000 AXNT20 KNHC 091044 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON APR 09 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 1045 UTC. ...THE ITCZ... AXIS IS CENTERED ALONG 7N12W 4N20W 2N30W CROSSING THE EQ AT 40W AND CONTINUING INTO NE BRAZIL NEAR 2S48W. SCATTERED MODERATE IS WITHIN 120 NM N OF THE AXIS BETWEEN 19W-24W. ISOLATED MODERATE IS WITHIN 150 NM N OF AXIS W OF 32W. ...DISCUSSION... THE GULF OF MEXICO... A SWATH OF LOW AND MID LEVEL CLOUDS WITH EMBEDDED SCATTERED STRATIFORM PRECIP COVERS MUCH OF REGION N OF 26N. THIS IS ASSOCIATED WITH OVERRUNNING MOISTURE ALONG AND TO THE N OF A WARM FRONT THAT STRETCHES FROM 27N85W TO A 1014 MB LOW NEAR 26N95W. A DISSIPATING STATIONARY FRONT EXTENDS SWD FROM THE LOW TO 20N96W THEN CURVES BACK NWD BANKED AGAINST THE SLOPES OF THE SIERRA MADRE MOUNTAINS IN MEXICO. THIS FRONTAL SYSTEM HAS PRODUCED A FAIRLY DRAMATIC CONTRAST IN TEMPS RANGING FROM NEAR 50 F ACROSS THE GULF COAST TO THE LOW TO MID 70'S IN THE WARM SECTOR. IN ADDITION...THE INTERACTION BETWEEN THE SFC LOW AND HIGH PRES OVER ERN TEXAS HAS LED TO PERSISTENT STRONG NE WINDS AND WIND WAVES IN THE NW GULF...WHICH HAS PROMPTED A HIGH SURF ADVISORY FOR BEACHES ALONG S TX. SEE STATEMENTS FROM WFO BROWNSVILLE FOR MORE INFO. MAINLY FAIR CONDITIONS CONTINUE ACROSS THE SE GULF SUPPORTED BY SFC HIGH PRES CENTERED N OF THE BAHAMAS. IN THE MID AND UPPER LEVELS...THE FLOW IS ZONAL ACROSS THE NRN HALF AND WSW ACROSS THE SRN. THE WSW FLOW IS TRANSPORTING A STREAK OF CIRRUS SE OF A LINE FROM TAMPICO TO FT MYERS. IT DOES APPEAR THAT THE HIGH CLOUDS SHOULD THICKEN THRU THE DAY AS AN ABUNDANT FEED IS POURED INTO THE SW GULF. OVER THE NEXT COUPLE OF DAYS...NWP MODELS SHOW THE WEAK LOW AND FRONT LIFTING N AND BECOME INCREASINGLY ZONAL IN STRUCTURE. THIS WILL HELP TO DESTABILIZE MUCH OF THE GULF AS MOIST LOW-LEVEL SLY FLOW DEVELOPS TARGETING SHOWERS AND TSTMS ACROSS THE N CENTRAL AND NE GULF. THE CARIBBEAN SEA... A BROAD MID TO UPPER LEVEL RIDGE COVERS THE REGION ANCHORED BY AN UPPER HIGH CENTERED NEAR THE ABC ISLANDS. SLY FLOW ON THE W SIDE OF THE UPPER ANTICYCLONE AS WELL AS LOW-LEVEL CONVERGING FLOW ALONG THE ITCZ AXIS IS FUELING PATCHES OF MODERATE TO STRONG CONVECTION OVER COLOMBIA. LEFT OVER HIGH CLOUDS ARE BEING PUSHED NWD INTO THE S CARIB W OF 70W BY THE SLY FLOW. IN THE LOWER LEVELS...LIGHT TO MODERATE TRADES DOMINATE AS THE GRADIENT IS STILL FAIRLY LOOSE IN RESPONSE TO THE RECENT FRONTAL BOUNDARY THAT IS NOW MOSTLY N OF THE AREA. HOWEVER...A BROKEN DECK OF LOW-MID LEVEL CLOUDS AND LIKELY SCATTERED SHOWERS LIE OVER THE ISLAND OF HISPANIOLA ASSOCIATED WITH THE FRONT'S REMNANT MOISTURE AND LOCAL TOPO AND ONSHORE FLOW INFLUENCES. LOOKING AHEAD A COUPLE OF DAYS...THE TRADES MAY INCREASE SLIGHTLY AS THE FRONT DISSIPATES AND A NARROW WEAK SFC RIDGE BUILDS N OF THE AREA. THE ATLANTIC OCEAN... WEAK SFC HIGH PRES...ANALYZED 1022 MB N OF THE CENTRAL BAHAMAS NEAR 27N73W...IS BUILDING E ACROSS THE WRN ATLC BEHIND A STATIONARY FRONT THAT ENTERS THE AREA NEAR 32N51W AND CONTINUES SW TO THE N SHORE OF HISPANIOLA NEAR 20N70W. BROKEN TO OVERCAST MULTILAYERED CLOUDS WITH EMBEDDED SCATTERED SHOWERS ARE WITHIN 150 NM EITHER SIDE OF THE FRONT. THERE IS NOT MUCH UPPER SUPPORT FOR THIS SFC FEATURE...WITH THE FLOW BEING MAINLY SWLY IN THE SW ATLC. MOST OF THE DYNAMICS/UPPER ENERGY IS LOCATED WELL N OF THE REGION AND FOR THAT REASON...THE BOUNDARY WILL GRADUALLY DISSIPATE THROUGH MID-WEEK WITH A WEAK E-W SFC RIDGE TAKING ITS PLACE. THE MID AND UPPER LEVEL PATTERN IN THE CENTRAL AND ERN ATLC IS HIGHLY AMPLIFIED WITH A STRONGLY TITLED RIDGE AXIS STRETCHING NEWD FROM THE E CARIB ALONG 20N60W 32N48W. AN ASSOCIATED 1024 MB SFC HIGH PRES SYSTEM IS LOCATED NEAR 30N41W CONTROLLING MUCH OF THE SFC PATTERN AND PRODUCING MODERATE TRADES S OF 15N BETWEEN 30W-50W. THE UPPER FLOW THEN FOLDS INTO A BROAD EXTENSIVE TROUGH WITH A ROUGH AXIS RUNNING FROM AN UPPER LOW NEAR THE MADEIRA ISLANDS WELL SSW INTO THE DEEP TROPICS NEAR 4N40W. THIS UPPER TROUGH HAS A SERIES OF WEAK SFC LOWS WHICH CONSIST OF A 1011 MB NEAR 30N20W...A 1012 MB NEAR 35N16W AND ANOTHER 1012 MB NEAR 33N24W. BESIDES FOR SCATTERED SHOWERS WITHIN 120 NM IN THE NE SEMICIRCLES OF THE LOWS AND A PATCH OF MAINLY HIGH CLOUDS FROM 15N-23N BETWEEN 26W-32W...FAIR TO MOSTLY CLEAR SKIES ARE THE RULE. $$ CANGIALOSI