000 AXNT20 KNHC 270526 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST MON NOV 27 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 7N12W 5N30W 6N45W 4N54W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM EITHER SIDE OF THE AXIS E OF 21W. THE REMAINDER OF THE AXIS IS RATHER QUIET WITH ONLY PATCHES OF ISOLATED MODERATE FROM 4N-8N BETWEEN 25W-34W. ...DISCUSSION... THE GULF OF MEXICO... THE WEATHER ACROSS THE GULF REMAINS FAIRLY UNEVENTFUL AS SFC HIGH PRES CONTINUES TO DOMINATE THE AREA. BREEZY 15-20 KT NE TO E WINDS IN THE ERN AND CNTRL GULF IS ADVECTING SOME LOW-LEVEL CLOUDS AND ISOLATED SHOWERS ACROSS CENTRAL AND SOUTH FLORIDA ON THE BREEZE WITH SOME BROKEN CLOUDS PUSHING W ACROSS THE GULF WATERS. HOWEVER BECAUSE OF THE WIDESPREAD STRONG SUBSIDENCE ABOVE THE LOW-LAYER OF MOISTURE THERE IS LIMITED DEPTH TO THE CLOUDS. THE SFC FLOW IS A LITTLE LIGHTER AND IS MORE ESELY IN THE WRN GULF FLOWING CLOCKWISE AROUND THE SFC HIGH. IN THE UPPER LEVELS...A PRONOUNCED RIDGE EXTENDS FROM THE EPAC ACROSS SRN MEXICO INTO THE CENTRAL GULF. SLIGHT UPPER TROUGHING IS LIFTING OUT BUT STILL LIES ABOVE FLORIDA. GFS SHOWS THE UPPER AND SFC RIDGE BUILDING E. THIS SHOULD ALLOW TEMPS TO REMAIN SLIGHTLY ABOVE NORMAL VALUES OVER THE NEXT FEW DAYS. THE NEXT AIRMASS CHANGE IS ANTICIPATED TO AFFECT THE AREA LATE IN THE WEEK AS A POTENTIAL STRONG COLD FRONT APPROACHES THE NW PORTION ON THU. THE CARIBBEAN SEA... THE UNSETTLED WEATHER THAT HAS BEEN IN THE SW CARIBBEAN OVER THE PAST SEVERAL DAYS...ASSOCIATED WITH A NEARLY STATIONARY SFC LOW PRES TROUGH ALONG 77W FROM 10N-17N...HAS DIMISHED. THE FEATURE IS STILL EVIDENT BUT IS NOW VERY SHALLOW WITH ONLY LOW TO MID-LEVEL CLOUDS ROTATING ABOUT THE AXIS. THE TAIL END OF A SLOWLY WEAKENING STATIONARY FRONT EXTENDS ACROSS THE WINDWARD PASSAGE TO JUST W OF JAMAICA NEAR 18N76W. DEEP MOISTURE IS VERY LIMITED ALONG THE FRONT WITH ONLY ISOLATED SHOWERS WITHIN 120 NM OF THE SFC BOUNDARY. A VERY BROAD FLAT UPPER LEVEL RIDGE...CENTERED OVER VENEZUELA...IS ADVECTING SOME MOISTURE FROM THE ITCZ AND SPREADING IT ABOVE THE SFC FRONT INTO THE ATLC. HOWEVER...AS MENTIONED...THE MOISTURE IN THE AREA IS NOTICEBLY THINNER THAN IT HAS BEEN WITH ONLY BROKEN MID-HIGH LEVEL CLOUDINESS AND EMBEDDED ISOLATED SHOWERS NOTED BETWEEN 72W-83W. VERY DRY AIR/STRONG SUBSIDENCE LIES ABOVE THE ERN AND THE EXTREME WRN CARIB SUPPRESSING ANY DEEP CLOUDINESS. TRADES ARE MODERATE AND WILL LIKELY REMAIN THAT WAY OVER THE NEXT COUPLE DAYS. LATER THIS WEEK...THESE WINDS WILL LIKELY INCREASE AS THE FRONTAL BOUNDARY PULLS NE AND WEAKENS AND STRONG HIGH PRES DEVELOPS TO THE N. THE ATLANTIC OCEAN... WEAK UPPER TROUGHING...VERY DRY AIR ALOFT AND PATCHES OF LOW-LEVEL MOISTURE UNDERNEATH THE STRONG MID-LEVEL CAP COVERS THE AREA W OF A PERSISTENT FRONTAL BOUNDARY IN THE CNTRL/WRN ATLC. THE FRONT IS ASSOCIATED WITH AN OCCLUDED 1014 MB LOW NEAR 32N58W AND IS PROGRESSIVE...COLD FRONT...ALONG 32N55W 27N59W THEN STATIONARY TO THE WINDWARD PASSAGE. MULTILAYERED CLOUDS WITH EMBEDDED SCATTERED SHOWERS ARE ASSOCIATED WITH THE WEAK LOW/FRONTAL BOUNDARY AND EXTEND WITHIN 240 NM E OF THE FRONT N OF 27N AND WITHIN 150 NM EITHER SIDE S OF 27N. A SHORTWAVE UPPER TROUGH STRETCHES FROM 32N30W 23N41W TO AN UPPER LOW IN THE DEEP TROPICS NEAR 9N53W. ELONGATED RIDGING LIES E OF THE SHORTWAVE AND COVERS THE REMAINDER OF THE E ATLC. THIS UPPER LEVEL PATTERN IN THE E ATLC HAS SIGNIFICANTLY FLATTENED TODAY AS THE SHORTWAVE TROUGH HAS HELPED TO BREAK DOWN THE ONCE AMPLIFED UPPER LEVEL RIDGE. AN UPPER LEVEL HIGH IS LOCATED IN THE TROPICAL ATLC E OF THE UPPER LOW NEAR 9N39W. UPPER LEVEL DIFFLUENCE BETWEEN THE UPPER LOW AND HIGH IS GENERATING ISOLATED TO SCATTERED SHOWERS FROM 10N-17N BETWEEN 39W-52W...BUT THIS ACTIVITY IS MUCH WEAKER THAN IT HAS BEEN THE PAST FEW DAYS DUE TO THE FLATTENING PATTERN. PLENTY OF DRY STABLE AIR ALOFT IS LOCATED E OF 30W ENHANCED BY UPPER LEVEL CONFLUENT FLOW. AT THE SFC...WEAK TO MODERATE HIGH PRES RIDGING IS THE RULE ACROSS THE SUBTROPICAL ATLC SUPPORTED BY A 1023 MB HIGH NEAR 30N22W. THIS RIDGING IS INTERRUPTED BY THE FRONTAL BOUNDARY/WEAK LOW MENTIONED IN THE CNTRL ATLC. $$ CANGIALOSI