000 AXNT20 KNHC 201054 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT WED JUN 20 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND THE 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. ...TROPICAL WAVES... AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 34W SOUTH OF 11N MOVING WEST 15 KT. NO DEEP CONVECTIVE PRECIPITATION ACCOMPANIES THIS WAVE IN THE ITCZ OR AWAY FROM THE ITCZ. AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 63W/64W SOUTH OF 19N MOVING WEST 10 TO 15 KT. UPPER LEVEL SOUTHWESTERLY WIND FLOW FROM A RIDGE CUTS ACROSS THE TOP OF THIS WAVE. ISOLATED MODERATE SHOWERS FROM 13N TO 20N BETWEEN 58W AND 70WW. IT EASY TO FORECAST THAT THE PRECIPITATION AROUND THIS WAVE WILL CONTINUE AS THE WAVE MOVES WESTWARD ACROSS THE OPEN WATERS OF THE REST OF THE CARIBBEAN SEA. A TROPICAL WAVE IS ALONG 89W/90W SOUTH OF 15N MOVING WEST 10 TO 15 KNOTS. THE WAVE GOES FROM EASTERN GUATEMALA TO WESTERN EL SALVADOR INTO THE EASTERN PACIFIC OCEAN. ISOLATED MODERATE SHOWERS ARE IN EASTERN GUATEMALA. ISOLATED MODERATE SHOWERS IN A SMALL AREA HAVE MOVED FROM CENTRAL EL SALVADOR INTO THE WATERS OF THE EASTERN PACIFIC OCEAN...AND INCREASED IN INTENSITY TO STRONG SHOWERS AND THUNDERSTORMS FROM 13N TO 14N BETWEEN 91W AND 92W. ...THE ITCZ... FROM THE SIERRA LEONE COAST NEAR 9N13W TO 6N23W TO 5N33W 4N47W... ACROSS FRENCH GUIANA TO SURINAME AND GUYANA NEAR 6N58W. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS FROM 6N TO 10N BETWEEN 19W AND 27W. ISOLATED MODERATE SHOWERS FROM 5N TO 9N BETWEEN 14W AND 19W...AND WITHIN 120 NM ON EITHER SIDE OF 6N32W 5N42W 5N52W...AND WITHIN 30 NM ON EITHER SIDE OF 5N52W 8N60W. ...DISCUSSION... THE GULF OF MEXICO... A MIDDLE TO UPPER LEVEL CYCLONIC CIRCULATION CENTER IS IN MEXICO NEAR 25N105W. ISOLATED MODERATE SHOWERS FROM 18N TO 25N BETWEEN 98W AND 104W. UPPER LEVEL ANTICYCLONIC FLOW COVERS THE GULF OF MEXICO WEST OF 90W. A CYCLONIC CIRCULATION CENTER IS DEVELOPING NEAR 26N87W. A MIDDLE TO UPPER LEVEL TROUGH STILL IS OVER THE U.S.A. EAST OF THE MISSISSIPPI RIVER. THIS TROUGH IS FORECAST TO MOVE TO THE SOUTH AND SOUTHEAST AND COVER THE SOUTHEASTERN U.S.A. FOR THE NEXT FEW DAYS. ISOLATED MODERATE SHOWERS TO LOCALLY STRONG THUNDERSTORMS FROM 18N TO 28N ACROSS MEXICO. THE PRESSURE PATTERN IN THE AREA IS WEAK AGAIN. A SURFACE RIDGE GOES FROM THE NORTHEASTERN GULF WATERS TO THE NORTHWESTERN CORNER OF THE AREA. THE CARIBBEAN SEA... THE MIDDLE TO UPPER LEVEL DRY AND STABLE AIR IN THE CARIBBEAN SEA FROM 10N TO 20N BETWEEN 60W AND 80W DURING THE LAST FEW DAYS IS BEING OVERRUN THIS MORNING BY UPPER LEVEL MOISTURE FROM NORTHEASTERN SOUTH AMERICA IN THE SOUTH CENTRAL AND SOUTHEASTERN SECTIONS OF THE AREA...AND BY AN AREA OF SURFACE LOW PRESSURE AND THE DEEP LAYER MOISTURE SURROUNDING IT IN THE SOUTHWESTERN CORNER OF THE AREA. A MIDDLE TO UPPER LEVEL TROUGH EXTENDS FROM A CYCLONIC CIRCULATION CENTER NEAR 25N75W TO SOUTHEASTERN CUBA NEAR 20N75W. UPPER LEVEL DIFFLUENT FLOW IS IN THE NORTH CENTRAL TO NORTHWESTERN SECTIONS OF THE CARIBBEAN SEA DUE TO THE UPPER LEVEL NORTHERLY WIND FLOW FROM THE GULF OF MEXICO REACHING THIS AREA AND THE UPPER LEVEL CYCLONIC FLOW AROUND THE 25N75W 20N75W TROUGH. A FEW SHOWERS FROM 17N TO 20N BETWEEN 75W AND 83W. UPPER LEVEL ANTICYCLONIC WIND FLOW COVERS THE AREA WEST OF 80W... THANKS TO SOUTHWESTERN GULF OF MEXICO RIDGE. THE ATLANTIC OCEAN... THE WESTERN ATLANTIC OCEAN DEEP LAYER TROUGH REMAINS...IN ORDER TO SUPPORT A COLD FRONT TO THE NORTH OF OUR AREA... AND A SURFACE TROUGH NOW FROM 31N53W TO 25N64W. THIS SURFACE TROUGH IS IN THE MIDDLE OF A 1020 MB HIGH PRESSURE CENTER NEAR 25N46W...AND A SECOND 1022 MB HIGH PRESSURE CENTER NEAR 28N71W. ISOLATED MODERATE SHOWERS WITHIN 60 NM ON EITHER SIDE OF THE LINE THROUGH 31N46W 27N54W 25N63W 26N75W. UPPER LEVEL ANTICYCLONIC FLOW COVERS THE ATLANTIC OCEAN NORTH OF 20N EAST OF 40W. THIS ANTICYCLONIC FLOW IS ON TOP OF A MIDDLE LEVEL CYCLONIC CIRCULATION CENTER NEAR 25N25W. $$ MT