000 AXNT20 KNHC 221755 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT THU JUN 21 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 ADDED TO THE 1200 UTC ANALYSIS ALONG 21W SOUTH OF 12N MOVING WEST 10-15 KT. THIS WAVE IS WELL DEFINED WITH A SMALL SWIRL OF LOW CLOUDS NEAR 10N21W. AN AREA OF MODERATE SHOWERS WITH EMBEDDED TSTMS IS JUST AHEAD OF THE WAVE AXIS FROM 9N-11N BETWEEN 21W-23W. REMAINDER OF THE SHOWER ACTIVITY IS RELATED TO THE ITCZ. TROPICAL WAVE IS ALONG 56/57W S OF 17N MOVING W 15-20 KT. BROAD LOW LEVEL CURVATURE IS OBSERVED ON SATELLITE IMAGERY. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 70/90 NM ON EITHER SIDE OF THE WAVE FROM 11N-13N. REMAINDER OF THE SHOWER ACTIVITY IS RELATED TO THE ITCZ. EARLIER QUIKSCAT SHOWS MODERATE TO STRONG TRADE WINDS E OF THE MAIN AXIS. THIS WAVE IS EXPECTED TO REACH THE LESSER ANTILLES LATER TODAY AND THE U.S. VIRGIN ISLANDS AND PUERTO RICO ON FRIDAY. TROPICAL WAVE IS ALONG 81W S OF 20N MOVING W AROUND 15 KT. THIS WAVE SHOULD MOVE INTO CENTRAL AMERICA LATER TODAY AND TONIGHT ENHANCING THE CHANCES OF RAIN OVER THAT AREA. SATELLITE IMAGERY SHOWS CLUSTERS OF MODERATE TO STRONG CONVECTION OVER THE SW CARIBBEAN FROM 9N-14N BETWEEN 79W-85W. PART OF THIS CONVECTIVE ACTIVITY IS ALREADY AFFECTING THE CARIBBEAN PLAINS OF NICARAGUA AND NE HONDURAS. SIMILAR CONVECTION IS SEEN OVER THE GULF OF HONDURAS AND THE NE PORTION OF BELIZE. A DIFFLUENT PATTERN ALOFT IS ENHANCING THIS CONVECTIVE ACTIVITY. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 10N14W 5N30W 6N40 7N55W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 100-120 NM OF THE AXIS FROM 20W-33W. CLUSTERS OF SCATTERED MODERATE TO STRONG CONVECTION DOT THE AREA FROM 5N-11N BETWEEN 55W-57W JUST BEHIND THE TROPICAL WAVE THAT IS LOCATED ALONG 57W. ...DISCUSSION... GULF OF MEXICO... AN UPPER RIDGE EXTENDS FROM NE MEXICO ALONG THE TEXAS COAST WITH A SECOND UPPER RIDGE COVERING THE SE U.S. INCLUDING THE STATE OF FLORIDA AND THE FAR NE GULF N OF 26N E OF 86W. THE BROAD UPPER HIGH OVER THE CARIBBEAN ALSO DOMINATES SOUTH MEXICO...THE BAY OF CAMPECHE...THE YUCATAN PENINSULA AND THE STRAITS OF FLORIDA. AT THE SURFACE...A RIDGE EXTENDS FROM A 1022 MB HIGH LOCATED OVER SOUTH CAROLINA ALONG THE N GULF COAST TO OVER TEXAS. AS OF 1500 UTC...A SURFACE TROUGH EXTENDS FROM 23N94W TO 18N95W. AN AREA OF SHOWERS WITH EMBEDDED TSTMS IS ASSOCIATED WITH THIS FEATURE OVER THE BAY OF CAMPECHE. ONLY ISOLATED SHOWERS ARE SEEN OVER THE REMAINDER OF THE GULF. THE RIDGE ALONG THE N GULF COAST WILL WEAKEN AS A WEAK LOW PRESSURE MOVES INTO CENTRAL FLORIDA ON SATURDAY. CARIBBEAN SEA... BROAD UPPER RIDGE IS ANCHORED IN THE SW CARIBBEAN NEAR 13N82W AND DOMINATES THE ENTIRE BASIN. ABUNDANT UPPER LEVEL MOISTURE COVERS MUCH OF THE CARIBBEAN W OF 73W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE OVER THE SW CARIBBEAN AND THE GULF OF HONDURAS ASSOCIATED WITH A TROPICAL WAVE LOCATED ALONG 81W. DRY AIR IS OVER THE ABC ISLANDS AND NORTHERN VENEZUELA. STRONG TRADE WINDS OF 20-25 KT CONTINUE ACROSS MUCH OF THE S AND SW CARIBBEAN WATERS WITH MODERATE TRADES OF 10-15 KT OVER THE N CARIBBEAN. ATLANTIC OCEAN... AN AREA OF SHOWERS AND THUNDERSTORMS CONTINUES BETWEEN THE BAHAMAS AND BERMUDA IN ASSOCIATION WITH A SURFACE TROUGH THAT EXTENDS FROM 24N76W TO 32N71W AND AN UPPER-LEVEL LOW. LATEST SATELLITE IMAGERY INDICATES THAT THIS SYSTEMS HAS BECOME A LITTLE BETTER ORGANIZED...BUT UPPER LEVEL WINDS ARE CURRENTLY NOT FAVORABLE FOR TROPICAL CYCLONE DEVELOPMENT. THIS SYSTEM WILL LIKELY MOVE TOWARD THE WEST-NORTHWEST OVER THE NEXT 24 HOURS OR SO. ANOTHER SURFACE TROUGH...REFLECTION OF A LARGE UPPER LOW IS ALONG 32N50W 26N55W 20N60W. A CLUSTER OF SHOWERS AND TSTMS IS ON THE SOUTHERN END OF THE TROUGH. ANOTHER AREA OF MAINLY SHOWERS IS AHEAD OF THE UPPER TROUGH AXIS FROM 20N-26N BETWEEN 44W-50W. THE REMAINDER OF THE ARE IS UNDER THE INFLUENCE OF A 1036 MB HIGH WELL N OF THE REGION. TYPICAL STRATOCUMULUS CLOUDS COVERS THE ATLANTIC EAST OF 44W. VISIBLE SATELLITE PICTURES AND THE SAHARAN AIR LAYER FROM CIMSS ARE STILL SHOWING A BROAD AREA OF AFRICAN DUST EAST OF 55W. IN THE UPPER LEVELS...AN UPPER RIDGE OVER THE SE U.S. ALSO AFFECT THE W ATLC N OF 26N W OF 76W. THE DEEP LAYERED TROUGH CONTINUES TO RETREAT N AND NARROW OVER THE W ATLC N OF 25N BETWEEN 70W-76W. UPPER RIDGE AXIS EXTENDS FROM THE UPPER HIGH IN THE CARIBBEAN ACROSS HISPANIOLA NEAR 19N69W TO BEYOND 32N63W. THE LARGE UPPER LOW OVER THE CENTRAL ATLC IS CENTERED NEAR 33N45W WITH THE UPPER FLOW AS FAR S AS 13N FROM 35W-60W. AN UPPER RIDGE ALONG 25W COVERS THE REMAINDER OF THE E ATLC. $$ GR