000 AXNT20 KNHC 220545 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT FRI JUN 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0445 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 34W S OF 13N MOVING W 15 KT. WAVE HAS WEAKENED OVER THE PAST 24 HOURS WITH THE SCATTERED SHOWERS 120 NM OF THE AXIS FROM 4N-9N. TROPICAL WAVE IS ALONG 46W S OF 13N MOVING W 15 KT. WEAK LOW LEVEL INVERTED-V CURVATURE IS OBSERVED ON SATELLITE IMAGERY. CONVECTION IS EMBEDDED WITHIN THE ITCZ. CENTRAL CARIBBEAN TROPICAL WAVE IS ALONG 73W S OF 20N MOVING W NEAR 10 KT. THIS WAVE HAS BEEN DIFFICULT TO TRACK AS IT HAS MOVED THROUGH SOME VERY DRY AIR AND IT IS BELIEVED THAT IT IS ACTUALLY FURTHER WEST. UPPER LEVEL RIDGE IS ADVECTING UPPER MOISTURE ACROSS HISPANIOLA PRODUCING ONLY ISOLATED SHOWERS...THEREFORE THIS WAVE WILL BE DROPPED AT 0600 UTC. W CARIBBEAN TROPICAL WAVE REMAINS ALONG 81W/82W S OF 19N WITH A 1009 MB LOW ALONG THE WAVE NEAR 11N. BROAD AREA OF LOW/MID LEVEL ROTATION IS OBSERVED ON SATELLITE IMAGERY EXTENDING TO OVER THE CAYMAN ISLANDS. UPPER LEVEL RIDGE IS ADVECTING UPPER MOISTURE ACROSS THE AREA ENHANCING SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 90/120 NM OF LINE FROM 14N79W TO 19N84W AND SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE REMAINDER OF THE AREA S OF 20N BETWEEN 77W-85W. IT IS EXPECTED THE THE WAVE WILL CONTINUE TO MOVE W WHILE THE LOW BEGINS TO DISSIPATE. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 8N12W 7N19W 8N28W 7N38W 7N45W 6N56W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 2N-9N BETWEEN 36W-48W...WITHIN 120 NM S OF THE AXIS FROM 10W-19W...AND WITHIN 120 NM N OF THE AXIS FROM 48W-54W. ...DISCUSSION... GULF OF MEXICO... AN UPPER RIDGE EXTENDS FROM AN UPPER HIGH OVER SW MEXICO ACROSS THE W GULF TO THE LOWER MISSISSIPPI VALLEY COVERING THE AREA W OF 90W. A SECOND UPPER RIDGE EXTENDS FROM THE W CARIBBEAN OVER THE SE GULF INDUCING AN UPPER TROUGH EXTENDING FROM OVER THE FLORIDA PANHANDLE TO THE YUCATAN PENINSULA. AT THE SURFACE...A SMALL 1012 MB LOW REMAINS ALONG THE NE FLORIDA COAST WITH A SURFACE TROUGH EXTENDING ACROSS CENTRAL FLORIDA TO 26N86W INT HE E GULF GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE FAR E GULF. THE UPPER RIDGE OVER MEXICO IS ADVECTING MOISTURE WITH SIMILAR ACTIVITY OVER THE FAR W GULF FROM 20N-29N W OF 95W. A SURFACE RIDGE REMAINS OVER THE MISSISSIPPI VALLEY INTO THE NW GULF WITH A 1018 MB HIGH ALONG THE LOUISIANA COAST. CARIBBEAN SEA... BROAD UPPER RIDGE EXTENDS FROM A ILL-DEFINED UPPER HIGH LOCATED OFF THE COAST OF NICARAGUA N OVER CUBA AND COVERING THE W CARIBBEAN W OF 74W WITH NEAR ZONAL WESTERLY FLOW OVER THE REMAINDER PORTION OF THE CARIBBEAN. THIS UPPER FEATURE IS ALSO ADVECTING COPIOUS AMOUNTS OF TROPICAL MOISTURE ACROSS THE AREA ENHANCING SHOWER ACTIVITY AND CONVECTION ASSOCIATED WITH THE TROPICAL WAVE/LOW. THE E CARIBBEAN E OF 75W REMAINS CLOUD AND SHOWER FREE WITH THE EXCEPTION OF SOME ISOLATED SHOWERS OVER THE GREATER ANTILLES WITH STRONG EASTERLY TRADE WINDS ACROSS THE REGION. ATLANTIC OCEAN... A DEEP LAYERED TROUGH IS OVER THE NE US MOVING ACROSS THE NW ATLC EXTENDING A FRONTAL BOUNDARY ALONG 32N69W BECOMING NEAR STATIONARY NEAR 31N76W TO THE GEORGIA COAST. A WEAK 1012 MB LOW IS ALONG THE NE FLORIDA COAST NEAR JACKSONVILLE WITH A SURFACE TROUGH EXTENDING S ACROSS CENTRAL FLORIDA INTO THE E GULF OF MEXICO. HEAVY SHOWERS/THUNDERSTORMS ARE FROM OFF THE E COAST OF FLORIDA FROM 27N-30N BETWEEN 77W-80W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS POSSIBLE N OF 24N W OF 75W TO JUST INLAND OVER THE FLORIDA PENINSULA. A SECOND EVEN WEAKER UPPER TROUGH EXTENDS INTO THE W ATLC THROUGH 32N56W TO JUST E OF THE BAHAMAS NEAR 22N67W. BETWEEN THESE UPPER TROUGHS IS AN UPPER RIDGE ENHANCING SCATTERED SHOWERS/THUNDERSTORMS FROM 22N-27N BETWEEN 55W-68W. AN UPPER TROUGH IS OVER THE N/CENTRAL ATLC N OF THE REGION GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 90/120 NM OF A REMNANT FRONTAL TROUGH THAT EXTENDS IN THE REGION THROUGH 32N41W TO 26N48W. THE E ATLC IS DOMINATED BY AN UPPER HIGH AND A SURFACE RIDGE ANCHORED BY A 1030 MB HIGH JUST SE OF THE AZORES. THE COMBINATION OF THIS SURFACE RIDGE ALONG WITH DRY STABLE AIR ALOFT ASSOCIATED WITH AN UPPER RIDGE IS PROVIDING TRANQUIL CONDITIONS ACROSS THE REMAINDER OF THE ATLC. $$ WALLACE