000 AXNT20 KNHC 091742 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST SAT DEC 09 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 5N9W 4N28W 3N45W 3N54W. ISOLATED TO SCATTERED MODERATE IS WITHIN 300 NM N OF THE AXIS W OF 37W ENHANCED BY A UPPER LEVEL JET TO THE N. ...DISCUSSION... THE GULF OF MEXICO... A SLOWLY LIFTING MID/UPPER LEVEL SHORTWAVE TROUGH LIES ABOVE THE WRN GULF FROM ERN TEXAS/LOUISIANA TO THE BAY OF CAMPECHE. A SUBTROPICAL JET EXISTS AT THE BASE OF THIS TROUGH AND EXTENDS ACROSS THE S GULF AND THE STRAITS OF FLORIDA WITH CORE WINDS NEAR 100 KT BASED ON CIMSS DERIVED UPPER LEVEL WINDS. UPPER LEVEL DIFFLUENCE IS PRODUCING WIDESPREAD CLOUDINESS ACROSS THE REGION. AT THE SFC...STRONG HIGH PRES CENTERED OVER THE SE U.S. IS PRODUCING STIFF NE FLOW ACROSS THE AREA...STRONGEST IN THE ERN GULF WHERE BUOYS ARE REPORTING WINDS BETWEEN 20-30 KT. A COUPLE WEAK PERTURBATIONS...SFC TROUGHS...ARE EMBEDDED IN THE LOW-LEVEL FLOW. ONE IS IN THE ERN GULF ALONG 85W FROM 24N-29N AND THE OTHER IS IN THE BAY OF CAMPECHE ALONG 94W FROM 17N-22N. BOTH OF THESE ARE PRODUCING A LOW-LEVEL CONVERGENT LINE OF CLOUDS AND A KINK IN THE ISOBARIC PATTERN. SOME SFC LIFT AND THE WIDESPREAD MID-HIGH LEVEL MOISTURE IN PLACE IS GENERATING SCATTERED SHOWERS AND TSTMS ALONG THE S TX/NRN MEXICAN COAST AND OFFSHORE WATERS AND LIGHTER SCATTERED SHOWER ACTIVITY IN THE STRAITS OF FLA AS DEPICTED ON MOSAIC DOPPLER RADAR FROM THE SE. SCATTERED SHOWERS ARE ALSO LIKELY OCCURRING N OF 24N W OF 85W AS IR IMAGERY SHOWS AREAS OF CLOUD TOPS TEMPS BETWEEN -50 AND -60 C. THE STRONG HIGH PRES SYSTEM WILL SLOWLY SLIDE E ALLOWING WINDS TO SLACKEN A LITTLE BUT THEY WILL REMAIN QUIET BREEZY TO WINDY IN THE E GULF OVER THE NEXT COUPLE DAYS AS THE PRES GRAD REMAINS FAIRLY TIGHT. A COLD FRONT MAY ENTER THE NW GULF LATE TUE. GFS SHOWS A FAIR AMOUNT OF MOISTURE LINGERING AND INCREASING AHEAD OF THE FRONT. CARIBBEAN SEA... THE TAIL END OF AN ATLC FRONTAL BOUNDARY IS STATIONARY FROM THE WINDWARD PASSAGE TO NEAR THE COAST OF NICARAGUA ALONG 20N74W 18N79W 13N83W. LOW-LEVEL LIFT NEAR THE BOUNDARY ALONG WITH MOIST SWLY UPPER LEVEL FLOW ON THE W PERIPHERY OF AN UPPER RIDGE ALONG 76W IS GENERATING SCATTERED SHOWERS AND TSTMS WITHIN 240 NM W OF THE FRONT S OF 20N. NE WINDS IN THE 20 TO 25 KT RANGE ARE COMMON BEHIND THE FRONT. CONDITIONS ARE PRETTY QUIET IN THE CNTRL AND ERN CARIBBEAN AS MODERATELY DRY AIR...ASSOCIATED WITH NLY FLOW ON THE E SIDE OF THE UPPER RIDGE...LIES ABOVE THE AREA. THERE ARE TYPICAL LOW LEVEL PATCHES OF MOISTURE DRIVEN BY RATHER STRONG ELY TRADES UNDERNEATH THE SUBSIDENCE INVERSION. SAN JUAN DOPPLER RADAR SHOWS SCATTERED SHOWERS MOVING ACROSS PUERTO RICO WITH DEEPER MOISTURE TO THE N/NW CLOSER TO THE FRONT. STRONG NE TO E WINDS WILL CONTINUE OVER THE AREA THROUGH TUE AS STRONG HIGH PRES REMAINS N OF THE REGION. THE FRONT OR MORE LIKELY REMNANT TROUGH WILL SLOWLY WEAKEN OVER THE NEXT FEW DAYS. THE ATLANTIC OCEAN... A STRONG COLD FRONT IS IN THE WRN/CENTRAL ATLC ALONG 32N56W 23N68W TO THE WINDWARD PASSAGE. BEHIND THE FRONT...STRONG SFC HIGH PRES IS BUILDING IN ANCHORED BY A 1037 MB HIGH IN THE CAROLINAS. THE TIGHT PRES GRAD IS GENERATING NE WINDS MAINLY IN THE 20-30 KT RANGE ACROSS THE SUBTROPICAL W ATLC. STRONG W-SWLY UPPER LEVEL FLOW ALSO EXISTS AS PART OF THE SUBTROPICAL JET RACES ACROSS THE AREA PRODUCING CONSIDERABLE CLOUDINESS. ALONG AND JUST AHEAD OF THE FRONT...SFC LIFT AND AMPLE SWLY UPPER LEVEL FLOW IS SUPPORTING SCATTERED SHOWERS AND TSTMS WITHIN 240 NM E OF THE BOUNDARY. FARTHER E...THE SFC PATTERN IN THE CNTRL AND ERN ATLC IS DOMINATED BY A STRONG 1042 MB HIGH IN THE AZORES. THIS STRONG RIDGE IS CAUSING A LARGE AREA OF MODERATE TO STRONG WINDS E OF 50W ESPECIALLY N OF 15N. THE MID TO UPPER LEVEL PATTERN IN THE CNTRL AND ERN ATLC IS QUITE AMPLIFIED WITH A NARROW TITLED RIDGE STRETCHES NE FROM THE CARIBBEAN ALONG 23N57W 32N46W. A LARGE HIGHLY ELONGATED UPPER LEVEL TROUGH STRETCHES FROM THE IBERIAN PENINSULA TO A WELL-DEFINED UPPER LOW NEAR 23N34W CONTINUING SW TO THE DEEP TROPICS NEAR 13N51W. A TROPICAL/SUBTROPICAL JET ORIGINATES NEAR THE BASE OF THE TROUGH AND EXTENDS NE ALONG 17N31W 23N22W 28N13W. STRONG SWLY UPPER LEVEL FLOW ASSOCIATED WITH THE JET IS DRAWING MOISTURE FROM THE ITCZ AND SPREADING IT ACROSS THE E ATLC E OF THE JET AXIS. W OF THE JET AXIS...PLENTY OF DRY STABLE AIR ALOFT EXISTS OUT TO 45W EXCEPT FOR WITHIN 300-400 NM OF THE UPPER LOW...WHICH HAS MOISTENED THE ENVIRONMENT POSSIBLY GENERATING ISOLATED SHOWERS. $$ CANGIALOSI