000 AXNT20 KNHC 191031 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI JUN 19 2009 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 1000 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 44W S OF 7N MOVING W 5-10 KT. THIS WAVE REMAINS RELATIVELY LOW AMPLITUDE AND EMBEDDED WITHIN THE ITCZ. POSITION IS BASED ON CONTINUITY. SCATTERED MODERATE CONVECTION IS FROM 1N-2N BETWEEN 43W-44W AND FROM 4N-5N BETWEEN 42W-48W. A TROPICAL WAVE IS W OF THE BAY OF CAMPECHE INLAND OVER MEXICO ALONG 98W S OF 20N AND INTO THE E PACIFIC MOVING W NEAR 15 KT. THIS WAVE COINCIDES WITH A DEEP MOISTURE MAXIMUM PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE CONVECTION IS OVER THE FAR W BAY OF CAMPECHE S OF 22N W OF 95W WITH STRONGER CONVECTION S OF MEXICO IN THE E PACIFIC...SEE TWDEP FOR DETAILS. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 10N14W 8N24W 4N33W 4N42W AND INTO NE BRAZIL NEAR 2N51W. SCATTERED MODERATE/ ISOLATED STRONG CONVECTION IS FROM 3N-6N BETWEEN 8W-15W AND FROM 11N-14N BETWEEN 16W-19W. SCATTERED MODERATE CONVECTION IS FROM 8N-10N BETWEEN 19W-27W AND FROM 4N-6N BETWEEN 21W-23W. ISOLATED MODERATE CONVECTION IS WITHIN 200 NM N OF THE AXIS BETWEEN 28W-42W. ...DISCUSSION... GULF OF MEXICO... A TROPICAL WAVE W OF THE BAY OF CAMPECHE IS SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS S OF 22N W OF 95W...SEE ABOVE. AN AMPLIFIED UPPER RIDGE EXTENDS ACROSS THE WRN GULF WITH AXIS ALONG THE E COAST OF MEXICO CONTINUING ALONG THE COAST OF TEXAS. A TILTED UPPER LEVEL TROUGH IS OVER THE S GULF OF MEXICO EXTENDING W FROM AN UPPER LEVEL LOW OVER W CUBA TO THE COAST OF MEXICO NEAR 25N97W. UPPER LEVEL DIFFLUENCE BETWEEN THE RIDGE AXIS AND THE TROUGH IS SUPPORTING A SURFACE TROUGH OVER N FLORIDA...HOWEVER ANY ASSOCIATED SHOWERS AND THUNDERSTORMS HAVE NOW DISSIPATED. ELSEWHERE...A STATIONARY 1015 MB SURFACE HIGH NEAR 28N88W IS BRINGING TRANQUIL WEATHER ACROSS THE REMAINDER OF THE GULF OF MEXICO. ANTICYCLONIC FLOW DOMINATES THE REGION EXCEPT FOR A PORTION IN THE FAR NW GULF WHERE SE TO S 15-20 KT WINDS ARE PRESENT W OF 95W. EXPECT THE SURFACE HIGH TO CONTINUE THROUGH THE WEEKEND THEN WEAKEN ALLOWING A WEAK COLD FRONT TO MOVE SWD THROUGH THE E WATERS LATE MONDAY AND TUESDAY. CARIBBEAN SEA... UPPER LEVEL DIFFLUENCE NEAR AN UPPER LEVEL LOW S OF W CUBA NEAR 21N81W IS SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS S OF 19N W OF 87W AND INLAND OVER BELIZE AND GUATEMALA AS WELL AS S OF 12N BETWEEN 75W-84W INCLUDING PORTIONS OF PANAMA. UPPER LEVEL TROUGHING DOMINATES THE REMAINDER OF THE NW AND CENTRAL CARIBBEAN W OF 68W AS MODERATELY DRY NWLY FLOW ALOFT IS IN PLACE. HOWEVER...LOW-LEVEL INSTABILITY IS GENERATING ISOLATED SHOWERS/THUNDERSTORMS S OF CUBA FROM 19N-22N BETWEEN 78W-85W. E OF 68W...MOIST SWLY FLOW ALOFT IS GENERATING SCATTERED HIGH CLOUDS AND SUPPORTING ISOLATED SHOWERS ACROSS THE E CARIBBEAN. ATLANTIC OCEAN... A DEEP LAYER CENTRAL ATLC TROUGH IS SUPPORTING A COLD FRONT THAT ENTERS THE DISCUSSION AREA NEAR 32N50W AND EXTENDS W-SW TO 30N57W CONTINUING AS A STATIONARY FRONT TO 31N65W...THEN A WARM FRONT TO 32N67W. SCATTERED SHOWERS ARE SUPPORTED BY THE SERIES OF FRONTS N OF 30N BETWEEN 61W-67W. A SURFACE TROUGH EXTENDS ACROSS N FLORIDA FROM 30N83W TO 32N80W. ANY ASSOCIATED SHOWERS WITH THIS TROUGH HAVE NOW DISSIPATED. UPPER LEVEL DIFFLUENCE AROUND THE UPPER LEVEL LOW S OF W CUBA THAT IS SUPPORTING ISOLATED SHOWERS/THUNDERSTORMS ACROSS THE N CARIBBEAN IS ALSO SUPPORTING SIMILAR ACTIVITY ACROSS THE BAHAMAS S OF 25N W OF 74W. ACROSS THE MAJORITY OF THE CENTRAL AND E ATLC A BROAD SURFACE RIDGE DOMINATES ANCHORED BY A 1030 MB SURFACE HIGH N OF THE DISCUSSION AREA NEAR 42N24W. HOWEVER...A DEEP LAYER LOW OVER THE NE ATLC IS ASSOCIATED WITH A 1014 MB SURFACE LOW NW OF THE CANARY ISLANDS NEAR 31N17W. SHOWERS ASSOCIATED WITH THE SURFACE LOW HAVE NOW MOVED N OF THE DISCUSSION AREA. $$ WALTON