000 AXNT20 KNHC 090546 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST SAT FEB 09 2008 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0530 UTC. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 5N9W 2N20W 2N40W THEN INLAND OVER SOUTH AMERICA NEAR EQ50W. SCATTERED STRONG CONVECTION IS FROM 2N TO THE COAST OF LIBERIA. ANOTHER AREA OF SCATTERED STRONG CONVECTION IS FROM THE EQUATOR TO 5N BETWEEN 16W-20W. SMALL CLUSTERS OF SCATTERED MODERATE CONVECTION ARE NOTED ELSEWHERE WITHIN 120 NM OF THE AXIS BETWEEN 20W-30W AND BETWEEN 35W-42W. ...DISCUSSION... GULF OF MEXICO... RESIDUAL EFFECTS OF AN UPPER LEVEL SHEARED TROUGH EXITING THE ERN U.S. AND OVER THE N-CENTRAL ATLC ARE CONFINED TO THE FAR SE PORTION OF THE GULF OF MEXICO. THIS IS PROVIDING LIMITED SUPPORT FOR A STATIONARY FRONT EXTENDING FROM 31N72W SOUTHWESTWARD ACROSS THE FLORIDA PENINSULA NEAR LAKE OKEECHOBEE THEN CONTINUING ALONG 24N87W AND DISSIPATING FROM THERE INTO THE BAY OF CAMPECHE NEAR 21N94W. WIDELY SCATTERED SHOWERS ARE OCCURRING JUST OFF THE FLORIDA E COAST WITHIN 60 NM EITHER SIDE OF THE FRONT. PATCHES OF BROKEN LOW CLOUDS COMPRISE THE BULK OF THE FRONT OVER THE GULF OF MEXICO. ANOTHER UPPER LEVEL SHORTWAVE TROUGH IS MOVING ACROSS THE MISSOURI RIVER VALLEY AND EXTENDS SOUTHWARD INTO ERN TEXAS AND WILL MOVE ACROSS THE SE CONUS OVER THE WEEKEND. A BROAD AREA OF SWLY UPPER LEVEL WINDS ARE NOTED OVER THE ENTIRE GULF BETWEEN THE TROUGH AND AN UPPER RIDGE IN THE CARIBBEAN EXTENDING NEWD INTO THE W ATLC. STRONG SW WINDS ALOFT WERE ADVECTING SOME HIGH LEVEL MOISTURE ACROSS THE GULF STATES. THE STATIONARY FRONT IS EXPECTED TO DISSIPATE LATER TODAY. HIGH PRESSURE WILL BUILD ACROSS GULF THROUGH TONIGHT AND STRENGTHEN SUN/MON THEN MOVE E OF THE AREA TUE. CARIBBEAN SEA... A PERSISTENT UPPER LEVEL RIDGE EXTENDS FROM THE SW CARIBBEAN ALONG 80W NEWD ACROSS EASTERN CUBA...THE BAHAMAS AND NE ACROSS THE SUBTROPICAL ATLC. A SHEARED UPPER TROUGH AXIS EXTENDS WSWWD ACROSS THE TROPICAL ATLC ACROSS THE NORTHEAST WINDWARD ISLANDS TO A DIFFUSE CYCLONIC CIRCULATION JUST S OF HISPANIOLA AND THE MONA PASSAGE. THE SURFACE RIDGE OVER THE ATLC COUPLED WITH THE LOWER PRESSURE OVER SOUTH AMERICA IS PRODUCING A RATHER TIGHT PRESSURE GRADIENT OVER THE CARIBBEAN AND IS GENERATING MODERATE TO STRONG EASTERLY TRADE WINDS ACROSS THE AREA. THE EDGE OF THIS EVENINGS QUIKSCAT PASS INDICATED 25 KT WINDS ALONG THE COAST OF COLOMBIA/VENEZUELA. MODERATE/STRONG SUBSIDENCE AND DRY AIR UPPER AIR ARE LIMITING ANY AREAS OF DEEP CONVECTION ACROSS THE AREA. HOWEVER...THE STRONG TRADE WINDS ARE USHERING IN SOME LOW LEVEL CLOUDS WITH SOME LOW LEVEL CONVERGENCE MANIFESTING ITSELF IN A PATCH OF SCATTERED SHOWERS IN THE VICINITY OF THE CAYMAN ISLANDS. ATLANTIC OCEAN... THE SHEARED UPPER LEVEL TROUGH OVER THE NE US AND N-CENTRAL ATLC HAS VIRTUALLY DISAPPEARED IN THE WAKE OF AN EXPANSIVE RIDGE COVERING A MAJORITY OF THE ATLC. THE ONLY MANIFESTATION OF THE SHEARED TROUGH IS A STATIONARY FRONT EXTENDING FROM 31N72W TO THE FLORIDA E COAST NEAR STUART. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 60 NM OF THE FRONT JUST OFF THE FLORIDA COAST. THE FRONT WILL WEAKEN THE DAY TODAY AS A SECOND COLD FRONT IS FORECAST TO MOVE OFF THE SE US COAST TONIGHT. STRONG HIGH PRESSURE WILL BUILD SE ACROSS THE W ATLC BEHIND THE SECOND FRONT THROUGH TUE INCREASING WINDS OVER THE AREA. THE EXPANSIVE RIDGE NOTED ABOVE DOMINATES THE CENTRAL ATLC BETWEEN 35W AND 75W. AN UPPER LEVEL ANTICYCLONE WAS NOTED NEAR 27N55W WITH THE SURFACE RIDGE ANCHORED BY A 1025 MB HIGH NEAR 28N50W. UPPER LEVEL LOW OVER THE NE ATLC NEAR THE CANARY ISLANDS/28N18W IS MOVING E 15 KT. STRONGLY POSITIVE TILT TROUGH EXTENDS FROM THE LOW WSWWD ACROSS 22N30W 18N40W THEN TRANSITIONS TO A SHEAR AXIS WHICH UNDERCUTS THE STRONG ATLC RIDGE ALONG 19N50W TO THE NE WINDWARD ISLANDS. AN ASSOCIATED SURFACE TROUGH EXTENDS FROM A 1009 MB LOW NEAR 28N21W JUST W OF THE WESTERNMOST CANARY ISLANDS TO 22N20W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE NOTED OVER THE CANARY ISLANDS FROM 27N-30N BETWEEN 16W-20W. AN E/W UPPER RIDGE EXTENDS ACROSS THE TROPICAL ATLC ALONG 5N TO 35W. A STRONG UPPER LEVEL JETSTREAM WITH WINDS OF 90-140 KT CUTS ALONG THE N PERIPHERY OF THE RIDGE WITHIN 120 NM OF LINE FROM 15N35W TO INLAND OVER W AFRICA/MAURITANIA NEAR 20N16W. $$ COBB