000 AXNT20 KNHC 222348 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST WED NOV 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...WEATHER OBSERVATIONS...RADAR... AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 5N10W 5N20W 5N30W 4N40W 4N52. SCATTERED MODERATE CONVECTION IS FROM 2N-6N BETWEEN 28N-33N. SIMILAR CONVECTION IS MAINLY WITHIN 120 NM SOUTH OF THE AXIS BETWEEN 35W-44W. CLUSTERS OF MODERATE CONVECTION ARE ALSO AFFECTING THE NORTHERN PORTION OF FRENCH GUIANA AND SURINAME. ...DISCUSSION... THE GULF OF MEXICO... A DEEP LAYER TROUGH RUNS FROM A STRONG CUT-OFF LOW LOCATED OFF THE GEORGIA/CAROLINAS COAST ACROSS THE FLORIDA PENINSULA AND WESTERN CUBA TO THE NW CARIBBEAN. THIS SYSTEM WILL SLOWLY DRIFT NE AFFECTING THE EASTERN SEABOARD OF THE U.S. AN UPPER LEVEL RIDGE EXTENDS NORTH ALONG THE MEXICAN GULF COAST AND TEXAS. STRONG NLY MID-UPPER LEVEL FLOW AND VERY DRY AIR DOMINATE THE ENTIRE GULF. AT THE SFC...HIGH PRES IS IN CONTROL OF THE WEATHER ACROSS THE AREA. AS OF 2100 UTC...A 1025 MB HIGH IS CENTERED OVER THE NW CORNER OF THE GULF NEAR 27N94W. THIS FEATURE WILL CONTINUE TO WEAKEN TONIGHT WITH WINDS AND SEAS SUBSIDING THROUGH FRIDAY OVER MOST OF THE AREA. COLD AIR STRATOCUMULUS CLOUDS ARE STILL COVERING PORTIONS OF FLORIDA...THE SE GULF AND THE BAY OF CAMPECHE. THE REMAINDER OF THE GULF IS MOSTLY CLEAR. 15-20 KT NLY WINDS STILL EXIST IN THE CNTRL AND ERN GULF. THESE WINDS CONTINUE TO ADVECT COLD AIR INTO THE REGION...INCLUDING THE FLORIDA PENINSULA WHERE NEAR RECORD LOWS ARE EXPECTED TONIGHT PARTICULARLY ACROSS THE INTERIOR. AS THE UPPER LOW MOVES AWAY FROM THE SE U.S. AND HIGH PRESSURE TAKES CONTROL OF THE REGION THE AIRMASS WILL GRADUALLY MODIFY WITH TEMPERATURES RETURNING TO THE NORMAL VALUES FOR THIS TIME OF THE YEAR DURING THE UPCOMING WEEKEND. THE CARIBBEAN SEA... CLUSTERS OF MODERATE/ISOLATED STRONG CONVECTION CONTINUES TO AFFECT THE CENTRAL CARIBBEAN SEA MAINLY BETWEEN 73W-78W. A DIFFLUENT PATTERN ALOFT IS ENHANCING THIS CONVECTIVE ACTIVITY. THIS UNSETTLED WEATHER IS ASSOCIATED WITH A STATIONARY FRONT THAT EXTENDS FROM PANAMA TO THE WINDWARD PASSAGE/HAITI AND A BROAD AREA OF LOW PRESSURE THAT REMAINS SOUTH OF JAMAICA. COLD AIR STRATOCUMULUS CLOUDS CONTINUES TO INVADE THE NW CARIBBEAN AND MUCH OF CUBA. 20-25 KT NLY WINDS ARE STILL BLOWING BEHIND THE FRONT. EAST OF THE FRONT...PATCHES OF MOISTURE WITH EMBEDDED SHOWERS ARE BEING CARRIED BY THE TRADE WINDS. ONE OF THIS AREA OF MOISTURE IS MOVING ACROSS THE LEEWARD/VIRGIN ISLANDS TOWARD PUERTO RICO. IN THE UPPER LEVELS...AN UPPER HIGH LOCATED VERY CLOSE TO THE COAST OF NICARAGUA EXTENDS A RIDGE ACROSS THE CENTRAL CARIBBEAN AND HISPANIOLA INTO THE CENTRAL ATLANTIC. THE BASE OF THE AFOREMENTIONED DEEP LAYERED TROUGH IS OVER THE NW CARIBBEAN WHILE AN UPPER LOW HAS DEVELOPED OVER NE VENEZUELA GENERATING SOME SHOWER ACTIVITY OVER EASTERN VENEZUELA AND TRINIDAD/TOBAGO ISLANDS. DRY AIR ALOFT...ON THE WEST SIDE OF THE LOW COVERS THE E CARIBBEAN. ACCORDING TO THE GFS MODEL...THE FRONTAL BOUNDARY WILL REMAIN NEARLY STATIONARY OVER THE NEXT 12-24 HOURS...THEN IT WILL BEGIN TO SLOWLY PUSH BACK TO THE WEST BY THE TRADE WINDS. THE ATLANTIC OCEAN... A PRONOUNCED TROUGH/RIDGE/TROUGH PATTERN DOMINATES THE ATLANTIC. A STRONG LOW PRESSURE SYSTEM IS OVER THE SE U.S. DOPPLER RADAR CONTINUES TO SHOW BANDS OF NUMEROUS SHOWERS AND TSTMS ON THE COLD BACK SIDE OF THE LOW AFFECTING THE MID ATLANTIC STATES. THE ATTENDANT COLD FRONT ENTERS THE AREA NEAR 32N67W...THEN CONTINUES SW TO THE SOUTHERN BAHAMAS WHERE IT BECOMES STATIONARY EXTENDING ACROSS THE CENTRAL CARIBBEAN. THIS SFC BOUNDARY ALONG WITH UPPER DIFFLUENCE IS GENERATING A CONSIDERABLE AMOUNT OF MOISTURE BETWEEN 66W-73W. W OF THE FRONT...MUCH COLDER AIR IS ADVECTED BY STRONG W-NWLY WINDS. A STRONG MID-UPPER LEVEL RIDGE COVERS THE W-CENTRAL ATLC WITH VERY DRY AIR/SUBSIDENCE FROM 20N-30N BETWEEN 40W-66W. A HIGHLY ELONGATED TROUGH IS LOCATED E OF THE RIDGE WITH SEVERAL UPPER LEVEL LOWS EMBEDDED FROM A LARGE CUT OFF LOW LOCATED JUST NORTH OF THE CANARY ISLANDS TO A SMALL UPPER LOW NEAR 22N50W EXTENDING DEEP INTO THE TROPICS TO A BROAD UPPER LOW OVER NE VENEZUELA. S OF 20N E OF THE CARIBBEAN... WV IMAGERY SHOWS A BROAD BAND OF UPPER LEVEL MOISTURE WITH EMBEDDED SHOWERS ASSOCIATED WITH A TROPICAL JETSTREAM. AT THE SFC...HIGH PRES IS THE RULE E OF THE WRN ATLC FRONTAL BOUNDARY ANCHORED BY A 1027 MB HIGH NEAR 33N42W AND A 1026 MB HIGH SE OF THE AZORES NEAR 34N23W. THIS STRONG RIDGING IS INTERRUPTED A BIT BY A WEAK 1018 MB LOW NEAR 22N35W...WHICH IS ASSOCIATED WITH THE LARGE CUT OFF LOW SYSTEM MENTIONED ABOVE. THE LOW IS ONLY A SWIRL OF LOW CLOUDS. $$ GR