARIBBEAN SEA... THE UPPER LOW IS CENTERED OFF THE SW COAST OF CUBA NEAR THE ISLE OF YOUTH EXTENDS AN UPPER TROUGH SW ACROSS THE YUCATAN PENINSULA. A BROAD UPPER RIDGE COVERS THE REMAINDER OF THE CARIBBEAN ANCHORED NEAR THE MONA PASSAGE AND EXTENDING AN UPPER RIDGE AXIS ACROSS THE CARIBBEAN TO NICARAGUA NEAR 13N84W AND E ACROSS THE LEEWARD ISLANDS INTO THE TROPICAL ATLC PROVIDING DIFFLUENCE ALOFT TO GENERATE CLUSTERS OF SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS N OF 16N TO OVER THE N CARIBBEAN BETWEEN PUERTO RICO AND W CUBA INCLUDING HISPANIOLA AND JAMAICA. THE MONSOON TROUGH EXTENDS FROM COLOMBIA ALONG 9N ACROSS THE SW CARIBBEAN AND PANAMA INTO THE E PACIFIC REGION GENERATING CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 13N W OF 75W TO INLAND OVER PANAMA TO NICARAGUA. THIS IS LEAVING THE REMAINDER OF THE CARIBBEAN WITH FAIR WEATHER THIS MORNING. TROPICAL WAVE IN THE CENTRAL CARIBBEAN WILL MOVE ACROSS THE W CARIBBEAN THROUGH FRI AND W OF THE AREA ON SAT. THE TROPICAL WAVE AND ASSOCIATED LOW IN THE SPECIAL FEATURES WILL MOVE INTO THE FAR E CARIBBEAN LATE SAT AND SUN...POSSIBLY AS A TROPICAL CYCLONE. ATLANTIC OCEAN... A NARROW UPPER TROUGH EXTENDS ALONG THE EASTERN SEABOARD TO NE FLORIDA GENERATING SCATTERED TO NUMEROUS SHOWERS/SCATTERED THUNDERSTORMS N OF 28 BETWEEN 77W-80W. A SURFACE TROUGH AT 01/0900 UTC EXTENDS FROM A WEAK 1011 MB LOW OFF THE NORTH/SOUTH CAROLINA COAST INTO THE REGION NEAR 32N80W ACROSS FLORIDA S OF ST. AUGUSTINE TO NEAR FORT MYERS. SCATTERED SHOWERS ARE WITHIN 60 NM EITHER SIDE OF THE SURFACE TROUGH. THE UPPER LOW OVER THE NW CARIBBEAN EXTENDS AN UPPER TROUGH INTO THE W ATLC ACROSS THE N BAHAMA ISLANDS TO 28N76W. A BROAD UPPER RIDGE COVERS THE AREA S OF 27N BETWEEN 55W-75W AND IS ANCHORED OVER THE MONA PASSAGE. A LARGE UPPER LOW IS CENTERED IN THE CENTRAL ATLC NEAR 27N44W AND SUPPORTING A SURFACE TROUGH THAT EXTENDS FROM 32N49W TO 25N53W. CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 24N-29N BETWEEN 43W-61W. OTHERWISE A BROAD SURFACE RIDGE DOMINATES THE ATLC WITH A 1023 MB HIGH JUST E OF BERMUDA. SATELLITE IMAGERY SHOWS A SURGE OF SAHARAN DUST COVERING THE E ATLC FROM 16N-28N E OF 40W. THE SURFACE RIDGE WILL PREVAIL OVER THE NORTHERN PART OF THE W ATLC THROUGH SUN. THE NORTHERN PORTION OF A TROPICAL WAVE IN THE CENTRAL CARIBBEAN WILL MOVE ACROSS THE S BAHAMA ISLANDS THROUGH THU NIGHT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW