000 AXNT20 KNHC 042348 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED APR 4 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 8N10W 1N20W ALONG THE EQUATOR FROM 24W-42W AND INTO SOUTH AMERICA NEAR 2S48W. SCATTERED MODERATE CONVECTION IS WITHIN 100 NM OF THE AXIS FROM 18W-24W. CLUSTERS OF MODERATE TO STRONG CONVECTION ARE ALONG 7W FROM 3S TO 2N. ...DISCUSSION... GULF OF MEXICO... A MID/UPPER LEVEL RIDGE DOMINATES THE GULF...WITH THE AXIS EXTENDING NORTH FROM WRN CUBA THROUGH THE SE US. A SHORT WAVE TROUGH CONTINUES TO SLOWLY MOVE EWD ACROSS TEXAS AND MEXICO AND WILL BE ABSORBED BY A LONG WAVE TROUGH OVER THE CENTRAL PLAINS. IT AXIS LIES ALONG 100W AND IS STILL ENHANCING THE SHOWER/TSTM ACTIVITY OVER E MEXICO AND PARTS OF TEXAS AND LOUISIANA. THE MOSAIC DOPPLER RADAR FROM THE SE US SHOWS A BAND OF SHOWERS WITH EMBEDDED TSTMS OVER THE NW CORNER OF THE GULF N OF 27N BETWEEN 91W-97W WHERE THERE IS A WEAK SFC LOW. ASSOCIATED WITH THE UPPER TROUGH IS A FRONTAL BOUNDARY. AS OF 2100Z...THE FRONTAL SYSTEM EXTENDS FROM THE FLORIDA PANHANDLE TO A WEAK 1015 MB SFC LOW LOCATED NEAR 28N93W ENTERING THE DEEP SOUTH BETWEEN CORPUS CHRISTI AND BROWNSVILLE CONTINUING OVER NORTHERN MEXICO AS A STATIONARY FRONT. A WEAK SURFACE RIDGE EXTENDS FROM THE W ATLC ACROSS THE GULF ANCHORED BY A HIGH JUST NE OF THE BAHAMAS. THE COLD FRONT WILL MOVE SE ACROSS THE GULF REACHING SOUTH FLORIDA TOMORROW AFTERNOON. STRONG HIGH PRES WILL FOLLOW THE FRONT BRINGING AN INCREASE IN WINDS AND SEAS ACROSS THE AREA. CARIBBEAN SEA... A BROAD UPPER E/W RIDGE EXTENDS ACROSS THE N PORTION OF SOUTH AMERICA INTO THE W CARIBBEAN FROM COLOMBIA TO CUBA WITH SW WIND TRANSPORTING UPPER LEVEL MOISTURE FROM THE E PACIFIC ACROSS CENTRAL AMERICA INTO THE NW PORTION OF THE CARIBBEAN. MODERATE TO STRONG SUBSIDENCE AND DRY AIR COVER MUCH OF THE CARIBBEAN ESPECIALLY E OF 80W. WEAK HIGH PRES N OF THE AREA IS ALLOWING THE TRADES TO SLACKEN. ELY WINDS OF 15 TO 20 KT ARE FOUND JUST OFF THE COLOMBIAN COAST. LIGHTER WINDS ARE BLOWING ACROSS THE NW PORTION OF THE BASIN. TYPICAL FRAGMENTS OF LOW/MID CLOUDS WITH ISOLATED SHOWERS ARE OVER THE NE CARIBBEAN AND THE GREATER ANTILLES AS WELL AS OVER PARTS OF CENTRAL AMERICA. CLUSTERS OF MODERATE TO STRONG CONVECTION ARE OVER NORTHERN COLOMBIA ASSOCIATED WITH A DIFFLUENT PATTERN ALOFT AND THE TYPICAL LOW THAT SITS IN THIS AREA. THE COLD FRONT CURRENTLY OVER THE GULF IS FORECAST TO REACH THE YUCATAN CHANNEL AND WESTERN CUBA ON FRIDAY. ATLANTIC OCEAN... AN UPPER RIDGE/TROUGH/RIDGE PATTERN CONTINUES TO DOMINATE THE FORECAST AREA. A BROAD UPPER RIDGE EXTENDS FROM THE CARIBBEAN INTO THE W ATLC W OF 65W. A WEAK SURFACE RIDGE COVERS THE W ATLC AND THE FLORIDA PENINSULA. A DEEP LAYERED TROUGH IS IN THE CENTRAL ATLC N OF 15N FROM 35W-65W. THE ATTENDANT FRONTAL BOUNDARY EXTENDS SW AND THEN W FROM A 998 MB SFC LOW LOCATED N OF THE AREA TO 27N60W CONTINUING AS A SURFACE TROUGH TO 29N67W. THIS SYSTEM WITH GALE FORCE WINDS IS PRODUCING AN INCREASE IN WINDS AND SEAS OVER THE CENTRAL ATLC N OF 25N BETWEEN 40W-50W. AN UPPER RIDGE WITH AXIS ALONG 20W COVERS THE REMAINDER OF THE ATLC. WEAK HIGH PRES RIDGING LIES E OF 40W ANCHORED BY A 1019 MB HIGH BETWEEN THE CANARY AND MADEIRA ISLANDS NEAR 32N15W. SATELLITE IMAGERY SHOWS A BROAD BAND OF TRANSVERSE HIGH CLOUDS ASSOCIATED WITH A TROPICAL JETSTREAM FROM NE VENEZUELA ALL THE WAY NE TO THE AFRICAN COAST CROSSING N OF THE CAPE VERDE ISLANDS. $$ GR