000 AXNT20 KNHC 170536 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST SUN FEB 17 2008 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC ...ITCZ... ITCZ AXIS IS CENTERED ALONG 5N10W 4N20W 5N40W EQ52W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 1N-7N EAST OF 21W. SIMILAR CONVECTION IS FROM 2N-7N BETWEEN 36W-51W. ...DISCUSSION... MEXICO/GULF OF MEXICO... A STRONG MID/UPPER LEVEL LOW IS ROTATING EWD FROM N TEXAS INTO OKLAHOMA. THE ASSOCIATED FRONTAL SYSTEM IS MOVING E ACROSS E/CENTRAL TEXAS AND NE MEXICO AND IS SPARKING SOME SEVERE THUNDERSTORMS ACROSS EASTERN TEXAS AND WESTERN LOUISIANA. THE FRONT IS FORECAST TO REACH FROM SE LOUISIANA TO NEAR VERACRUZ MEXICO BY SUN MORNING. THE AIR MASS BEHIND THE FRONT IS NOT ALL THAT COLD ALTHOUGH THERE IS A SHARP TEMPERATURE GRADIENT ACROSS THE MEXICAN PART OF THE BOUNDARY. SCATTERED SHOWERS AND TSTMS ARE EXPECTED TO MOVE OFF THE TEXAS COAST OVER THE NW GULF WATERS OVERNIGHT THEN PROGRESS EWD ACROSS THE NORTHERN PART OF THE GULF OVER THE NEXT FEW DAYS. IN THE MEANTIME...WEAK SURFACE AND UPPER LEVEL RIDGING IS IN CONTROL OVER THE GULF AND IS PRODUCING E/SE SURFACE WINDS WITH MAINLY FAIR WEATHER. CARIBBEAN SEA... STRONG UPPER LEVEL RIDGING IS CENTERED SW OF JAMAICA NEAR 16N78W WITH THE MID-LEVEL CENTER LOCATED OVER WESTERN CUBA...AND THIS IS RESULTING IN MODERATE/STRONG SUBSIDENCE OVER MUCH OF THE AREA. THE STRONGEST SUBSIDENCE AND PROBABLY THE AREA WITH THE LEAST AMOUNT OF CLOUDINESS IS LOCATED OVER THE SE CARIBBEAN AND WINDWARD ISLANDS...WITH UPPER MOISTURE GRADUALLY INCREASING FARTHER TO THE W. STRONG SLY WINDS ON THE WESTERN PERIPHERY OF THE RIDGE ARE ADVECTING UPPER LEVEL MOISTURE FROM THE EPAC ACROSS SOUTH MEXICO AND THE YUCATAN PENINSULA/CHANNEL INTO WESTERN CUBA. AS USUAL...POCKETS OF LOW LEVEL CLOUDS WITH EMBEDDED LIGHT SHOWERS ARE AFFECTING BETWEEN THE N LEEWARD ISLANDS AND HISPANIOLA. FRAGMENTS OF LOW LEVEL CLOUDS ARE ALSO SEEN OVER HONDURAS AND PARTS OF NICARAGUA. SCATTERED MODERATE CONVECTION IS NEAR THE PANAMA/COSTA RICA BORDER DUE TO THE CLOSE PROXIMITY OF THE EPAC ITCZ. SURFACE HIGH PRES LOCATED OVER THE W ATLC IS PRODUCING FRESH TO STRONG TRADES ACROSS THE CARIBBEAN WITH THE STRONGEST OCCURRING BETWEEN 68W AND 78W OFF THE COLOMBIAN COAST. WEST/CENTRAL ATLANTIC... BROAD UPPER RIDGE FROM THE CARIBBEAN EXTENDS N COVERING THE W ATLC WITH THE RIDGE AXIS ACROSS THE STATE OF FLORIDA. AN UPPER LEVEL TROUGH REMAINS OVER THE CENTRAL ATLC EXTENDING FROM 31N40W TO 10N52W. MAXIMUM WINDS WITHIN THE SUBTROPICAL JET ARE ABOUT 50 KT EXTENDING E OF FLORIDA BUT THERE IS VERY LITTLE ASSOCIATED HIGH CLOUDINESS WITH THE FLOW. A DYING FRONTAL BOUNDARY IS NOTED IN SATELLITE IMAGERY EXTENDING FROM 31N43W TO 27N58W. A SFC TROUGH...REMNANTS OF THE SAME FRONTAL BOUNDARY EXTENDS FROM 28N70W TO THE NW BAHAMAS. PATCHY LOW CLOUDS LIE IN THE VICINITY OF THE BOUNDARY AND THE TROUGH...BUT OVERALL THERE IS LITTLE SIGNIFICANT WEATHER. THE LEFTOVER BOUNDARY LIES WITHIN A SURFACE RIDGE WITH A 1023 MB HIGH LOCATED JUST SE OF BERMUDA NEAR 31N60W. EAST ATLANTIC... BROAD SOUTHWEST TO WESTERLY UPPER LEVEL FLOW COVERS THE REMAINDER OF THE ATLC BASIN...FEEDING INTO A COMPLEX UPPER LOW LOCATED BETWEEN THE CANARY ISLANDS AND THE AZORES. A 1002 MB OCCLUDED LOW IS LOCATED JUST N OF THE AREA NEAR 33N21W AND THE ASSOCIATED COLD FRONT EXTENDS INTO THE AREA FROM 31N13W CROSSING JUST E OF THE CANARY ISLANDS TO 21N28W. THERE ARE TWO WIND MAXIMA ASSOCIATED WITH THE SUBTROPICAL JET ON THE SE PERIPHERY OF THE LOW. ONE CORE ROTATES BETWEEN THE CANARY AND THE MADEIRA ISLANDS WITH MAXIMUM WINDS OF 110 KT WHILE THE SECOND LIES JUST N OF THE CAPE VERDE ISLANDS INTO WESTERN SAHARA WITH MAXIMUM WINDS OF 90 KT. A STREAM OF HIGH CLOUDS RUNS ALONG THE SECOND JET BEGINNING NEAR 10N45W IN THE TROPICS AND EXTENDING TOWARDS NORTHERN MAURITANIA AND WESTERN SAHARA. SCATTERED MODERATE CONVECTION IS OCCURRING E OF THE OCCLUDED LOW N OF 30N BETWEEN CENTRAL MOROCCO AND 20W. $$ GR