000 AXNT20 KNHC 062346 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST FRI MAR 06 2009 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND 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 1800 UTC SURFACE ANALYSIS...AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 5N8W 2N20W CROSSING THE EQUATOR NEAR 29W EXTENDING TO 2S35W INTO NE BRAZIL NEAR 4S44W. ISOLATED MODERATE CONVECTION IS ALONG THE ITCZ AXIS BETWEEN 12W-20W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS OVER PARTS OF LIBERIA...AND WHERE THE ITCZ MEETS NE BRAZIL. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL RIDGE CONTINUES TO DOMINATE MUCH OF THE GULF REGION AND THE SE CONUS. MODERATE TO STRONG UPPER-LEVEL SUBSIDENCE AND IMPLIED DRY AIR MASS IS NOTED WITHIN THE RIDGE. AS A RESULT...GENERALLY FAIR WEATHER CONDITIONS PERSIST ACROSS THE GULF WATERS. THE SUBSIDENCE IS BEING SUPPORTED BY A SURFACE RIDGE THAT EXTENDS SOUTHWESTWARD FROM A 1034 MB SURFACE HIGH IN THE W ATLC NEAR 32N72W. THE FLOW AROUND THIS SURFACE RIDGE IS RESULTING IN MAINLY SE WINDS OF 15-20 KT ACROSS MUCH OF THE GULF. ELY WINDS OF 20-25 KT CONTINUE BLOWING THROUGH THE STRAITS OF FLORIDA AND ACROSS THE SE PORTION OF THE GULF S OF 24N. THE SFC HIGH IS EXPECTED TO MOVE SLIGHTLY SW AND REMAIN NEARLY STATIONARY DURING THE UPCOMING WEEKEND. AS A RESULT...THE OVERALL WEATHER PATTERN ACROSS THE GULF WILL CHANGE LITTLE THROUGH SUN NIGHT. CARIBBEAN SEA... THE TAIL END OF A COLD FRONT OVER THE CENTRAL ATLANTIC OCEAN REACHES THE N LEEWARD ISLANDS GENERATING SOME CLOUDINESS AND LIGHT TO MODERATE SHOWERS. THE FRONTAL BOUNDARY HAS BECOME ILL DEFINED ACROSS THE EASTERN CARIBBEAN WITH SATELLITE IMAGERY INDICATING A BAND OF MAINLY LOW-LEVEL CLOUDS ASSOCIATED WITH THE REMNANTS OF THIS FRONT WHICH EXTENDS FROM THE N LEEWARD ISLANDS TO THE ABC ISLANDS WHERE SOME SHOWER ACTIVITY IS OBSERVED. NE-E LOW LEVEL WINDS ASSOCIATED WITH THE SFC HIGH IN THE W ATLC ARE TRANSPORTING PATCHES OF SHALLOW MOISTURE ACROSS CUBA AND HISPANIOLA. FRESH TO STRONG NE-E WINDS ARE BLOWING ACROSS THE MAJORITY OF THE BASIN ADVECTING POCKETS OF LOW LEVEL MOISTURE WITH EMBEDDED SHOWERS ACROSS THE CARIBBEAN WATERS INTO CENTRAL AMERICA. THE GREATEST CONCENTRATION OF THESE SHOWERS IS SOUTH OF JAMAICA FROM 14N-17N BETWEEN 74W-79W. ALSO...A GALE WARNING IS IN EFFECT FOR LOCATIONS WITHIN 90 NM OF THE COLOMBIAN COAST WITH THE INCREASED SURFACE WINDS RESULTING FROM THE INCREASED SURFACE PRESSURE GRADIENT ACROSS THE CARIBBEAN. ALOFT... SUBSIDENCE RESULTING FROM CONFLUENCE IN WESTERLY FLOW ALOFT IS LIMITING DEEP CONVECTION ACROSS MUCH OF THE REGION. ATLANTIC OCEAN... A DEEP LAYERED TROUGH REMAINS OVER THE W ATLC. THE ASSOCIATED COLD FRONT EXTENDS FROM A DEVELOPING GALE CENTER NEAR 30N51W TO THE N LEEWARD ISLANDS. LOW LEVEL CONVERGENCE IS HELPING TO INDUCE SCATTERED SHOWERS WITHIN 70 NM EITHER SIDE OF THIS FRONT...AND IS ALSO SUPPORTING SCATTERED SHOWERS WITHIN 80 NM EITHER SIDE OF A PRE-FRONTAL TROUGH WHICH LIES ALONG 13N55W 19N53W 24N53W. ALL THIS ACTIVITY IS BEING SUPPORTED BY UPPER LEVEL DIVERGENCE ASSOCIATED WITH TWO UPPER LEVEL JET MAXIMA IN THE VICINITY OF THE SURFACE LOW. THE SURFACE LOW IS FORECAST TO MOVE NORTHEASTWARD DURING THE NEXT DAY. IN THE WAKE OF THE FRONT...A RELATIVELY COOLER AND DRIER AIRMASS IS PRESENT ASSOCIATED WITH A 1034 MB HIGH LOCATED NEAR 32N72W. BROKEN COLD AIR STRATOCUMULUS CLOUDS ARE NOTED MOVING ACROSS THE W ATLC INTO THE BAHAMAS AND CUBA UNDER A PREVAILING NE-E FLOW. ACROSS THE E ATLC...AN UPPER LOW IS LOCATED NEAR 27N24W. ATMOSPHERIC INSTABILITY ASSOCIATED WITH THIS UPPER LOW IS SUPPORTING SCATTERED SHOWERS FROM 27N-31N BETWEEN 20W-27W. HOWEVER... SUBSIDENCE ASSOCIATED WITH A SURFACE RIDGE IS INHIBITING DEEP CONVECTION ACROSS MUCH OF THE E ATLC. MID/UPPER LEVEL MOISTURE IS BEING DRAWN ACROSS THE EASTERN ATLC BETWEEN THE CANARY AND THE CAPE VERDE ISLANDS BY STRONG SWLY WINDS ALOFT. AN UPPER-LEVEL RIDGE LOCATED NEAR 4N34W DOMINATES MUCH OF THE DEEP TROPICS. $$ GR