000 AXNT20 KNHC 181048 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU MAR 18 2010 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC... ...ITCZ... ITCZ AXIS IS CENTERED ALONG 7N10W 3N24W 1N33W 2N44W CROSSING THE EQUATOR INTO SOUTH AMERICA NEAR 50W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 90 NM EITHER SIDE OF THE ITCZ FROM 19W-25W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER LOW COVERS THE SE US AND THE N GULF WITH SHORTWAVE UPPER TROUGHS ROTATING AROUND A CENTRAL POINT OVER SOUTH CAROLINA. A SHORTWAVE UPPER TROUGH IS MOVING S INTO THE NW GULF AND THE LOWER MISSISSIPPI VALLEY SUPPORTING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 60 NM OF LINE FROM 26N85W TO ALONG THE COAST OF LOUISIANA NEAR 29N91W. ISOLATED SHOWERS DOT THE REMAINDER OF THE E GULF E OF 90W. THE SECOND UPPER TROUGH IS IN THE W ATLC. NEAR ZONAL WESTERN UPPER FLOW THAT COVERS THE REMAINDER OF THE GULF IS ENHANCING A JETSTREAM WITH WINDS OF 90 TO 115 KT WITHIN 200/250 NM OF LINE FROM TEXAS NEAR CORPUS CHRISTI ALONG 24N88W TO ACROSS FLORIDA NEAR 25N80W. SOUTHERLY RETURN FLOW WILL SET UP OVER THE NW GULF TODAY SPREADING E ACROSS THE ENTIRE GULF BY SAT MORNING IN ADVANCE OF NEXT COLD FRONT MOVING OFF THE TEXAS COAST SAT. CARIBBEAN SEA... THE NORTHERLY SURFACE FLOW FROM THE GULF OF MEXICO EXTENDS S OVER THE W CARIBBEAN AND COMBINED WITH THE EASTERLY TRADE WINDS ACROSS THE REMAINDER OF THE CARIBBEAN IS GENERATING DENSE LOW LEVEL CLOUDS WITH SCATTERED SHOWERS S OF 20N W OF 81W AND ISOLATED SHOWERS DOTTING THE REMAINDER OF THE W CARIBBEAN N OF 13N W OF 76W. THE REMNANTS OF A STATIONARY FRONT EXTEND OVER THE VIRGIN ISLANDS TO ALONG THE S COAST OF THE DOMINICAN REPUBLIC WITH A SURFACE TROUGH EXTENDING FROM NEAR THE FRONT OVER THE VIRGIN ISLANDS SW TO 14N72W. ISOLATED SHOWERS ARE WITHIN 30 NM EITHER SIDE FOR THE FRONT/TROUGH. BROAD UPPER RIDGE DOMINATES THE CARIBBEAN ANCHORED OVER E VENEZUELA AND EXTENDS INTO THE W ATLC AND OVER THE TROPICAL ATLC TO 45W. THIS UPPER FLOW IS DRAWING TROPICAL MOISTURE N OVER THE S CARIBBEAN AND IS PRODUCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 15N TO INLAND OVER SOUTH AMERICA BETWEEN 70W-78W. ATLANTIC OCEAN... BROAD UPPER LOW COVERS THE SE US AND THE N GULF OF MEXICO INTO THE W ATLC WITH SHORTWAVE UPPER TROUGHS ROTATING AROUND A CENTRAL POINT OVER SOUTH CAROLINA. THE EASTERN MOST SHORTWAVE IS ALONG THE COAST FROM NORTH CAROLINA TO GEORGIA SUPPORTING A 1008 MB LOW OFFSHORE NEAR 31N77W AND A SURFACE TROUGH EXTENDING S OVER THE N BAHAMA ISLANDS TO THE N COAST OF CUBA NEAR 23N81W. A SECOND SURFACE TROUGH EXTENDS N OUT OF THE REGION. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 28N-32N BETWEEN 74W-80W WITH ISOLATED SHOWERS COVERING THE REMAINDER OF THE AREA W OF 60W. A WEAK 1016 MB HIGH IS TO THE NE OF THE CENTRAL BAHAMAS NEAR 26N65W AS THE BROAD UPPER RIDGE THAT DOMINATES THE CARIBBEAN EXTENDS AN AXIS ACROSS THE TROPICAL ATLC NEAR 10N58W TO NEAR 32N60W. A JETSTREAM WITH WINDS OF 90 TO 115 KT IS N OF LINE FROM ACROSS CUBA NEAR 21N75W 25N53W TO BEYOND 32N26W. AN UPPER TROUGH IS OVER THE CENTRAL ATLC N OF 27N BETWEEN 30W-50W SUPPORTING A COLD FRONT THAT ENTERS THE REGION NEAR 32N31W EXTENDING SW ALONG 23N45W TO 19N58W WHERE IT BECOMES STATIONARY TO OVER THE VIRGIN ISLANDS AND ALONG THE S COAST OF THE DOMINICAN REPUBLIC. ISOLATED SHOWERS ARE WITHIN 60 NM SE OF THE COLD FRONT AND WITHIN 30 NM EITHER SIDE FOR THE STATIONARY FRONT. AN UPPER RIDGE AXIS EXTENDS FROM THE BROAD UPPER RIDGE OVER THE TROPICAL ATLC THROUGH 16N45W TO BEYOND 32N20W PROVIDING DIFFLUENCE ALOFT TO GENERATE ISOLATED SHOWERS WITHIN 120 NM OF LINE FROM 27N33W TO BEYOND 32N27W. A SURFACE RIDGE DOMINATES THE E ATLC EXTENDING OVER THE CANARY ISLANDS TO A 1019 MB HIGH NEAR 22N29W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALLACE