000 AXNT20 KNHC 221720 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN JUL 22 2007 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 1645 UTC. ...TROPICAL WAVES... TROPICAL WAVE OVER THE CAPE VERDE ISLANDS ALONG 25W/26W S OF 18N MOVING W 10-15 KT. THE WAVE IS FAIRLY WELL ORGANIZED WITH CYCLONIC TURNING COVERING A BROAD AREA. A 1011 MB SFC LOW HAS BE ADDED ALONG THE WAVE AXIS NEAR 13N. CONVECTION IS CONFINED TO THE ITCZ FROM 10N-13N BETWEEN 21W-27W. TROPICAL WAVE OVER THE LESSER ANTILLES ALONG 61W/62W S OF 20N MOVING W NEAR 15 KT. BROAD LOW LEVEL INVERTED-V SIGNATURE IS NOTED ON SATELLITE IMAGERY. SCATTERED MODERATE CONVECTION IS FROM 15N-18N BETWEEN 59W-66W. MOISTURE FROM THIS WAVE SHOULD AFFECT THE UK/US VIRGIN ISLANDS AND PUERTO RICO LATE TODAY THROUGH MONDAY. TROPICAL WAVE IS IN THE CARIBBEAN ALONG 81W S OF 21N MOVING W NEAR 15 KT. A LOW LEVEL INVERTED-V SIGNATURE IS NOTED. A CLUSTER OF MODERATE TO STRONG CONVECTION IS FROM 13N-16N BETWEEN 79W-83W. THE WAVE WILL MOVE ACROSS CENTRAL AMERICA AND THE NW CARIBBEAN TODAY...REACHING THE YUCATAN PENINSULA AND BELIZE MONDAY MORNING. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 14N16W 12N20W 10N30W 8N50W 11N58W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 10N-13N BETWEEN 20W-27W. ...DISCUSSION... GULF OF MEXICO... A WEAK STATIONARY FRONT EXTENDS FROM A 1013 MB SFC LOW IN THE WESTERN ATLANTIC...ACROSS NORTHERN FLORIDA...ALONG THE NE GULF COAST AND INTO LOUISIANA. A LINE OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS EXTENDS 80-100 NM INTO THE NORTHERN GULF WATERS AHEAD OF THE FRONT WITH A SECOND LINE OF SHOWERS AND THUNDERSTORMS SURROUNDING A PRE-FRONTAL TROUGH THAT STRETCHES FROM THE FLORIDA PANHANDLE SW TO NEAR 25N87W. THE FRONT IS EXPECTED TO DRIFT SOUTH TONIGHT AND MONDAY BEFORE GRADUALLY DISSIPATING. A DEEP LAYERED TROUGH OVER THE EASTERN U.S. EXTENDS ACROSS FLORIDA TO AN UPPER LOW NEAR 21N95W. THIS TROUGH IS HELPING TO GENERATE SHOWERS AND TSTMS OVER FLORIDA PENINSULA AND ACROSS THE STRAITS OF FLORIDA. A BROAD UPPER LEVEL HIGH IS INLAND OVER NW MEXICO WITH THE UPPER RIDGE COVERING THE FAR WEST GULF. A WEAK PRES PATTERN WILL CONTINUE TO DOMINATE THE GULF THROUGH TUE PROVIDING LIGHT WINDS ACROSS THE REGION. CARIBBEAN SEA... THE PRES GRADIENT BETWEEN THE ATLANTIC RIDGE AND THE LOW PRES OVER COLOMBIA IS PRODUCING MODERATE TRADE WINDS OF 15 TO 20 KT ACROSS THE SOUTH-CENTRAL CARIBBEAN. A TROPICAL WAVE ALONG 81W IS PRODUCING CONVECTION IN THE CENTRAL CARIBBEAN. SEE TROPICAL WAVE SECTION ABOVE. A CLUSTER OF MODERATE CONVECTION FROM A 1012 MB LOW OVER COLOMBIA IS MOVING INTO THE SOUTHERN CARIBBEAN S OF 13N BETWEEN 74W-77W. ALOFT...AN UPPER LEVEL HIGH CENTERED SOUTH OF JAMAICA IS ENHANCING THE CONVECTION RELATED TO THE TROPICAL WAVE WHILE ANOTHER UPPER LEVEL HIGH IS OVER THE NE CARIBBEAN SUPPORTING THE CONVECTION ASSOCIATED WITH THE WAVE CURRENTLY OVER THE LEEWARD ISLANDS. BETWEEN THE TWO WAVES...MODERATE SUBSIDENCE IS PROVIDING RELATIVELY CLEAR SKIES. ATLANTIC OCEAN... A BROAD BAND OF SCATTERED SHOWERS AND THUNDERSTORMS SURROUNDS THE FRONTAL BOUNDARY THAT EXTENDS FROM A 1013 MB SFC LOW CENTERED IN THE WEST ATLC NEAR 34N73W. FURTHER EAST...AN UPPER LEVEL LOW CENTERED NEAR 34N65W IS GENERATING A LINE OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THAT EXTENDS FROM 32N61W SW TO 24N71W. TWO LOW LEVEL CIRCULATION CENTERS EXIST BELOW THIS UPPER LEVEL SYSTEM...THE FIRST IS JUST EAST OF BERMUDA...AND THE SECOND IS AT THE FAR SOUTH END NEAR 25N70W. A LARGE CLUSTER OF MODERATE TO STRONG CONVECTION BETWEEN 24N-27N AND 67W-71W APPEARS TO BE ASSOCIATED WITH THE SOUTHERN CIRCULATION CENTER. THE REMAINDER OF THE ATLANTIC IS UNDER THE INFLUENCE OF A STRONG 1034 MB SFC HIGH ANCHORED NEAR 39N42W. ONLY PATCHES OF LOW/MID CLOUDS ARE SEEN UNDER THE INFLUENCE OF THIS SYSTEM. PRES GRADIENT BETWEEN THE HIGH AND A BROAD AREA OF LOW PRES ASSOCIATED WITH A TROPICAL WAVE IS PRODUCING A AREA OF 20 TO 25 KT NELY WINDS FROM 20N TO 30N EAST OF 45W. $$ WADDINGTON