000 AXNT20 KNHC 121017 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON MAR 12 2007 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0945 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 10N12W 4N23W 1N36W THEN ALONG THE EQUATOR FROM 44W-52W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 120/150 NM OF THE AXIS FROM 21W-37W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 150 NM OF THE AXIS FROM 37W-46W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE REMAINS OVER THE GULF WITH THE AXIS EXTENDING FROM THE CARIBBEAN OVER W CUBA TO THE NORTH-CENTRAL GULF COAST. THIS CONTINUES TO ADVECT UPPER LEVEL MOISTURE ACROSS MEXICO AND THE W GULF. THE DEEP LAYERED LOW/TROUGH AND THE ASSOCIATED SURFACE FRONTAL BOUNDARY REMAIN INLAND OVER TEXAS AND IS NOT EXPECTED TO MAKE IT INTO THE GULF BUT OVER THE NEXT 24 TO 36 HOURS WILL MOVE EASTWARD OVER THE N GULF COAST STATES. HOWEVER...A SQUALL LINE WELL AHEAD OF THE FRONT IS MOVING INTO THE GULF WATERS ALONG THE COAST OF TEXAS FROM CORPUS CHRISTI TO GALVESTON AT 0930 UTC. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS DOT THE AREA N OF 26N W OF 93W. A FRONTAL BOUNDARY REMAINS IN THE NW ATLC JUST N OF THE REGION WITH A SURFACE RIDGE OVERRUNNING THE FRONT OVER THE GULF OF MEXICO TO THE NW CARIBBEAN AND INTO THE W ATLC. MODERATE/STRONG EASTERLY SURFACE WINDS ARE BANKING LOW LEVEL CLOUDS ALONG THE COAST OF TEXAS ENHANCING THE SHOWERS AND THUNDERSTORMS THERE. OTHER THAN PATCHES OF HIGH CLOUDS THE REMAINDER OF THE GULF REMAINS CLOUD AND SHOWER FREE. CARIBBEAN... BROAD UPPER RIDGE COVERS THE ENTIRE CARIBBEAN EXTENDING FROM OVER VENEZUELA ACROSS W CUBA INTO THE GULF OF MEXICO. MODERATE/STRONG SUBSIDENCE AND VERY DRY AIR AT ALL LEVELS ARE LEAVING THE CARIBBEAN MOSTLY CLOUD FREE WITH VIRTUALLY NO SHOWERS. THE EXCEPTION IS FROM OVER HISPANIOLA TO PUERTO RICO AND THE IMMEDIATE COASTAL WATERS WHERE A REMNANT FRONTAL BOUNDARY OVER THE W ATLC EXTENDS A SURFACE TROUGH TO THE MONA PASSAGE GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS. THIS SURFACE TROUGH AND ASSOCIATED WEATHER WILL MOVER ACROSS PUERTO RICO LATER TODAY. MODERATE/STRONG EASTERLY TRADE WINDS CONTINUE ACROSS THE ENTIRE CARIBBEAN AND WILL REMAIN THROUGH THE FIRST OF THE WEEK. ATLANTIC... DEEP LAYERED TROUGH COVERS THE W ATLC FROM 55W-80W WITH THE ASSOCIATED COLD FRONT EXTENDING INTO THE AREA ALONG 32N59W TO 26N61W THEN CONTINUING AS A SURFACE TROUGH TO THE MONA PASSAGE. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE N OF 27N FROM 53W-60W WITH BROKEN/OVERCAST LOW CLOUDS WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 45 NM OF THE SURFACE TROUGH. MODERATE/STRONG SUBSIDENCE AND VERY DRY AIR AT ALL LEVELS IS LEAVING THE REMAINDER OF THE W ATLC MOSTLY CLOUD AND SHOWER FREE. A DEEP LAYERED TROUGH OVER THE NE ATLC EXTENDS INTO THE REGION N OF 27N FROM 17W-35W WITH THE ASSOCIATED COLD FRONT N OF THE AREA. BROAD SURFACE RIDGE COVERS THE CENTRAL AND E ATLC N OF 15N E OF 60W ANCHORED BY A 1038 MB HIGH WNW OF THE AZORES. THE REMAINDER OF THE ATLC IS UNDER RATHER BENIGN UPPER LEVEL FEATURES AS WELL AS MODERATE/STRONG SUBSIDENCE AND VERY DRY AIR AT ALL LEVELS. ALL THIS IS KEEPING THE REMAINDER OF THE ATLC QUIET THIS MORNING. $$ WALLACE