000 AXNT20 KNHC 031726 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST SAT MAR 03 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 7N10W 3N23W 2N34W CROSSING THE EQUATOR AT 41W INTO NE SOUTH AMERICA NEAR 1S48W. CLUSTERS SCATTERED MODERATE CONVECTION ARE S OF 4N W OF 30W TO INLAND OVER SOUTH AMERICA. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER TROUGH COVERS THE E US INTO THE W ATLC AND OVER THE N GULF N OF 26N WITH THE ASSOCIATED COLD FRONT EXTENDING THROUGH THE W ATLC OVER FLORIDA JUST N OF LAKE OKEECHOBEE TO A WEAKENING 1009 MB LOW NEAR 26N96W CONTINUING S AS A STATIONARY FRONT TO THE E BAY OF CAMPECHE. THE STATIONARY PORTION IS BEGINNING TO MOVE NW AS A WARM FRONT. A SECONDARY PUSH OF DRIER AIR EXTENDS FROM GEORGIA ACROSS THE FLORIDA PANHANDLE ALONG 30N87W TO TEXAS NEAR CORPUS CHRISTI...BUT IS ALREADY LOSING ITS IDENTITY. DENSE CLOUDS WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE OVER THE NE GULF WITHIN 60/75 NM OF LINE FROM 26N88W TO OVER FLORIDA NEAR TAMPA. ZONAL UPPER WESTERLY FLOW DOMINATES THE REMAINDER OF THE GULF. CARIBBEAN... MID/UPPER LEVEL HIGH IS CENTERED OVER THE NW CARIBBEAN NEAR 18N84W WITH THE RIDGE AXIS EXTENDING NE ACROSS CUBA NEAR 21N79W INTO THE W ATLC. THIS FEATURE ENCOMPASSES THE ENTIRE CARIBBEAN. STRONG SUBSIDENCE AND VERY DRY AIR ALSO DOMINATE THE ENTIRE REGION. PRESSURE GRADIENT BETWEEN THE SURFACE RIDGE OVER THE ATLC AND THE LOW PRESSURE OVER THE TROPICS INTO THE E PACIFIC REGION IS GENERATING STRONG EASTERLY TRADE WINDS ACROSS THE AREA POSSIBLY USHERING IN SOME ISOLATED LOW LEVEL SHOWERS ACROSS THE REGION. ATLANTIC... BROAD UPPER TROUGH THAT EXTENDS FROM OVER THE E US INTO W ATLC IS N OF 28N W OF 75W WITH THE ASSOCIATED COLD FRONT EXTENDING INTO THE REGION NEAR 32N74W SW ACROSS FLORIDA JUST N OF LAKE OKEECHOBEE. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 75/90 NM OF LINE FROM ACROSS FLORIDA NEAR DAYTONA BEACH TO BEYOND 32N75W. BROAD UPPER RIDGE EXTENDS FROM THE CARIBBEAN ACROSS CUBA NEAR 21N79W INTO THE W AND CENTRAL ATLC TO BEYOND 32N58W COVERING THE AREA W OF 55W. STRONG SUBSIDENCE AND VERY DRY UPPER AIR ALSO DOMINATE THE ENTIRE REGION S OF 30N W OF 45W LIMITING SHOWERS ACTIVITY E OF THE W ATLC/GULF COLD FRONT. A SURFACE RIDGE EXTENDS FROM A 1030 MB HIGH WELL N OF THE REGION THROUGH 32N54W SW TO 25N71W. MID/UPPER TROUGH EXTENDS THROUGH 32N35W SW ALONG 25N47W TO 17N51W WITH THE ASSOCIATED COLD FRONT DIPPING INTO THE REGION THROUGH 32N32W TO 29N40W. A RE-ENFORCING SURGE OF COLD AIR IS JUST N OF THE REGION. A WEAK SURFACE TROUGH IS IN THE W TROPICAL ATLC JUST TO THE SW OF THE UPPER TROUGH EXTENDING FROM 22N54W TO 12N57W. A WEAKENING UPPER LOW IS OVER THE CANARY ISLANDS WITH A MID/UPPER TROUGH EXTENDING S TO OVER THE CAPE VERDE ISLANDS WITH MODERATE/STRONG SUBSIDENCE AND DRY AIR WITHIN 300/350 NM OF THE UPPER TROUGH AXIS. AN UPPER RIDGE IS OVER THE E TROPICAL ATLC WITH THE APEX NEAR 21N35W AND BEGINNING TO OVERRUN TO MID/UPPER TROUGH OVER THE FAR E ATLC. $$ WALLACE