000 AXNT20 KNHC 101130 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST SUN FEB 10 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1130 UTC ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 7N12W 3N25W 1N34W 2N43W EQ. SCATTERED MODERATE CONVECTION IS WITHIN 60 NM OF LINE FROM 2N4W TO 2N8W. SMALL CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 150-180 NM OF THE AXIS BETWEEN 23W AND 35W. ...DISCUSSION... GULF OF MEXICO... RATHER FAST MID TO UPPER LEVEL FLOW EVIDENT ACROSS THE CONUS WITH SHORTWAVE TROUGHS SWEEPING EWD IN STRONG WLY FLOW ALOFT. THE MOST RECENT SHORTWAVE TROUGH EXTENDS FROM A VORT MAX CENTERED ABOUT 240 NM OFF THE MID-ATLANTIC COAST/38N72W SWWD TO A BASE OVER N FLORIDA AND THE ADJACENT NE GULF. MODERATE TO STRONG UPPER LEVEL SUBSIDENCE IS SWEEPING OFF THE SE COAST AND EXTENDS WWD ACROSS MUCH OF THE DEEP SOUTH AND NRN GULF IN THE WAKE OF THE TROUGH. THE TROUGH IS PROVIDING SUPPORT FOR A COLD FRONT EXTENDING FROM NEAR CEDAR KEY FLORIDA TO THE NE GULF NEAR 28N85W. THIS FRONT WAS MOVING SE AT 20 KT AND IS EXPECTED TO OVERTAKE A WEAKENING QUASI-STATIONARY FRONTAL TROUGH CURRENTLY EXTENDING ACROSS EXTREME S FLORIDA OVER THE UPPER KEYS TO THE SRN GULF NEAR 22N87W LATER TODAY. ALTHOUGH THE FRONTAL TROUGH APPEARS TO BE LOSING ITS DEFINITION SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE OCCURRING WITHIN 60-90 NM SE OF THE FRONT N OF 27N. THE HEAVIEST ACTIVITY WAS OCCURRING IN THE STRAITS OF FLORIDA BETWEEN MIAMI AND GRAND BAHAMA ISLAND AND ALSO NEAR THE N COAST OF CUBA. CARIBBEAN SEA... AN UPPER RIDGE EXTENDS ACROSS THE WRN CARIBBEAN FROM PANAMA TO HISPANIOLA AND CONTINUES NEWD INTO THE SUBTROPICAL ATLC. AN UPPER LEVEL TROUGH/SHEAR AXIS IS UNDERCUTTING THE RIDGE AND EXTENDS ACROSS THE NE WINDWARD ISLANDS NEAR GUADELOUPE WWD JUST TO THE S OF PUERTO RICO AND HISPANIOLA. AN EMBEDDED SMALL MID LEVEL CYCLONIC CIRCULATION WAS JUST S OF THE MONA PASSAGE NEAR 17N68W. CONFLUENT FLOW WITHIN THE SHEAR AXIS MANIFESTED ITSELF IN VERY STRONG UPPER LEVEL SUBSIDENCE OVER THE FAR NE PORTION OF THE WINDWARD ISLANDS AND PUERTO RICO WITH PRONOUNCED SUBSIDENCE NOTED ELSEWHERE OVER THE CARIBBEAN. THIS SUBSIDENCE WAS LIMITING ANY THUNDERSTORMS ACROSS THE AREA WITH THE EXCEPTION OF A SMALL CLUSTER OF ACTIVITY IN THE GULF OF HONDURAS NEAR ROATAN ISLAND. EXPANSIVE SURFACE RIDGE OVER THE ATLC COUPLED WITH THE LOWER PRESSURE OVER SOUTH AMERICA IS PRODUCING A RATHER TIGHT PRESSURE GRADIENT OVER THE SW CARIBBEAN RESULTING IN MODERATE/STRONG EASTERLY TRADE WINDS ACROSS THE AREA. A 0242 UTC ASCAT PASS INDICATED 25-30 KT WINDS ALONG THE COAST OF COLOMBIA. THE TRADE WINDS ARE USHERING IN SOME LOW LEVEL CLOUDS AND WIDELY SCATTERED LOW TOPPED SHOWERS. ATLANTIC OCEAN... THE UPPER LEVEL SHORTWAVE TROUGH MOVING OFF THE MID-ATLANTIC COAST IS PROVIDING SOME SUPPORT FOR AN EXISTING STATIONARY FRONT WHICH EXTENDS FROM 32N71W TO 27N77W WHERE IS BECOMES A DISSIPATING STATIONARY FRONT ACROSS EXTREME S FLORIDA AND THE UPPER KEYS. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 60 NM SE OF THE FRONT N OF 27N WITH MORE PRONOUNCED ACTIVITY OCCURRING IN THE STRAITS OF FLORIDA BETWEEN MIAMI AND GRAND BAHAMA ISLAND AND ALSO NEAR THE N COAST OF CUBA. THIS ACTIVITY WAS PROPAGATING SWD AT 15 KT. THE CENTRAL ATLC N OF 19N BETWEEN 40W AND 75W IS DOMINATED BY AN EXPANSIVE DEEP LAYERED RIDGE AND EMBEDDED ANTICYCLONE NEAR 24N60W. THE SURFACE RIDGE IS ANCHORED BY A 1024 MB HIGH NEAR 28N53W. AN UPPER LEVEL TROUGH OVER THE FAR E ATLC EXTENDS FROM AN UPPER LEVEL LOW N OF THE CANARY ISLANDS NEAR 32N15W ACROSS THE W COAST OF MAURITANIA AND WESTERN SAHARA THEN TURNS WSWWD THROUGH 20N22W 18N35W THEN UNDERCUTS THE RIDGE NOTED ABOVE THROUGH 18N50W TO THE NE WINDWARD ISLANDS. ASSOCIATED WEAKENING COLD FRONT EXTENDS FROM A 1008 MB LOW OVER GRAND CANARY ISLAND NEAR 28N16W ALONG 27N14W THEN SW ALONG 21N20W TO 20N22W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE N OF 29N FROM THE MAINLAND OF MOROCCO TO 35N BETWEEN 8W-14W. AN E/W UPPER RIDGE EXTENDS ACROSS THE TROPICAL ATLC ALONG 4N/5N TO 40W AND A WEAKENING JETSTREAM WITH WINDS OF 90 TO 110 KT IS ALONG THE N PERIPHERY OF THE RIDGE WITHIN 150 NM OF LINE FROM 14N35W TO INLAND OVER W AFRICA NEAR 19N16W/MAURITANIA. $$ COBB