000 AXNT20 KNHC 252348 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE MAY 25 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC... ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 26W S OF 8N MOVING W AT 10-15 KT. BROAD CYCLONIC FLOW IS EVIDENT ABOUT THE WAVE AXIS AS IT LIES WITHIN A MAXIMUM OF DEEP LAYER MOISTURE IN THE TOTAL PRECIPITABLE WATER IMAGERY. ISOLATED MODERATE CONVECTION IS FROM 4N-8N BETWEEN 24W-29W. TROPICAL WAVE IS ALONG 41W S OF 8N MOVING W AT 15-20 KT. LOW-LEVEL CYCLONIC FLOW IS EVIDENT IN THE VICINITY OF THE WAVE AXIS AND ALSO COINCIDES WITH A MAXIMUM IN DEEP LAYER MOISTURE MOVING ACROSS THE CENTRAL TROPICAL ATLC. WIDELY SCATTERED MODERATE CONVECTION IS FROM 4N-9N BETWEEN 36W-43W. TROPICAL WAVE IS ALONG 60W S OF 12N MOVING W AT 15-20 KT. THE NORTHERN EXTENT OF MAXIMUM TOTAL PRECIPITABLE WATER IS NOTED MOVING OVER TRINIDAD AND TOBAGO THIS EVENING AS WELL AS THE FAR SE CARIBBEAN SEA. INCREASED LOW-LEVEL MOISTURE IS GENERATING WIDELY SCATTERED MODERATE CONVECTION FROM 8N-12N BETWEEN 56W-63W. FARTHER SOUTH...INLAND OVER NORTHERN S AMERICA...THE WAVE ALONG WITH DAYTIME HEATING AND ATMOSPHERIC INSTABILITY IS GENERATING SCATTERED MODERATE/ISOLATED STRONG CONVECTION FROM THE EQUATOR TO 7N BETWEEN 53W-65W. TROPICAL WAVE IS INLAND OVER WESTERN VENEZUELA AND EASTERN COLOMBIA EXTENDING FROM 11N71W TO 1N70W MOVING W AT 10-15 KT. AN UPPER LEVEL TROUGH LOCATED OVER THE WESTERN CARIBBEAN WITH AXIS ALONG 78W CONTINUES TO FRACTURE ENERGY AND MOISTURE N-NE FROM THE WAVE. THIS MOISTURE ALONG WITH INSTABILITY IS GENERATING SCATTERED MODERATE CONVECTION OVER THE SOUTH-CENTRAL CARIBBEAN FROM 10N-13N BETWEEN 67W-73W. THIS WAVE IS EXPECTED TO BEGIN LOSING IDENTITY AS IT SLOWS AND MOVES WESTWARD INTO SOUTHWESTERLY MONSOONAL FLOW CURRENTLY LOCATED OVER THE SE PACIFIC REGION. TROPICAL WAVE EXTENDS FROM 14N80W ACROSS CENTRAL PANAMA TO COLOMBIA NEAR 3N76W MOVING W AT 5-10 KT. VERY MUCH LIKE THE WAVE TO THE EAST PREVIOUSLY MENTIONED...THIS WAVE CONTINUES TO FRACTURE ENERGY AND MOISTURE TO THE NE DUE TO THE UPPER LEVEL TROUGH ACROSS THE WESTERN CARIBBEAN. WITH THE SOUTHWESTERLY MONSOONAL FLOW IN PLACE ACROSS THE SE PACIFIC...THIS WAVE WILL BEGIN TO LOSE IDENTITY AS IT MOVES WESTWARD OVER THE NEXT COUPLE OF DAYS. ISOLATED MODERATE CONVECTION IS WITHIN 120 NM OF THE WAVE AXIS. