000 AXNT20 KNHC 181144 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE JUL 18 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...TROPICAL WAVES... THE TROPICAL WAVE THAT WAS PREVIOUSLY ALONG 31W IS RELOCATED JUST S OF THE CAPE VERDE ISLANDS ALONG 25W...BASED ON VIS SATELLITE IMAGERY THIS MORNING AND COMPUTER MODELS. SIGNIFICANT DEVELOPMENT OF THIS SYSTEM IS NOT LIKELY OVER THE NEXT COUPLE OF DAYS AS IT MOVES WESTWARD AT 15 TO 20 MPH. SCATTERED MODERATE CONVECTION IS ASSOCIATED WITH THE WAVE FROM 11N-14N BETWEEN 22W-25W. TROPICAL WAVE IS ACROSS THE U.S. VIRGIN ISLANDS ALONG 65W S OF 20N MOVING W 15-20 KT. THE WAVE IS STILL INTERACTING WITH AN UPPER LOW CENTERED NEAR 26N62W. CONVECTIVE ACTIVITY HAS INCREASED ALONG THE WAVE AXIS ACROSS THE CARIBBEAN. THE SAN DOPPLER RADAR IS SHOWING SCATTERED TO NUMEROUS SHOWERS WITH EMBEDDED TSTMS WITHIN AROUND 80 NM SE OF THE SE PORTION OF THE ISLAND. THIS FEATURE IS ALSO PRODUCING SHOWERS AND TSTMS OVER NE VENEZUELA. THE WAVE WILL CROSS PUERTO RICO TODAY... ENHANCING THE SHOWER ACTIVITY OVER THAT AREA. TROPICAL WAVE IN THE W CARIBBEAN SEA IS ALONG 86W S OF 21N MOVING W 15-20 KT. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE BEHIND THE WAVE AXIS OVER THE SW CARIBBEAN FROM 11N-15N BETWEEN 77W AND THE ATLC COAST OF NICARAGUA. SCATTERED MODERATE CONVECTION IS OVER THE GULF OF HONDURAS. A DIFLUENT PATTERN ALOFT IS ENHANCING THIS CONVECTIVE ACTIVITY. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 14N17W 9N30W 7N40W 8N50W 11N60W. OUTSIDE OF TROPICAL WAVES...SCATTERED MODERATE CONVECTION IS FROM 5N-8N BETWEEN 38W-42W AND BETWEEN 47W-56W. ...DISCUSSION... GULF OF MEXICO... A 1013 MB LOW IS OVER CENTRAL MISSISSIPPI NEAR 33N89W. A SURFACE TROUGH EXTENDS E TO CENTRAL GEORGIA NEAR 33N82W. A 1017 MB HIGH IS OVER NORTH FLORIDA NEAR 29N82W. PRES GRADIENT REMAINS VERY WEAK ACROSS THE ENTIRE GULF WITH LIGHT WINDS THROUGHOUT. THE AREA IS RELATIVELY FREE OF CONVECTION THANKS TO MODERATE TO STRONG SUBSIDENCE ALOFT. ELY UPPER LEVEL FLOW DOMINATES THE GULF. AN UPPER LOW IS CENTERED OVER THE ISTHMUS OF TEHUANTEPEC IN MEXICO. AN UPPER HIGH IS OVER THE TEXAS COAST WITH A RIDGE EXTENDING MOSTLY E ACROSS FLORIDA AND THE W ATLC. SCATTERED MODERATE CONVECTION IS OVER THE NORTHERN GULF WATERS JUST SOUTH OF LOUISIANA. ISOLATED SHOWERS ARE OVER THE BAY OF CAMPECHE. SHOWER AND TSTM ACTIVITY WILL INCREASE TODAY OVER THE YUCATAN PENINSULA...NORTHERN CENTRAL AMERICA AND THE BAY OF CAMPECHE WITH THE PASSAGE OF A TROPICAL WAVE AND THE PRESENCE OF THE UPPER LOW MENTIONED ABOVE. CARIBBEAN SEA... A TINY UPPER LEVEL LOW IS OVER THE YUCATAN CHANNEL/WESTERN CUBA. AN UPPER RIDGE COVERS THE W-CENTRAL CARIBBEAN WHILE AN UPPER TROUGH CROSSES THE E CARIBBEAN FROM THE LOW LOCATED NEAR 26N62W. ABUNDANT UPPER LEVEL MOISTURE IS OVER THE BASIN. TYPICAL SURFACE TRADEWINDS OF 15-20 KT DOMINATES THE AREA WITH THE STRONGEST WINDS NEAR THE COAST OF COLOMBIA AND VENEZUELA. OUTSIDE THE CONVECTIVE ACTIVITY RELATED TO THE TROPICAL WAVES ALONG 65W AND 86W...NO OTHER AREA OF DEEP CONVECTION IS OBSERVED. THE TRADE WINDS ARE EXPECTED TO INCREASE ACROSS THE CENTRAL CARIBBEAN ON WEDNESDAY. ATLANTIC OCEAN... CLOUDINESS WITH EMBEDDED MODERATE CONVECTION BETWEEN THE NORTHERN LEEWARD ISLANDS AND BERMUDA ARE ASSOCIATED WITH A TROPICAL WAVE MOVING ACROSS THE EASTERN CARIBBEAN WHICH IS INTERACTING WITH AN UPPER LOW CENTERED NEAR 26N62W. SURFACE PRESSURES REMAIN HIGH IN THE AREA AND TROPICAL CYCLONE FORMATION IS NOT EXPECTED. A SURFACE TROUGH...REFLECTION OF THE UPPER LOW HAS DEVELOPED OVER THAT AREA AND EXTENDS FROM 28N57W TO 22N61W. ON THE TAIL END OF THE TROUGH THERE IS A CLUSTER OF MODERATE CONVECTION. A BROAD AREA OF LOW PRESSURE IS LOCATED A COUPLE HUNDRED MILES SOUTHEAST OF THE COAST OF NORTH CAROLINA. ALTHOUGH THE LOW IS CURRENTLY NOT WELL-ORGANIZED...THERE IS A POTENTIAL FOR A TROPICAL DEPRESSION TO FORM DURING THE NEXT DAY OR TWO. A SURFACE TROUGH EXTENDS SW FROM THIS LOW TO THE FLORIDA PENINSULA JUST SOUTH OF LAKE OKEECHOBEE. A 1030 MB HIGH OVER THE ATLANTIC NEAR 35N46W CONTINUES TO PRODUCE MAINLY ELY SURFACE FLOW WITH FAIR WEATHER FROM 15N-30N BETWEEN 20W-50W. IN THE UPPER LEVELS...A RIDGE IS OVER THE W ATLANTIC N OF 24N AND W OF 70W. A LOW IS FURTHER E NEAR 26N62W. A LARGE HIGH IS OVER THE E ATLANTIC NEAR 20N27W. $$ GR