000 AXNT20 KNHC 121145 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST FRI FEB 12 2010 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1145 UTC. ...THE ITCZ... THE ITCZ AXIS IS CENTERED FROM THE NORTHERN LIBERIA COAST NEAR 6N11W...WESTWARD ALONG 3N20W 2N30W 1N40W EQ50W. MODERATE TO STRONG CONVECTION IS ALONG THE ITCZ BETWEEN 45W AND 50W. SIMILAR CONVECTION IS BETWEEN 11W AND 15W. WEAK TO MODERATE CONVECTION IS FROM 2S TO 3N BETWEEN 20W AND 30W. ...DISCUSSION... THE GULF OF MEXICO... WATER VAPOR IMAGERY SHOWS STRONG SUBSIDENCE OF AIR OVER THE FAR NW BASIN. THIS FEATURE IS COMING FROM AN UPPER LEVEL SHORTWAVE ENTERING THIS REGION...SUPPORTING A SURFACE 1000 MB LOW NEAR 28N90W. THIS SYSTEM IS DEEPENING RATHER QUICKLY AND IT IS MOVING EASTWARD TOWARDS THE NORTHERN FLORIDA PENINSULA. A COLD FRONT EXTENDS SOUTHWEST FROM THE LOW CENTER TO VERACRUZ MEXICO NEAR 19N96W. A WARM FRONT ALSO EXTENDS NORTHEAST FROM THE LOW CENTER TO NEAR 27N84W. SATELLITE DATA SHOWS MODERATE TO STRONG CONVERGENCE WITHIN 100 NM ON EITHER SIDE OF THE COLD FRONT...AND WITHIN 200 NM NORTH OF THE WARM FRONT. DOPPLER RADAR IMAGERY INDICATES THIS SYSTEM IS BRINGING PRECIPITATION TO THE NORTHERN GULF COAST...FROM THE EASTERN TEXAS COAST TO THE NORTHWEST FLORIDA COAST. MARINE OBSERVATIONS ACROSS THE BASIN SHOW CYCLONIC FLOW 15 TO 25 KT...WITH GALE FORCE WINDS WITHIN 70 NM OFF THE COAST OF MISSISSIPPI...ALABAMA...AND NORTHWEST FLORIDA COAST. THIS SYSTEM IS ALSO LEAVING A SIGNIFICANT COOL AND DRY AIRMASS ACROSS THE REGION. LOOK FOR THIS SYSTEM TO CONTINUE TO DEEPEN WITHIN THE NEXT 24 HOURS...WHILE MOVING EASTWARD TO TAMPA FLORIDA WITH CONVECTION. THE COLD FRONT WILL EXTEND SOUTH FROM THE LOW CENTER TO THE YUCATAN PENINSULA. THE CARIBBEAN SEA... UPPER LEVEL FLAT RIDGE OF HIGH PRESSURE IS OVER THE ENTIRE CARIBBEAN BASIN. WATER VAPOR IMAGERY SHOWS STRONG SUBSIDENCE AND DRY AIR ALOFT ASSOCIATED WITH THIS SYSTEM...SUPPRESSING DEEP STRONG CONVECTION ACROSS THE REGION. BROKEN LOW CLOUDS ARE OVER THE NORTHERN CARIBBEAN NORTH OF 18N. OTHERWISE...MOSTLY FAIR WEATHER IS OVER THE REMAINDER OF THE CARIBBEAN SEA. MARINE OBSERVATIONS SHOW 10 TO 20 KT TRADEWINDS OVER MOST OF THE AREA. A COLD FRONT IS EXPECTED TO ENTER THE FAR NW BASIN WITH CONVECTION OVER THE NEXT 24 HOURS. OF SIGNIFICANCE...A LARGE VOLCANIC ERUPTION OCCURRED ON MONTSERRAT SOUFRIERE HILLS AT 1715 UTC THURSDAY. SATELLITE IMAGERY CONTINUES TO SHOW LAYERS OF VOLCANIC ASH FROM 14N TO 16N BETWEEN 60W AND 65W...INCLUDING THE ISLANDS OF GUADELOUPE AND DOMINICA. A VOLCANIC ASH ADVISORY HAS BEEN ISSUED FOR AVIATION INTERESTS. THE ATLANTIC OCEAN. A COLD FRONT ENTERS THE CENTRAL ATLANTIC NEAR 32N42W EXTENDING SOUTHWEST TO PUERTO RICO ALONG 27N45W 23N50W 21N55W 19N60W 18N65W. SCATTERED SHOWERS ARE WITHIN 60 NM EAST OF THE FRONT. GALE FORCE WINDS ARE ARE NORTH OF 28N WITHIN 350 NM ON EITHER SIDE OF THE FRONT. THIS SYSTEM IS FORECAST TO CONTINUE TO MOVE EASTWARD WITH MORE CONVECTION. THE TAIL END OF A DISSIPATING COLD FRONT IS OVER THE FAR EASTERN ATLANTIC FROM 32N13W TO 25N17W. STRONG SUBSIDENCE AND DRY AIR ALOFT IS ELSEWHERE SOUTH OF 20N. SATELLITE IMAGERY IS SHOWING MODERATE CONVECTION ENTERING THE FAR WESTERN ATLANTIC...FROM THE COAST OF SOUTH CAROLINA TO THE NORTHEAST FLORIDA COAST. THIS AREA OF CONVECTION IS RELATED TO A DEEP SURFACE LOW PRESSURE SYSTEM CURRENTLY OVER THE NORTHERN GULF OF MEXICO. FORECAST MODELS INDICATE A COLD FRONT MOVING ACROSS THE BAHAMAS AND GREATER ANTILLES OVER THE NEXT 24 HOURS...CREATING GALE FORCE WINDS NORTH OF 29N WEST OF THE FRONT TO 64W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE. $$ GARCIA