000 AXNT20 KNHC 110517 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST MON DEC 11 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... METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0445 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 5N7W 3N28W 2N40W EQ51W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 75 NM OF THE AXIS FROM 4W-23W WITH CLUSTERS OF SIMILAR CONVECTION ARE FROM S OF THE EQUATOR TO INLAND OVER AFRICA E OF 9W ACROSS THE PRIME MERIDIAN. ...DISCUSSION... GULF OF MEXICO... BROAD MID/UPPER LEVEL TROUGH IS CURRENTLY OVER THE SW US AND W MEXICO AND WILL APPROACH THE W GULF BY MID WEEK. THE GULF IS NOW DOMINATED BY A MID/UPPER RIDGE WITH THE AXIS EXTENDING FROM THE CARIBBEAN INTO THE W ATLC AND COVERS THE GULF. THIS IS DRAWING TROPICAL MOISTURE N ACROSS THE E GULF TO 27N E OF 89W BRINGING SCATTERED SHOWERS AND WIDELY ISOLATED THUNDERSTORMS OVER THAT AREA. A WEAK SURFACE TROUGH EXTENDS FROM THE YUCATAN PENINSULA N TO SE LOUISIANA CAUSING A WEAKNESS IN THE SURFACE RIDGE THAT DOMINATES THE ATLC EXTENDING OVER THE E US AND GULF OF MEXICO. CARIBBEAN SEA... BROAD MID/UPPER LEVEL RIDGE DOMINATES THE CARIBBEAN ANCHORED BY AN UPPER HIGH OVER COLOMBIA EXTENDING N INTO THE W ATLC ALONG 77W. THIS IS DRAWING TROPICAL MOISTURE N ACROSS CENTRAL AMERICA AND THE W CARIBBEAN GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS W OF 79W AND N OF 18N W OF 74W. THE SURFACE TROUGH IN THE GULF OF MEXICO EXTENDS FROM OVER THE YUCATAN PENINSULA INTO THE NW CARIBBEAN TO ALONG THE COAST OF HONDURAS. STRONG EASTERLY TRADE WINDS CROSS THE CARIBBEAN. ATLANTIC OCEAN... BROAD MID/UPPER LEVEL RIDGE FROM THE CARIBBEAN NARROWS AS IT EXTENDS OVER THE W ATLC ALONG 77W COVER THE AREA W OF 73W. DEEP LAYERED TROUGH COVERS THE REMAINDER OF THE W ATLC N OF 25N BETWEEN 55W-73W. WEAK SUBTROPICAL JET IS ALONG THE BASE OF THIS UPPER TROUGH WITH THE ASSOCIATED STATIONARY FRONT EXTENDING THROUGH 32N58W SW THE THE TURKS AND CAICOS. SCATTERED SHOWERS/ THUNDERSTORMS ARE WITHIN 120 NM OF THE FRONT N OF 24N. A SECOND UPPER RIDGE EXTENDS FROM THE BROAD MID/UPPER RIDGE OF THE CARIBBEAN ACROSS THE LEEWARD ISLANDS ENE ALONG 23N56W TO BEYOND 32N44W. UPPER TROUGH COVERS THE REMAINDER OF THE ATLC EXTENDING FROM AN UPPER LOW OVER MOROCCO/WESTERN SAHARA ALONG 26N21W 20N32W TO THE W TROPICAL ATLC E OF THE LESSER ANTILLES NEAR 13N57W. A SURFACE TROUGH EXTENDS FROM 26N36W S TO 17N38W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 20N-25N BETWEEN 33W-40W. THE REMAINDER OF THE AREA OF THE UPPER TROUGH IS UNDER DRY UPPER AIR AND STRONG SUBSIDENCE. ALSO AT THE SURFACE...BROAD RIDGE DOMINATES THE REMAINDER OF THE ATLC. $$ WALLACE