000 AXNT20 KNHC 181044 TWDAT TROPICAL WEATHER DISCUSSION... NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT FRI APR 18 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 1015 UTC. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 3N7W 4N18W 2N32W 3N39W CROSSING THE EQUATOR NEAR 51W. CLUSTERS OF SCATTERED STRONG CONVECTION ARE FROM THE EQUATOR TO JUST INLAND OVER LIBERIA AFRICA BETWEEN 6W-9W WITH SCATTERED CLUSTERS OF SIMILAR CONVECTION WITHIN 90/120 NM OF THE ITCZ AXIS FROM 12W-16W. SCATTERED MODERATE/ ISOLATED STRONG CONVECTION IS WITHIN 90 NM N OF THE ITCZ AXIS FROM 21W-24W. CLUSTERS SCATTERED MODERATE CONVECTION ARE FROM 5N TO S OF THE EQUATOR W OF 37W TO INLAND OVER SOUTH AMERICA. NUMEROUS STRONG CONVECTION IS FROM THE EQUATOR TO INLAND OVER AFRICA E OF THE PRIME MERIDIAN. ...DISCUSSION... GULF OF MEXICO... UPPER RIDGE ANCHORED IN THE E PACIFIC REGION COVERS THE GULF AND INTO THE W ATLC WITH THE AXIS EXTENDING FROM THE YUCATAN PENINSULA NE TO ALONG E US COAST PROVIDING MODERATE SUBSIDENCE AND RATHER DRY AIR OVER THE GULF. A SURFACE RIDGE IS SHIFTING EASTWARD COVERING THE E GULF ANCHORED BY A 1023 MB HIGH IN THE W ATLC. RETURN SOUTHERLY FLOW AROUND THE SURFACE RIDGE IS BANKING LOW LEVEL ALONG THE COAST OF TEXAS AND LOUISIANA AHEAD OF A COLD FRONT THAT IS MOVING ACROSS E TEXAS. THIS FRONT AND THE ASSOCIATED DEEP LAYERED TROUGH WILL MOVE INTO THE GULF LATER TODAY DISSIPATING OVER THE E GULF SAT INTO SUN. SCATTERED SHOWERS/THUNDERSTORMS ASSOCIATED WITH THIS FRONT ARE ALONG THE IMMEDIATE TEXAS COAST AND WILL CONTINUE TO PROGRESS EASTWARD FOR THE NEXT SEVERAL HOURS. OTHERWISE THE REMAINDER OF THE GULF REMAINS RELATIVELY QUIET THIS MORNING. CARIBBEAN SEA... THE DEEP LAYERED TROUGH FROM THE W ATLC DIPS OVER HISPANIOLA WITH THE ASSOCIATED STATIONARY FRONT EXTENDING FROM THE W ATLC TO OVER HISPANIOLA. UPPER WESTERLY FLOW DOMINATES THE REMAINDER OF THE CARIBBEAN. STRONG NE TO E TRADE WINDS ARE ACROSS THE CARIBBEAN WITH THE HIGHEST WINDS ALONG THE COAST OF COLOMBIA. THESE TRADE WINDS COUPLED WITH THE REMNANTS OF THE FRONTAL BOUNDARY ARE BANKING LOW CLOUDS WITH ISOLATED SHOWERS NW OF A LINE FROM HISPANIOLA S OF JAMAICA TO NE HONDURAS. CONVERGENCE OF THE UPPER LEVEL WINDS AND SURFACE FLOW OVER THE SW CARIBBEAN IS GENERATING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 60 NM ALONG THE COAST OF PANAMA AND COST RICA S OF 11N W OF 80W. OTHERWISE THE CARIBBEAN REMAINS RELATIVELY CLEAR THIS MORNING. ATLANTIC OCEAN... BROAD DEEP LAYERED TROUGH COVERS THE W ATLC FROM 58W TO THE E COAST OF FLORIDA WITH THE MAIN UPPER LOW WELL N OF THE REGION. AT THE SURFACE...A STATIONARY FRONT ENTERS THE REGION E OF BERMUDA NEAR 32N59W TO OVER HISPANIOLA NEAR 19N71W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 90 NM EITHER SIDE OF THE FRONT N OF 20N WITH SCATTERED SHOWERS W OF THE FRONT WITHIN 90 NM OF LINE FROM 24N68W ACROSS THE TURKS AND CAICOS TO THE WINDWARD PASSAGE. A WEAK SURFACE TROUGH EXTENDS FROM 32N66W SW TO 26N72W. DEEP LAYERED RIDGE IS SHIFTING FROM THE US AND E GULF OF MEXICO COVERING THE FAR W ATLC W OF 78W WITH THE SURFACE RIDGE ANCHORED BY A 1023 MB HIGH NEAR 31N78W. BROAD DEEP LAYERED RIDGE COVERS THE REMAINDER OF THE ATLC WITH THE UPPER RIDGE ANCHORED NEAR 26N39W AND THE SURFACE 1031 MB HIGH ANCHORED NEAR 33N43W. AN DEEP LAYERED TROUGH IS MOVING S OVER THE NE ATLC TO 29N BETWEEN THE CANARY ISLANDS AND 30W WITH THE ASSOCIATED COLD FRONT N OF THE REGION. THE TYPICAL E/W UPPER RIDGE ACROSS THE TROPICS REMAINS TO THE S GENERATING A SHEAR AXIS EXTENDING 14W. THUS THE ATLC E OF 58W HAS FAIR WEATHER AGAIN THIS MORNING. $$ WALLACE