000 AXNT20 KNHC 202317 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT THU APR 20 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 6N10W 4N20W 2N30W EQ36W 2S43W. NUMEROUS SHOWERS AND TSTMS ARE E OF 20W FROM THE EQ TO 12N. THE STRONGEST TSTMS ARE INLAND OVER W AFRICA. SCATTERED SHOWERS WITH EMBEDDED ISOLATED TSTMS ARE WITHIN 250 NM TO THE N OF THE AXIS W OF 30W. CLUSTERS OF MODERATE CONVECTION IS INLAND OVER S AMERICA SPREADING NWD INTO THE ATLC S OF 2N W OF 43W. ...DISCUSSION... GULF OF MEXICO... SLIGHT MID-UPPER RIDGING IS OVER THE GULF OF MEXICO WITH WIDESPREAD MODERATE DRY/STABLE AIR ALOFT ACROSS THE AREA. DEEP MOISTURE LIES TO THE N OF THE REGION WITH A WIDE SHIELD OF RAIN AND BANDS OF STRONG STORMS OVER TEXAS AND PARTS OF THE SE U.S. A 1016 MB HIGH IS CENTERED S OF THE FL PANHANDLE NEAR 29N85W. FAIR TO MOSTLY CLEAR SKIES PREVAIL ACROSS THE GULF. W OF THE 1016 MB HIGH...SFC WINDS ARE GENERALLY SELY NEAR 15-20 KT WITH SOME PATCHES OF LOW-MID LEVEL CLOUDS W OF 95W. THIS MOISTURE THEN SPREADS NWD INTO THE DEEP MOISTURE OVER TEXAS. A FEW TSTMS HAVE DEVELOPED OVER S AND CNTRL FL ASSOCIATED WITH SEA BREEZE CONVERGENCE. HIGH PRESSURE WILL BUILD E OF FL TOMORROW KEEPING WARM RETURN SFC FLOW IN THE GULF. GFS SUGGESTS THAT A NEW HIGH CENTER WILL FORM OVER ALONG THE N GULF COAST SAT ALLOWING FAIR WEATHER TO CONTINUE OVER THE NEXT FEW DAYS. UNSETTLED WEATHER WILL REMAIN TO THE N OF THE AREA ACROSS THE SE U.S. TOMORROW. CARIBBEAN SEA... AN UPPER HIGH IS CENTERED OFF THE W COAST OF NICARAGUA NEAR 11N88W. A DEEP-LAYER TROUGH LIES TO THE N OF THE AREA ACROSS THE W ATLC. IN THE CARIBBEAN...UPPER LEVEL ZONAL WESTERLY WINDS EXIST BETWEEN THESE FEATURES. PLENTY OF MODERATE SUBSIDENCE LIES ABOVE THIS AREA WITH A ZONE OF ENHANCED SUBSIDENCE DUE TO UPPER LEVEL CONFLUENCE FROM 16N-20N BETWEEN 69W-85W. CLUSTERS OF MODERATE TO STRONG CONVECTION HAS FIRED THIS AFTERNOON OVER COLUMBIA...PANAMA AND COSTA RICA DUE TO SFC HEATING AND UPPER LEVEL DIVERGENCE TO THE E OF THE UPPER HIGH. MODERATE TRADES ARE BLOWING ACROSS THE CARIBBEAN WITH PATCHES OF LOW LEVEL CLOUDS WITH EMBEDDED SHOWERS SCATTERED ACROSS THE SEA. THE THICKEST AREA OF TRADE WIND SHOWERS IS S OF JAMAICA FROM 15N-17N BETWEEN 76W-81W. FAIR WEATHER IS EXPECTED TO CONTINUE ACROSS THIS AREA THRU SAT. TRADE WINDS ARE LIKELY TO INCREASE IN MAGNITUDE AS SFC HIGH PRESSURE BECOMES MORE ESTABLISHED TO THE N OF THE AREA THIS WEEKEND. ATLANTIC OCEAN W OF 40W... A DEEP-LAYERED LOW IS LOCATED SE OF NOVA SCOTIA NEAR 40N60W. THIS LOW HAS CARVED OUT A DEEP TROUGH ACROSS THE AREA. THE UPPER AXIS EXTENDS FROM THE UPPER LOW SWD ALONG 32N65W 20N68W. A WEAK AREA OF LOW PRESSURE N OF THE BAHAMAS HAS FIZZLED TO A ILL-DEFINED SFC TROUGH FROM 30N77W TO 26N75W. A PATCH OF CLOUDS AND A FEW SHOWERS ARE DISSIPATING NEAR THIS FEATURE. A DISSIPATING COLD FRONT ENTERS THE AREA ALONG 32N51W 26N56W 22N63W THEN AS A DISSIPATING STATIONARY FRONT TO 22N68W. BROKEN CLOUDS AND SCATTERED SHOWERS ARE WITHIN 100 NM OF THE FRONT. DEEPER MOISTURE LIES A FEW HUNDRED MILES TO THE E OF THE FRONT FROM 20N TO BEYOND 32N BETWEEN 43W-51W. THIS MOISTURE LIES ON THE FAVORABLE E SIDE OF THE TROUGH WHERE UPPER LEVEL DIFFLUENCE IS THE STRONGEST. THE DEEP-LAYER LOW WILL PULL ENEWD ALLOWING MORE OF A ZONAL UPPER LEVEL PATTERN TO DEVELOP ON SAT. SFC HIGH PRESSURE WILL BECOME MORE ESTABLISHED IN THE W ATLC THIS WEEKEND. EAST ATLANTIC... A 1029 MB HIGH CENTERED NEAR 35N32W DOMINATES THE E ATLC. SCATTERED STRATOCUMULUS CLOUDS ARE LOCATED TO THE E OF THE HIGH CENTER. IN THE UPPER LEVELS...A NARROW AMPLIFIED RIDGE EXTENDS FROM 20N45W TO 32N38W WITH UPPER TROUGHING E OF 25W N OF 25N. SAHARAN DUST HAS BLOWN IN THE E ATLC E OF 25W FROM 10N-20N. $$ CANGIALOSI