000 AXNT20 KNHC 171116 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST FRI MAR 17 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...WEATHER OBSERVATIONS... RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 6N10W 4N17W 4N30W 4N46W 2N51W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS S OF 5N ACROSS THE EQUATOR BETWEEN 10W-14W AND FROM 1N TO INLAND OVER SW AFRICA FROM THE PRIME MERIDIAN TO 3W. CLUSTERS OF SIMILAR CONVECTION ARE FROM 3N TO JUST S OF THE EQUATOR BETWEEN 3W-7W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 2N-7N BETWEEN 43W-54W. ...DISCUSSION... GULF OF MEXICO... DEEP LAYERED TROUGH CONTINUES TO APPROACH THE NW GULF REMAINING MAINLY OVER THE CENTRAL PLAIN STATES WITH ASSOCIATED COLD FRONT STILL INLAND OVER LOUISIANA/TEXAS. WEAK 1021 MB SURFACE HIGH IS OVER SW GEORGIA. THE GULF IS UNDER UPPER WESTERLY ZONAL FLOW IN RESPONSE TO AN UPPER RIDGE IN THE W ATLC. WEAK COLD FRONT WILL ENTER THE GULF LATER TODAY CLIPPING THE N GULF AND WILL EXIT THE GULF LATE IN THE DAY ON SAT. A SECOND SURFACE RIDGE WILL MOVE S FROM OVER THE US INTO THE GULF SAT FOR THE REMAINDER OF THE WEEKEND SHIFTING EASTWARD INTO THE W ATLC BY SUN NIGHT. CARIBBEAN SEA... UPPER SW FLOW DOMINATES THE W CARIBBEAN W OF 72W WITH UPPER WESTERLY ZONAL FLOW OVER THE EAST. STRONG SUBSIDENCE AND DRY UPPER AIR CONTINUES TO HAVE A FIRM HOLD OF THE ENTIRE AREA. ALTHOUGH TROPICAL MOISTURE IS BEING ADVECTED FROM OVER SOUTH AMERICA GENERATING SCATTERED SHOWERS INLAND OVER COLOMBIA BUT NOT MAKING IT INTO THE CARIBBEAN. AFRICAN DUST CONTINUES TO THIN DUE TO THE MODERATE/STRONG EASTERLY TRADE WINDS WITH ONLY ARUBA REPORTING HAZY CONDITIONS. LITTLE CHANGE IS EXPECTED FOR THE AREA DURING THE WEEKEND. ATLANTIC OCEAN... BROAD UPPER RIDGE CONTROLS THE W ATLC WITH THE AXIS EXTENDING FROM CENTRAL CUBA NE TO 31N67W. AT THE SURFACE...A WEAKENING 1023 MB HIGH IS LOCATED NEAR 28N71W COVERING THE W ATLC W OF THE CENTRAL ATLC FRONTAL BOUNDARY. DEEP LAYERED TROUGH IS IN THE CENTRAL ATLC N OF 19N FROM 43W-60W WITH THE ASSOCIATED COLD FRONT EXTENDING INTO THE AREA NEAR 32N46W TO 25N58W WHERE IT BECOMES STATIONARY TO THE TURKS AND CAICOS NEAR 22N71W. SCATTERED SHOWERS ARE WITHIN 60 NM E OF THE FRONT N OF 26N. UPPER RIDGE COVERS THE E/CENTRAL ATLC EXTENDING FROM NEAR 19N38W N TO BEYOND 32N34W. AT THE SURFACE...A 1021 MB HIGH IS LOCATED NEAR 26N46W WITH A WEAKENING RIDGE COVERING THE THE ATLC E OF THE FRONT TO 30W. A VERY WELL DEFINED DEEP LAYERED LOW...AND THE ASSOCIATED SURFACE LOW REMAINS N OF THE REGION WITH THE UPPER TROUGH EXTENDING THROUGH 32N17W TO 20N21W. ASSOCIATED SURFACE TROUGH EXTENDS FROM 32N14W JUST W OF THE CANARY ISLANDS TO 26N24W. THE DENSE AFRICAN DUST REMAINS OVER E ATLC ALTHOUGH IT IS NOT AS IMPRESSIVE AS IT HAS BEEN OVER THE PAST FEW DAYS. THINNING DUST COVERS THE AREA N OF THE ITCZ AND S OF A LINE FROM THE AFRICAN COAST NEAR 22N17W TO 16N51W. BROAD UPPER RIDGE EXTENDS ACROSS THE TROPICAL ATLC FROM AFRICA NEAR 6N10W ALONG 7N30W TO OVER SOUTH AMERICA NEAR 9N60W ENHANCING CONVECTION WITHIN THE ITCZ ESPECIALLY OFF THE AFRICAN COAST. OTHERWISE... GENERALLY TRANQUIL WEATHER PREVAILS OVER THE MOST OF THE ATLC. $$ WALLACE