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N13W 5N19W 4N34W 8N58W. ISOLATED MODERATE CONVECTION IS FROM 4N-8N BETWEEN 10W-16W. ...DISCUSSION... GULF OF MEXICO... MOST OF THE GULF OF MEXICO REMAINS DRY AND CLEAR THIS EVENING UNDER THE INFLUENCE OF NW UPPER LEVEL FLOW AND DRY AIR ALOFT ACROSS THE BASIN EAST OF AN UPPER LEVEL RIDGE AXIS EXTENDING FROM THE E PACIFIC ACROSS SOUTHERN MEXICO TO THE LOWER MISSISSIPPI RIVER VALLEY. AT THE SURFACE...WEAK ANTICYCLONIC SURFACE FLOW COVERS THE REGION...HOWEVER...A WEAK SURFACE TROUGH FROM NEAR GULFPORT MISSISSIPPI TO 27N87W CREATES A WEAKNESS IN THE RIDGE GENERATING ISOLATED SHOWERS AND TSTMS N OF 29N BETWEEN 87W-91W. ALSO... SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING OVER THE FLORIDA PENINSULA AND NE GULF...AND ARE LIKELY ASSOCIATED WITH DAYTIME HEATING AND INSTABILITY ALONG WITH MOISTURE WRAPPING AROUND THE NORTH AND WESTERN PERIPHERY OF A BROAD LOW PRESSURE SYSTEM IN THE W ATLC. CARIBBEAN SEA... THE NW CARIBBEAN IS EXPERIENCING GENERALLY FAIR WEATHER INFLUENCED BY DRY AIR ALOFT DUE TO NW FLOW WEST OF AN UPPER LEVEL TROUGH WITH AXIS ALONG 78W. EAST OF THE UPPER LEVEL TROUGH AXIS HOWEVER...MIDDLE TO UPPER LEVEL MOISTURE CONTINUES TO ADVECT N-NE ACROSS MUCH OF THE CENTRAL CARIBBEAN INCLUDING EASTERN CUBA...HISPANIOLA...AND PUERTO RICO GENERATING NUMEROUS SHOWERS AND SCATTERED TSTMS BETWEEN 65W-80W. HEAVY PRECIPITATION IS FORECAST TO PERSIST OVER INTERIOR PORTIONS OF HAITI AND THE DOMINICAN REPUBLIC THROUGH THE OVERNIGHT HOURS SHIFTING SLOWLY EASTWARD THROUGH THE WEEK ACROSS THE MONA PASSAGE AND PUERTO RICO. GLOBAL MODELS INDICATE THE UPPER LEVEL TROUGHING WILL SLOWLY LIFT NORTHWARD INTO THE SW NORTH ATLC REMAINING N OF 20N BY THE END OF THE WEEK. ATLANTIC OCEAN... AN UPPER LEVEL CYCLONIC CIRCULATION IS CENTERED NEAR 31N74W AND SUPPORTS A BROAD AREA OF SURFACE LOW PRESSURE. THE 1006 MB LOW IS CENTERED NEAR 31N73W AND EXTENDS A SURFACE TROUGH TO 27N65W. THE SYSTEM REMAINS RATHER DISORGANIZED WITH REGARDS TO SIGNIFICANT DEEP CONVECTION...HOWEVER...A TIGHT PRESSURE GRADIENT IS LOCATED IN THE NE QUADRANT OF THE LOW WITH WINDS TO GALE FORCE NORTH OF THE DISCUSSION AREA THIS EVENING. WITH LOW-LEVEL MOISTURE WRAPPING AROUND THE NORTH AND WESTERN SIDES OF THE LOW...SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING N OF 31N BETWEEN 75W-80W AND OVER PORTIONS OF THE FLORIDA PENINSULA AND ADJACENT COASTAL WATERS. SE OF THE LOW...AN UPPER LEVEL TROUGH AXIS IS ALONG 78W THAT EXTENDS FROM THE SW CARIBBEAN SEA NORTHWARD TO THE NW BAHAMAS. EAST OF THE UPPER LEVEL TROUGH...MIDDLE TO UPPER LEVEL MOISTURE IS ADVECTING NE BRINGING ISOLATED SHOWERS OVER THE W ATLC S OF 26N BETWEEN 60W-72W. FARTHER EAST...UPPER LEVEL DIFFLUENCE OVER THE CENTRAL ATLC IS SUPPORTING SCATTERED SHOWERS FROM 21N-31N BETWEEN 45W-60W. A SURFACE RIDGE DOMINATES THE REMAINDER OF THE CENTRAL AND EASTERN ATLC E OF 45W ANCHORED BY A 1022 MB HIGH CENTERED SOUTH OF THE AZORES NEAR 34W25W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN