000 AXNT20 KNHC 221709 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST FRI DEC 22 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... METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 5N8W 2N29W 5N46W 5N53W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM EITHER SIDE W OF 38W. ISOLATED MODERATE IS WITHIN 90 NM EITHER SIDE BETWEEN 10W-16W. ...DISCUSSION... GULF OF MEXICO... ABUNDANT MOISTURE REMAINS IN PORTIONS OF GULF...NOW SHIFTING A LITTLE TO E COVERING MUCH OF THE NRN HALF OF THE REGION. THERE ARE A FEW ELEMENTS PRODUCING THIS UNSETTLED WEATHER. FIRST IN THE UPPER LEVELS...A LARGE LOW PRES SYSTEM CONTINUES TO MOVE TO THE NE NOW CENTERED IN THE UPPER PLAINS. STRONG SWLY FLOW TO THE E OF THE LARGE CUT OFF ALONG WITH A SUBTROPICAL JET MERGING WITH THE UPPER FLOW IN PLACE IS ENHANCING INSTABILITY. AT THE SFC...THE FRONTAL BOUNDARY IS NOW ON THE MOVE...AFTER BEING NEARLY STATIONARY FOR THE PAST 18-24 HOURS...AND IS ANALYZED FROM ERN LA S-SW ALONG 26N92W 23N94W 20N96W. THE WEAK SFC LOW THAT HAS BEEN ALONG THE FRONT IS DROPPED FROM THE MAP AS LITTLE EVIDENCE ON SAT IMAGERY OR IN SFC OBS WAS APPARENT. DOPPLER RADAR SHOWS BANDS OF SCATTERED SHOWERS AND TSTMS IN THE WARM SECTOR FROM THE BIG BEND AREA OF FL TO SE LA. DOPPLER DERIVED ACCUMULATED RAINFALL PRODUCTS FROM THE SE SHOWS ISOLATED RAINFALL TOTALS TO 4-5 INCHES ACROSS PARTS OF CENTRAL GA. IR IMAGERY SHOWS MOISTURE STREAMING E TOWARDS THE FL PENINSULA AS THE COLD FRONT APPROACHES. THE WRN PERIPHERY OF THE SFC RIDGE STRETCHES ACROSS FLORIDA AND THE E GULF. THE TIGHTENED GRAD BETWEEN THIS HIGH PRES...CENTERED NEAR BERMUDA...AND LOWER PRES IN THE CENTRAL GULF IS GENERATING 20 TO 25 KT S TO SE WINDS IN THE E GULF AND THE FL BEACHES. THESE WINDS WILL SUBSIDE WITHIN THE NEXT 24 HOURS. LOOKING AHEAD...THE COLD FRONT WILL BECOME STATIONARY TONIGHT/TOMORROW BEFORE A STRONGER SECOND COLD FRONT...ASSOCIATED WITH A SHORT WAVE TROUGH CURRENTLY OVER THE WRN U.S...ENTERS THE WRN GULF SAT NIGHT. SEVERAL OF THE COMPUTER MODELS FORECAST A SFC LOW TO FORM ALONG THE FRONT LATE SAT/EARLY SUN AND TRACK IT NE ACROSS THE AREA. WINDS ARE FORECAST TO INCREASE TO GALE FORCE BEHIND THE FRONT IN THE WRN GULF ON SUN. CARIBBEAN SEA... AN UPPER LEVEL TROUGH IS SLOWLY SLIDING EASTWARD ACROSS THE CARIBBEAN WITH THE AXIS EXTENDING FROM THE WINDWARD PASSAGE TO PANAMA. A FAIR AMOUNT OF DRY STABLE AIR IN THE MID AND UPPER LEVEL RESIDES ACROSS THE WRN AND CNTRL PORTION...THANKS TO UPPER LEVEL CONFLUENT FLOW BETWEEN THIS TROUGH AND A STRONG MID TO UPPER LEVEL HIGH CENTERED OVER EL SALVADOR. UPPER LEVEL DIFFLUENCE...SOME LOW LEVEL CONVERGENCE ALONG WITH LOCAL UPSLOPE FLOW IS PRODUCING SCATTERED SHOWERS ACROSS THE DOMINICAN REPUBLIC AND ISOLATED ACTIVITY ACROSS ERN CUBA. THE ERN CARIBBEAN HAS MAINLY FAIR CONDITIONS LYING ON THE NW SIDE OF AN EXTENSIVE UPPER LEVEL RIDGE. 50-70 KT WLY UPPER LEVEL FLOW IS ADVECTING SOME HIGH CLOUDINESS ACROSS THE AREA S OF 14N. AT THE SFC...SHIP...BUOY AND QSCAT DATA SHOWS AN AREA OF 20-25 KT TRADE WINDS BETWEEN 68W AND 78W. THESE WINDS WILL LIKELY REMAIN AT THIS STRENGTH AND EXPAND EASTWARD OVER THE NEXT FEW DAYS AS HIGH PRES SETTLES IN THE SUBTROPICAL CENTRAL ATLC. GFS SHOWS THE TAIL END OF A COLD FRONT MOVING INTO THE NW CARIB ON MON. THIS FEATURE WILL BRING AN INCREASE IN MOISTURE AHEAD OF IT AND STRONG NLY WINDS AND INCREASE IN SEAS BEHIND IT. ATLANTIC OCEAN... A LONG WAVE RATHER FLAT DEEP-LAYERED RIDGE COVERS THE WRN ATLC W OF 60W. AN UPPER LEVEL TROUGH IN THE CARIB IS ERODING THE SRN PERIPHERY OF IT. BROKEN PATCHES OF MID TO HIGH CLOUDINESS IS ROTATING AROUND THE RIDGE...CONTAINED MOSTLY N OF 30N. A PAIR OF 1030 MB SFC HIGHS ARE CENTERED NEAR 31N61W AND NEAR 33N66W ENHANCING FAIR WEATHER ACROSS THE REGION. QSCAT DATA SHOWS NE-ELY WINDS NEAR 20 KT WITH A FEW 25 KT WIND VECTORS S OF 27N BETWEEN 60W-75W. THESE WINDS ARE DRIVING BROKEN LOW CLOUDS WITH POSSIBLE EMBEDDED ISOLATED SHOWERS ACROSS THE W ATLC WATERS. MODELS SHOWS THE SFC RIDGE GETTING PUSHED TO THE SE AND THEN BECOMING STATIONARY IN THE CENTRAL ATLC EARLY NEXT WEEK. A SHARP TROUGH LIES TO THE E OF THE RIDGE WITH THE UPPER LEVEL AXIS EXTENDING ALONG 32N41W 19N47W. THE ASSOCIATED FRONTAL BOUNDARY IS SLOW MOVING...ANALYZED AS STATIONARY ON THE 12Z MAP ALONG 32N38W 23N48W. MOIST SWLY UPPER LEVEL FLOW ALONG WITH SFC LIFT NEAR THE BOUNDARY IS GENERATING SCATTERED SHOWERS WITHIN 120 NM E OF THE FRONT. A MORE AMPLIFIED STACKED RIDGE LIES TO THE E OF THE TROUGH COVERING THE ATLC WATERS E OF 35W. PLENTY OF DRY AIR ALOFT IS ASSOCIATED WITH THE RIDGE KEEPING CONDITIONS STABLE UNDERNEATH IT. THERE IS A WEAK LINGERING SFC TROUGH ALONG 31W FROM 23N-33N MOVING W STEERED BY THE LOW-LEVEL FLOW. THIS FEATURE IS A BENIGN SWIRL OF LOW CLOUDS...ONLY CAUSING A WIND SHIFT AND MAYBE AN ISOLATED SHOWER WITHIN 120 NM. IN THE DEEP TROPICS...SWIFT UPPER LEVEL ZONAL FLOW ON THE N SIDE OF AN EXTENSIVE FLAT RIDGE WITH BROKEN HIGH CLOUDINESS IS COMMON. UPPER DIFFLUENCE NEAR THE W PERIPHERY OF THE RIDGE IS ENHANCING CONVECTION IN THE ITCZ W OF 40W. $$ CANGIALOSI