000 AXNT20 KNHC 182311 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU MAY 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2245 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 73W/74W S OF 13N MOVING W 5-10 KT. WAVE IS ILL-DEFINED WITH THE MAJORITY OF THE WAVE INLAND OVER SOUTH AMERICA. ASSOCIATED DEEP CONVECTION IS INLAND OVER COLOMBIA. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 6N8W 4N14W 4N22W 1N38W 1N51W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE WITHIN 120/150 NM EITHER SIDE OF THE AXIS FROM 8W-20N. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 120 NM EITHER SIDE OF THE AXIS FROM 31W-43W. ...DISCUSSION... GULF OF MEXICO... DEEP LAYERED TROUGH CONTINUES TO GIVE NE US SHOWERS WITH THE UPPER TROUGH COVERING THE N GULF N OF 26N. THE ASSOCIATED COLD FRONT HAS COMPLETELY CLEARED THE GULF OF MEXICO. THE S GULF IS UNDER SW UPPER FLOW DUE TO THE BROAD UPPER HIGH THAT EXTENDS FROM THE CARIBBEAN TO OVER THE CENTRAL ATLC. STRONG SUBSIDENCE AND DRY CONTINENTAL AIR COVERS THE N GULF WITH A WEAK 1018 MB HIGH OFF THE COAST OF MEXICO NEAR 24N93W. MOSTLY CLEAR SKIES AND NO SHOWER ACTIVITY DOMINATES THE GULF WITH SOME UPPER LEVEL MOISTURE BEING ADVECTED OVER THE W GULF. CARIBBEAN SEA... A COLD FRONT THAT EXTENDS ACROSS THE W ATLC ENTERS THE CARIBBEAN ACROSS CUBA NEAR 21N77W TO JUST W OF JAMAICA WHERE IT DISSIPATES IN THE SW CARIBBEAN NEAR 10N82W. A SHARP UPPER RIDGE COVERS THE CENTRAL CARIBBEAN...E OF THE FRONT...IS ANCHORED BY AN UPPER HIGH N OF COLOMBIA NEAR 13N72W WITH THE UPPER RIDGE EXTENDING ACROSS HISPANIOLA INTO THE CENTRAL ATLC. THUS...CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION HAVE DEVELOPED ACROSS THE CENTRAL CARIBBEAN E OF THE FRONT N OF 17N TO 70W AND W OF THE FRONT S OF 13N TO INLAND OVER COSTA RICA AND NICARAGUA. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS DOT THE REMAINDER OF THE W CARIBBEAN BETWEEN 71W-85W. AN UPPER TROUGH OVER THE CENTRAL ATLC EXTENDS S DEEP INTO THE TROPICS INCLUDING THE FAR E CARIBBEAN E OF 63W. DRY AIR CONTINUES TO DOMINATE THE FAR E CARIBBEAN WITH MODERATE TRADEWINDS OVER THE AREA. ATLANTIC OCEAN... DEEP LAYERED TROUGH OVER THE E US AND THE FAR W ATLC WITH THE ASSOCIATED COLD FRONT ENTERING THE AREA JUST E OF BERMUDA NEAR 32N64W SW ALONG 27N70W TO ACROSS CUBA NEAR 21N77W. SCATTERED MODERATE/STRONG CONVECTION ARE E OF THE FRONT TO A LINE FROM HISPANIOLA NEAR 20N70W TO BEYOND 32N58W. UPPER RIDGE OVER THE W CENTRAL ATLC EXTENDS FROM THE UPPER RIDGE OVER THE CARIBBEAN WITH THE AXIS ACROSS HISPANIOLA NE TO BEYOND 32N51W. BROAD UPPER LEVEL TROUGH IS OVER THE CENTRAL ATLC WITH THE AXIS EXTENDING THROUGH 32N28W THROUGH AN UPPER LOW NEAR 22N40W INTO THE DEEP TROPICS AND SOUTH AMERICA NEAR 8N61W INCLUDING THE FAR E CARIBBEAN. A SURFACE REFLECTION IN THE FORM OF A TROUGH EXTENDS FROM 28N31W ALONG 19N40W TO 16N53W. ISOLATED SHOWERS ARE WITHIN 120 NM OF THE UPPER LOW. AN UPPER RIDGE EXTENDS OVER THE E ATLC FROM AN UPPER HIGH OFF THE COAST OF AFRICA NEAR 8N19W N TO THE CANARY ISLANDS AND WNW TO 12N34W. THIS IS LEAVING THE E ATLC MAINLY SHOWER FREE. $$ WALLACE