000 AXNT20 KNHC 201105 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST TUE NOV 20 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 78W S OF 18N MOVING W 10-15 KT. WAVE CONTINUES TO WEAKEN AS IT MOVES OVER THE W CARIBBEAN. ANY ACTIVITY IS ASSOCIATED WITH UPPER LEVEL FEATURES. TROPICAL WAVE IS ALONG 92W S OF 21N MOVING W 10-15 KT. WAVE IS MOSTLY IN THE E PACIFIC REGION WITH ONLY SOME ISOLATED LOW LEVEL SHOWERS OVER THE E BAY OF CAMPECHE. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 9N12W 6N26W 9N40W 8N60W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE OVER A BROAD AREA FROM 1N-11N BETWEEN 20W-40W AND IS PRODUCED BY UPPER LEVEL DIFFLUENCE AND WITHIN 90 NM OF LINE FROM 7N19W 4N8W TO THE PRIME MERIDIAN NEAR 4N. DISCUSSION... GULF OF MEXICO... UPPER LEVEL LOW IS CENTERED OVER THE S BAJA PENINSULA IN THE E PACIFIC REGION COVERING MOST OF MEXICO THE THE W COAST OF THE GULF INCLUDING SE TEXAS. A NARROW UPPER TROUGH EXTENDS FROM THE W ATLC ACROSS N FLORIDA TO OVER LOUISIANA. VERY BROAD UPPER RIDGE COVERS THE REMAINDER OF THE GULF EXTENDING FROM THE CARIBBEAN THROUGH THE YUCATAN CHANNEL TO 26N92W. A SURFACE RIDGE REMAINS OVER THE GULF ANCHORED OVER GEORGIA BY A 1024 MB HIGH. PATCHES OF LOW LEVEL CLOUDS WITH WIDELY ISOLATED SHOWERS DOTS THE ENTIRE GULF. THE NEXT COLD FRONT IS EXPECTED TO ENTER THE GULF ON THU BRINGING SHOWER ACTIVITY AND GUSTY WINDS BEHIND THE FRONT AS IT TRANSVERSES THE GULF. CARIBBEAN SEA... THE BROAD UPPER RIDGE OVER THE GULF OF MEXICO EXTENDS FROM THE CARIBBEAN ANCHORED OVER SOUTH AMERICA EXTENDING A MEAN RIDGE AXIS FROM COLOMBIA THROUGH THE YUCATAN CHANNEL COVERING THE ENTIRE CARIBBEAN. THE UPPER DIFFLUENCE IS GENERATING NUMEROUS SHOWERS/SCATTERED THUNDERSTORMS OVER THE W CARIBBEAN FROM 10N-18N BETWEEN 80W-86W INCLUDING PORTIONS OF CENTRAL AMERICA. THE ITCZ AXIS EXTENDS ACROSS SOUTH AMERICA AND PANAMA INTO THE E PACIFIC REGION ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 11N E OF 81W TO INLAND OVER PANAMA AND COLOMBIA. A SURFACE TROUGH EXTENDS FROM THE CENTRAL ATLC ACROSS THE LEEWARD ISLANDS NEAR 17N62W OVER HISPANIOLA TO NEAR 19N76W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 16N TO OVER THE GREATER ANTILLES AND THE VIRGIN ISLANDS BETWEEN 63W-76W WHILE THE REMAINDER OF THE CARIBBEAN REMAINS RATHER CLEAR THIS MORNING. ATLANTIC OCEAN... AN UPPER TROUGH EXTENDS OVER THE W ATLC N OF 26N W OF 63W ACROSS N FLORIDA AND GULF OF MEXICO WITH THE ASSOCIATED COLD FRONT JUST N OF THE REGION. A JET STREAM WITH WINDS ESTIMATED TO BE 80 TO 120 KT EXTENDING FROM THE N BAHAMAS NEAR 26N77W TO BEYOND 32N58W. BROAD UPPER RIDGE COVERING THE GULF OF MEXICO AND THE CARIBBEAN EXTENDS OVER THE W ATLC INTO THE CENTRAL ATLC W OF 55W WITH A SURFACE RIDGE COVERING THE W ATLC INTO THE GULF OF MEXICO W OF 65W. BROAD UPPER TROUGH COVERS THE REMAINDER OF THE ATLC N OF 20N E OF 45W WITH A REMNANT SURFACE TROUGH EXTENDING FROM 31N45W ALONG 23N48W INTO THE CARIBBEAN ACROSS THE LEEWARD ISLANDS NEAR 17N62W GENERATING SCATTERED CLUSTERS OF ISOLATED SHOWERS/THUNDERSTORMS FROM 21N-27N BETWEEN 41W AND THE SURFACE TROUGH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 21N BETWEEN THE VIRGIN ISLANDS NEAR 63W AND E CUBA NEAR 75W INCLUDING THE TURKS AND CAICOS. A WEAK 1016 MB HIGH IS LOCATED NE OF THE CAPE VERDE ISLANDS NEAR 20N31W. WESTERLY NEAR ZONAL UPPER LEVEL FLOW DOMINATES THE TROPICS ENHANCING THE ACTIVITY IN THE ITCZ SECTION ABOVE. $$ WALLACE