000 AXNT20 KNHC 131705 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE MAR 13 2012 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1600 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS W AFRICA INTO THE E TROPICAL ATLC NEAR 07N12W TO 05N14W...WHERE THE ITCZ AXIS CONTINUES TO S OF THE EQUATOR NEAR 30W INTO SOUTH AMERICA NEAR 03S44W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE S OF THE EQUATOR BETWEEN 22W-37W. ...DISCUSSION... GULF OF MEXICO... A PERSISTENT HIGH PRES RIDGE OVER THE GULF COAST EXTENDING ALONG 30N WILL CHANGE VERY LITTLE THROUGH THE WEEKEND. A WEAK HIGH IS EXPECTED TO PINCH OFF NEAR PENSACOLA WED NIGHT AS THE BERMUDA HIGH SHIFTS EAST. MODERATE E-SE TRADE WINDS WILL CONTINUE ACROSS THE ENTIRE GULF THROUGH FRI THEN FRESHEN TO AROUND 20 KT W OF 90W SUN AS A SLOW MOVING TROUGH OF LOW PRESSURE BECOMES ENTRENCHED OVER THE WESTERN GREAT PLAINS AND FRONT RANGE OF THE ROCKIES. SATELLITE IMAGERY SHOWS A SMALL AREA OF PERSISTENT SHOWERS IN THE SE GULF NEAR 24N86W. SCATTEROMETER DATA FROM LAST NIGHT AROUND 0300 UTC SHOWED LOW LEVEL SPEED CONVERGENCE FROM WINDS DECELERATING WEST OF THE FLORIDA STRAITS...WHICH APPEARS TO BE THE PRIMARY FACTOR FOR SHOWERS REPEATEDLY DEVELOPING IN THE SAME LOCATION. THE REMAINDER OF THE GULF HAS MOSTLY CLEAR TO PARTLY CLOUDY SKIES WITH FEW SHOWERS. CARIBBEAN SEA... SCATTEROMTER DATA AT 0300 UTC LAST NIGHT SHOWED AN AREA OF 30-35 KT WINDS WITHIN ABOUT 75 NM OF THE COAST OF COLOMBIA NEAR 12N74W. SHIP OBSERVATIONS FROM CRUISE SHIP CELEBRITY EQUINOX CALL SIGN 9HXD9 OVER THE PAST 12 HOURS HAVE ALSO INDICATED GALE FORCE WINDS WERE PRESENT S OF 13N BETWEEN 73W-77W EARLIER TODAY. THE NEXT SCATTEROMETER PASSES TODAY MISSED THE AREA OF HIGHEST WINDS...BUT MODEL GUIDANCE FROM GFS AND ECMWF SUGGEST WINDS ALONG THE COAST OF COLOMBIA SHOULD DIMINISH SLIGHTLY BY ABOUT 3-5 KT...TO 30 KT OR LESS BY TONIGHT. PERSISTENT 1008 MB LOW PRES NEAR 10N75W AND MODERATE HIGH PRES RIDGE N OF THE AREA ALONG 30N IS ACTING TO MAINTAIN THIS AREA OF VERY STRONG WINDS IN THE CENTRAL CARIBBEAN. LITTLE CHANGE TO THE CURRENT SYNOPTIC PATTERN IS EXPECTED THROUGH SAT. FRESH TRADE WINDS WILL PREVAIL ELSEWHERE IN THE CARIBBEAN BASIN...WITH HIGHEST WINDS AND SEAS EXPECTED S OF 18N BETWEEN 68W AND 82W. SATELLITE IMAGERY SHOWS RANDOM CONVECTION DUE TO TRADE WIND CONVERGENCE OVER MOST OF THE REGION...AND SMALL CLUSTERS OF MODERATE SHOWERS MOVING DOWNWIND FROM HISPANOLA AND JAMAICA NEAR 17N77W AND 16N77W. ATLANTIC OCEAN... QUASI-STATIONARY HIGH PRES NEAR 33N60W WILL PERSIST THROUGH WED NIGHT THEN SHIFT EASTWARD AS A FRONT PUSHES OFF THE EAST COAST OF THE U.S. THU. THE FRONT WILL BRUSH PAST 32N WITH LITTLE EFFECT IN THE TROPICS THROUGH SAT THEN DISSIPATE IN THE CENTRAL ATLC SAT NIGHT. HIGH PRES WILL REDEVELOP NEAR 33N68W ON FRI AS THE FRONT SLIDES EAST AND WEAKENS. 1014 MB LOW IS LOCATED NEAR 34N41W WITH A COLD FRONT TRAILING SW TO 27N46W. SCATTEROMETER DATA SHOWS 20 TO 30 KT SOUTHERLY WINDS N OF 30N ASSOCIATED WITH THIS FEATURE. THE LOW WILL BECOME STATIONARY OVER THE NEXT 12-24 HOURS AS IT ENCOUNTERS A STUBBORN BLOCKING HIGH NEAR THE AZORES...WHICH WILL CAUSE THE LOW TO WEAKEN THROUGH WED EVENING THEN DISSIPATE INTO A TROUGH ALONG 40W WED NIGHT AND THU. THIN VEIL OF SAHARAN DUST COVERS A BROAD AREA W-SW OF THE AFRICAN CONTINENT TODAY FROM THE ITCZ TO 27N E OF 42W...AND IS BECOMING MORE DIFFUSE. SATELLITE IMAGERY SHOWS RANDOM LIGHT TO MODERATE TRADE WIND SHOWERS ACROSS MOST OF THE REGION WITH NO ORGANIZED AREAS OF DEEP CONVECTION. VERY LITTLE CHANGE TO THE SYNOPTIC PATTERN EXPECTED THROUGH SUN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MUNDELL