000 AXNT20 KNHC 011738 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST FRI FEB 01 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 3N10E 1N10W 3N30W 2N40W CROSSING THE EQUATOR NEAR 45W TO 1S47W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS S OF 3N W OF 41W. SIMILAR CONVECTION IS WITHIN 60 NM OF THE AXIS BETWEEN 17W-19W. ...DISCUSSION... GULF OF MEXICO... COLD FRONT CONTINUES SE PROGRESS AS IT WEAKENS ANALYZED FROM N FLORIDA TO S MEXICO ALONG 30N83W 24N87W 18N94W AT 15Z. TIGHTENED PRES GRADIENT BETWEEN THE FRONT AND A 1029 MB HIGH OVER EXTREME S TEXAS IS PRODUCING 20-30 KT N TO NW WINDS BEHIND THE FRONT...HOWEVER...THESE WINDS SHOULD DECREASE RATHER RAPIDLY THROUGH TONIGHT AS THE FRONT WASHES OUT OVER SOUTH FLORIDA AND THE SE GULF. DOPPLER RADAR AND LIGHTNING DATA INDICATE A STEADY DECLINE IN THE TSTM ACTIVITY OVER THE PAST SEVERAL HOURS WITH ONLY ONE PATCH REMAINING ALONG THE BOUNDARY FROM 24N-25N BETWEEN 85W-87W. SCATTERED SHOWERS EXIST ELSEWHERE WITHIN 90 NM E OF THE FRONT. BEHIND THE FRONT...A DRY AND COOL AIRMASS HAS BUILT IN BUT EXPECTED TO QUICKLY MODIFY BY TOMORROW AS THE HIGH SHIFTS E INTO THE ATLC ALLOWING E TO SE FLOW TO DEVELOP. CARIBBEAN SEA... MID TO UPPER RIDGE REMAINS ANCHORED ALONG 76W/77W WHILE TROUGHING LIES OVER THE E CARIB INDUCED BY A WELL DEFINED UPPER CUT OFF NE OF THE LESSER ANTILLES. THE UPPER LOW HAS AN ASSOCIATED HIGHLY ELONGATED SFC TROUGH LYING JUST E OF THE AREA. LOW-LEVEL CONVERGENCE ALONG THIS BOUNDARY IS GENERATING SCATTERED SHOWER ACTIVITY SOME OF WHICH ARE DRIVEN SWD INTO THE E CARIB BY NLY FLOW ON THE W SIDE OF THE TROUGH AXIS. HOWEVER...ALL OF THIS MOISTURE IS SHALLOW IN NATURE CAPPED BY ABUNDANT SUBSIDENCE REGION-WIDE. THE SHALLOW MOISTURE PATCHES THIN OUT W OF 75W AS THE LOW-LEVEL FLOW WEAKENS AND DEVELOPS MORE OF AN ELY COMPONENT. A COLD FRONT IS NOT FAR FROM THE NW CORNER BUT IT IS EXPECTED TO FIZZLE AS IT NEARS CLOSER. ATLANTIC OCEAN... AMPLIFIED MID TO UPPER RIDGE ORIGINATING IN THE CARIBBEAN EXTENDS NWD OVER THE W ATLC ALONG 74W/75W. A FAIRLY VIGOROUS SHORTWAVE OVER THE GREAT LAKES IS ERODING THE W SIDE OF THE RIDGE SLIGHTLY...BUT NOT EXPECTED TO HAVE MUCH MORE OF AN IMPACT IN THE SUBTROPICS AS IT LIFTS NE. FOR THAT REASON THE COLD FRONT IN THE E GULF IS EXPECTED TO WEAKEN AS IT ENTERS THE ATLC WATERS. SCATTERED SHOWERS HAVE SPREAD INTO THE FAR NW CORNER AHEAD OF THE FRONT. AN UPPER CUT OFF LOW HAS DRIFTED FAIRLY FAR S INTO THE TROPICS CENTERED NEAR 18N57W. AN ASSOCIATED ELONGATED SFC TROUGH IS ANALYZED ALONG 27N68W 20N60W 10N56W. INSTABILITY NEAR THE UPPER CENTER IS GENERATING SCATTERED SHOWERS AND ISOLATED TSTMS FROM 15N-21N BETWEEN 53W-58W WHILE SCATTERED SHOWERS EXIST ELSEWHERE WITHIN 300 NM OF THE TROUGH AXIS. A SIMILAR SCENARIO EXISTS ABOUT 1000 NM TO THE NE WHERE A MUCH BROADER UPPER LOW IS CENTERED NEAR 27N35W. A RELATED SFC TROUGH LIES NEARLY DIRECTLY BENEATH THE UPPER LOW ALONG 38W/39W FROM 20N-28N. SCATTERED SHOWERS AND TSTMS ARE FROM 22N-28N BETWEEN 31W-40W. THIS SFC TROUGH AND THE ONE FARTHER W IS ENHANCING NE TO E TRADES ACROSS THE SUBTROPICAL ATLC E OF ABOUT 65W-70W. $$ CANGIALOSI