000 AXNT20 KNHC 291750 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT THU JUN 29 2006 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN 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...WEATHER OBSERVATIONS...RADAR... AND METEOROLOGICAL ANALYSIS. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 31W SOUTH OF 10N MOVING WEST AROUND 15 KT. NO PRECIPITATION IS DIRECTLY RELATED JUST TO THIS WAVE. ITCZ SHOWERS AND THUNDERSTORMS ARE FOUND FROM 3N TO 6N BETWEEN 28W AND 33W. A TROPICAL WAVE IS ALONG 47W/48W SOUTH OF 10N MOVING WEST 10 TO 15 KT. NO SHOWERS AND THUNDERSTORMS ARE DIRECTLY RELATED JUST TO THIS WAVE. A LARGE TROPICAL WAVE IS ACROSS THE U.S. VIRGIN ISLANDS AND THE EASTERN CARIBBEAN ALONG 65W/66W SOUTH OF 20N MOVING WEST 15 TO 20 KT. THIS WAVE IS INTERACTING WITH A LARGE UPPER-LEVEL TROUGH... PRODUCING DISORGANIZED CLOUDINESS AND SHOWERS THAT EXTEND FROM THE EASTERN CARIBBEAN SEA...ACROSS THE LESSER ANTILLES...AND NORTHWARD INTO THE ATLANTIC FOR A FEW HUNDRED MILES. THESE SHOWER/TSTM ACTIVITY SHOULD SPREAD ACROSS PORTIONS OF PUERTO RICO AND HISPANIOLA FOR THE REST OF TODAY AND FRIDAY. UPPER-LEVEL WINDS REMAIN STRONG ENOUGH TO PROHIBIT ANY DEVELOPMENT OF THIS SYSTEM INTO A TROPICAL CYCLONE OVER THE NEXT COUPLE OF DAYS. THE SAN JUAN DOPPLER RADAR IS SHOWING SHOWERS WITH EMBEDDED TSTMS MOVING ACROSS THESE ISLANDS UNDER A SE WIND FLOW. BRIEF PERIODS OF LOCALLY HEAVY RAINFALL AND STRONG GUSTY WINDS...ESPECIALLY OVER HIGHER ELEVATIONS...WILL BE POSSIBLE. THERE IS A RISK OF FLASH FLOODING AND MUDSLIDES. ST. THOMAS AND ST. CROIX ARE REPORTING GUSTY WINDS UP TO 22 KT. A TROPICAL WAVE IS ALONG 96W SOUTH OF 20N MOVING WEST 10 TO 15 KT. THE NORTHERN END OF THE WAVE IS GENERATING A CLUSTER OF MODERATE/ISOLATED STRONG CONVECTION OVER THE BAY OF CAMPECHE VERY CLOSE TO VERACRUZ...WHERE 1.56 INCHES OF RAIN FELL DURING THE LAST 24 HOURS. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 7N14W 3N25W 7N35W 3N45W 5N53W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 80/100 NM ON EITHER SIDE OF THE AXIS WEST OF 40W. SIMILAR CONVECTION IS SEEN FROM 6N-10N EAST OF 20W. ...DISCUSSION... THE GULF OF MEXICO... A CUT-OFF LOW IS OVER NE MEXICO WHILE AN UPPER RIDGE FROM AN UPPER HIGH ANCHORED OVER CENTRAL AMERICA DOMINATES THE ENTIRE GULF. ABUNDANT UPPER LEVEL MOISTURE COVERS THE AREA WEST OF 90W. AT THE SURFACE...WEAK HIGH PRESSURE IS KEEPING RATHER QUIET CONDITIONS ACROSS THE GULF WITH THE EXCEPTION OF THE SW QUADRANT WHERE THERE ARE MODERATE/STRONG SHOWERS WITH EMBEDDED TSTMS THANKS TO THE PRESENCE OF A TROPICAL WAVE. A SURFACE TROUGH EXTENDS FROM THE FLORIDA PANHANDLE MAINLY WWD ALONG 28N90W TO THE TEXAS COAST. ISOLATED SHOWERS/THUNDERSTORMS ARE BEHIND THE SURFACE TROUGH WEST OF 90W. WEAK RIDGE WILL BUILD WESTWARD ACROSS THE NORTHERN GULF DURING THE NEXT FEW DAYS. THE CARIBBEAN SEA... BROAD UPPER RIDGE COVERS THE W CARIBBEAN...CENTRAL AMERICA AND THE YUCATAN PENINSULA FROM AN UPPER HIGH LOCATED OVER NICARAGUA NEAR 12N85W. THE RIDGE ALSO EXTENDS NWD ACROSS THE GULF. A MIDDLE/UPPER LEVEL TROUGH FROM THE W ATLC ENTERS THE CARIBBEAN ACROSS HISPANIOLA. THIS TROUGH IS INTERACTING WITH THE TROPICAL WAVE CURRENTLY MOVING ACROSS THE EASTERN CARIBBEAN. TROPICAL MOISTURE IS BEING ADVECTED OVER CENTRAL AMERICA AND THE NW CARIBBEAN...ENHANCING SCATTERED MODERATE/ISOLATED STRONG CONVECTION OVER EASTERN NICARAGUA...NE HONDURAS AND THE GULF OF HONDURAS. PRESSURE GRADIENT BETWEEN THE ATLC HIGH AND THE COLOMBIAN LOW IS STILL PRODUCING STRONG TRADE WINDS OFF THE COLOMBIAN COAST. A GALE WARNING IS IN EFFECT FOR THAT AREA. ANOTHER TROPICAL WAVE LOCATED EAST OF THE LESSER ANTILLES IS FORECAST TO MOVE INTO THE EASTERN CARIBBEAN ON SATURDAY. ATLANTIC OCEAN... THE SHOWER ACTIVITY BETWEEN BERMUDA AND PUERTO RICO HAS DIMINISHED. THIS ACTIVITY IS ASSOCIATED WITH A SURFACE TROUGH THAT EXTENDS FROM 31N66W TO 21N69W AND AN UPPER-LEVEL TROUGH THAT LIES ALONG 71W/72W ENTERING THE CARIBBEAN SEA ACROSS HISPANIOLA. A LARGE UPPER HIGH IN THE TROPICAL ATLC IS LOCATED NEAR 13N45W WITH AN UPPER RIDGE COVERING MOST OF THE TROPICS. THE REMAINDER OF THE E ATLC N OF 20N IS UNDER THE INFLUENCE OF AN UPPER TROUGH. AT THE SURFACE...BROAD HIGH PRESSURE COVERS MOST OF THE ATLC ANCHORED BY 1034 MB HIGH LOCATED MIDWAY BETWEEN THE AZORES AND BERMUDA. PATCHES OF LOW LEVEL CLOUDS ARE ACROSS THE OCEAN N OF 20N AND EAST OF 50W. ACCORDING TO THE 28/1500 UTC CIMSS SAHARAN AIR LAYER AND VIS SATELLITE IMAGERY A BROAD AREA OF AFRICAN DUST IS SPREADING WWD AND CURRENTLY REACHES 55W. $$ GR