000 AXNT20 KNHC 251057 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE JUL 25 2006 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN 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...WEATHER OBSERVATIONS...RADAR... AND METEOROLOGICAL ANALYSIS. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...SPECIAL FEATURES... A 1009 MB SURFACE LOW IS CENTERED ALONG THE COAST OF MEXICO BETWEEN TAMPICO AND BROWNSVILLE TEXAS DRIFTING NORTHWARD. SURFACE LOW IS BENEATH A BROAD UPPER RIDGE AIDING IN THE GENERATION OF SCATTERED MODERATE/STRONG CONVECTION IN THE NW GULF WITHIN 120 NM OF LINE FROM 27N92W TO THE SURFACE LOW NEAR 24N98W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS COVER THE REMAINDER OF THE AREA W OF 90W. UPPER-LEVEL WINDS ARE EXPECTED TO BECOME A LITTLE MORE FAVORABLE IF THE SURFACE LOW REMAINS OFFSHORE OR ALONG THE COAST IN WHICH CASE A TROPICAL DEPRESSION COULD DEVELOP. EVEN IF THE SYSTEM DOES NOT DEVELOP IT WILL STILL PRODUCE LOCALLY HEAVY RAINS TO NE MEXICO AND S TEXAS. ...TROPICAL WAVES AND TROPICAL LOWS... THE 1010 MB LOW IS NOW LONGER DISCERNIBLE ALONG THE COAST OF SENEGAL...HOWEVER A TROPICAL WAVE IS NOW ANALYZED OFF THE COAST ALONG 19W/20W S OF 19N MOVING W 15-20 KT. NO ASSOCIATED DEEP CONVECTION. TROPICAL WAVE IS ALONG 48W S OF 26N WITH A 1010 MB LOW ALONG THE WAVE NEAR 13N MOVING W 15 KT. WELL-DEFINED SIGNATURE CURVATURE WITH A EQUALLY WELL DEFINED LOW LEVEL CENTER OBSERVED ON INFRARED SATELLITE IMAGERY. THIS WAVE IS AT THE LEADING EDGE OF THE LATEST SURGE OF AFRICAN DUST. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 13N-23N BETWEEN 47W-53W. TROPICAL WAVE IS ALONG 70W/71W S OF 18N MOVING W 10-15 KT. WEAK EMBEDDED WITHIN AN AREA OF THINNING AFRICAN DUST LIMITING ANY SHOWER ACTIVITY TO ISOLATED SHOWERS FROM 17N-20N BETWEEN 69W-71W. TROPICAL WAVE IS ALONG 82W/83W S OF 16N MOVING W 10-15 KT. WEAK WAVE WITH NO ASSOCIATED DEEP CONVECTION. CONVECTION NEAR THE WAVE IS ASSOCIATED WITH THE ITCZ AXIS. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 12N13W 6N32W 13N51W 9N62W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS OFF THE COAST OF W AFRICA FROM 8N-11N E OF 16W TO THE COAST OF AFRICA AND WITHIN 160 NM OF THE AXIS FROM 34W-40W. CLUSTERS OF SCATTERED MODERATE CONVECTION DOT THE AREA WITHIN 150 NM OF THE AXIS ACROSS THE REMAINDER AXIS. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE COVERS THE W GULF W OF 90W ANCHORED BY AN UPPER HIGH LOCATED OVER SW MEXICO. THE 1009 MB LOW IN THE SPECIAL FEATURES SECTION IS EMBEDDED BENEATH THIS UPPER RIDGE. AN UPPER HIGH IS OFF THE SE US COAST IN THE W ATLC WITH THE UPPER RIDGE EXTENDING ACROSS FLORIDA NEAR TAMPA TO THE CENTRAL GULF NEAR 25N87W. ISOLATED SHOWERS HAVE DEVELOPED OVER THE FLORIDA KEYS. THE SURFACE RIDGE FROM THE W ATLC EXTENDS ACROSS FLORIDA TO THE CENTRAL GULF. CARIBBEAN SEA... TWO WEAK TROPICAL WAVES ARE IN THE CARIBBEAN SEA. THE UPPER RIDGE THAT EXTENDS FROM AN UPPER HIGH IN THE W ATLC DIPS INTO THE NW CARIBBEAN N OF 20N W OF 78W. BROAD UPPER LOW COVERS THE CENTRAL CARIBBEAN CENTERED NEAR 16N78W WHILE AND UPPER RIDGE EXTENDS ACROSS THE LESSER ANTILLES TO OVER THE E CARIBBEAN. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS S OF 10N FROM COLOMBIA TO COSTA RICA IS DUE TO THE CLOSE PROXIMITY OF THE ITCZ AXIS IN THE E PACIFIC REGION. REMAINDER OF THE CARIBBEAN REMAINS CLEAR DUE TO DRY AIR AND THE PRESENCE OF DIMINISHING AFRICAN DUST. STRONG TRADEWINDS COVER THE CARIBBEAN S OF 18N WITH GALE FORCE WINDS OFF THE COAST OF COLOMBIA. ATLANTIC OCEAN... AN UPPER HIGH IS CENTERED OFF THE SE US NEAR 30N79W WITH AN UPPER RIDGE EXTENDING SW ACROSS FLORIDA NEAR DAYTONA BEACH INTO THE GULF OF MEXICO AND DIPPING INTO THE NW CARIBBEAN. SCATTERED THUNDERSTORMS ARE N OF 28N FROM 76W-80W. AN UPPER LOW IS IN THE CENTRAL ATLC NEAR 26N51W COVERING THE AREA FROM 21N-31N BETWEEN 45W-60W. BROAD UPPER HIGH IS IN THE W TROPICAL ATLC NEAR 15N57W COVERING THE AREA S OF 22N W OF 40W TO OVER THE CARIBBEAN. THE E ATLC IS DOMINATED BY AN UPPER RIDGE EXTENDING OFF THE COAST OF AFRICA NEAR 24N15W SW TO 20N40W. AT THE SURFACE...A BROAD RIDGE COVERS THE ATLC N OF 20N EXTENDING INTO THE GULF OF MEXICO ANCHORED BY A 1026 MB HIGH N OF THE REGION. A STRONG SURGE OF AFRICAN DUST COVERS THE THE E ATLC S OF 27N FROM THE CAPE VERDE ISLANDS TO THE TROPICAL WAVE NEAR 48W...THUS LIMITING CLOUDS OVER THAT AREA. WITH THE DRY AIR ALREADY IN PLACE OVER THE REMAINDER OF THE ATLC...NO OTHER SIGNIFICANT WEATHER IS IN THE ATLC. $$ WALLACE