000 AXNT20 KNHC 221033 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT JUL 22 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. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 32W/33W S OF 20N MOVING W 15-20 KT. BROAD LOW LEVEL SIGNATURE CURVATURE IS OBSERVED ON INFRARED SATELLITE IMAGERY. WAVE IS EMBEDDED WITH AN AREA OF DENSE AFRICAN DUST... THUS NO ASSOCIATED SHOWERS/CONVECTION. TROPICAL WAVE IS ALONG 50W/51W S OF 18N MOVING W 10-15 KT. WEAK...NARROW LOW LEVEL SIGNATURE CURVATURE IS OBSERVED ON INFRARED SATELLITE IMAGERY. WAVE IS EMBEDDED WITH AN AREA OF DENSE AFRICAN DUST...THUS NO ASSOCIATED SHOWERS/CONVECTION. TROPICAL WAVE IS ALONG 65W/66W S OF 20N MOVING W 15-20 KT. WEAK BUT WELL-DEFINED LOW LEVEL SIGNATURE CURVATURE IS OBSERVED ON INFRARED SATELLITE IMAGERY. HOWEVER...DUE TO THE VERY DRY CONDITIONS...NO ASSOCIATED SHOWERS/CONVECTION. TROPICAL WAVE IS ALONG 93W S OF 21N MOVING W 15 KT. WAVE IS MOSTLY OVER S MEXICO AS WELL AS BEING BENEATH AN UPPER RIDGE WHICH IS MASKING THE SATELLITE IMAGERY. SCATTERED MODERATE/STRONG CONVECTION IS ACROSS THE BAY OF CAMPECHE S OF 21N. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 16N16W 10N26W 4N43W 5N56W AND JUST S OF PANAMA AND COSTA RICA IN THE E PACIFIC REGION. SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 175 NM N OF THE ITCZ AXIS FROM 43W-47W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 200 NM N OF THE AXIS FROM 17W-20W. CLUSTERS SCATTERED MODERATE CONVECTION ARE WITHIN 200 NM OF THE ITCZ AXIS FROM 22W-31W AND WITHIN 175 NM OF THE AXIS FROM 37W-42W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LOW IS IN THE E GULF NEAR 27N88W WITH AN UPPER TROUGH EXTEND W TO THE COAST OF TEXAS NEAR BROWNSVILLE. BROAD UPPER HIGH OVER THE TENNESSEE/NORTH CAROLINA BORDER EXTENDS S TO THE N GULF COAST AND A SECOND UPPER RIDGE COVERING THE S GULF S OF 24N W OF 85W ANCHORED OVER SW MEXICO. A WEAK UPPER RIDGE IN THE FAR W ATLC AND FROM OVER CUBA THROUGH THE STRAITS OF FLORIDA GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 28N E OF 85W ACROSS FLORIDA AND THROUGH THE STRAITS OF FLORIDA. DIFFLUENCE COUPLED WITH THE TROPICAL WAVE IS GENERATING THE CONVECTION OVER THE BAY OF CAMPECHE. CARIBBEAN SEA... BROAD UPPER RIDGE OVER THE S GULF EXTENDS INTO THE W CARIBBEAN W OF 85W WITH A WEAK UPPER RIDGE EXTENDING FROM THE CAYMAN ISLANDS ACROSS CUBA NEAR 23N81W INTO THE W ATLC. AN INDUCED UPPER LOW IS OVER THE CENTRAL CARIBBEAN ROUGHLY CENTERED NEAR 14N77W. A SECOND UPPER RIDGE COVERS THE SE CARIBBEAN S OF 16N E OF 73W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS OVER THE SW CARIBBEAN S OF 10N FROM COLOMBIA TO COSTA RICA DUE TO THE PROXIMITY OF THE ITCZ AXIS IN THE E PACIFIC REGION. STRONG TRADEWINDS CONTINUE ACROSS THE CARIBBEAN S OF 18N WITH GALE FORCE WINDS EXPECTED LATER IN THE WEEKEND. ATLANTIC OCEAN... A WEAK UPPER RIDGE EXTENDS FROM THE CAYMAN ISLANDS ACROSS CUBA NEAR 23N81W INTO THE W ATLC ALONG 27N71W TO AN UPPER HIGH NEAR 34N62W. AN UPPER LOW IS CENTERED N OF THE REGION NEAR 35N71W WITH AN UPPER TROUGH EXTENDING SW TO NE FLORIDA NEAR JACKSONVILLE. SCATTERED SHOWERS/THUNDERSTORMS ARE FROM 22N-30N W OF 70W TO OVER FLORIDA AND THROUGH THE STRAITS OF FLORIDA WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 29N FROM 66W-72W. A MID/UPPER LOW IS IN THE CENTRAL ATLC NEAR 29N42W WITH FLOW WITHIN 200 NM. BROAD UPPER RIDGE COVERS THE REMAINDER OF THE ATLC EXTENDING FROM OFF AFRICA NEAR 20N16W ALONG 17N38W TO 16N46W. BROAD SURFACE RIDGE DOMINATES THE ATLC GIVING THE ATLC E OF 70W IS SUPPORTING LITTLE IN THE WAY OF CLOUDS MUCH LESS SHOWERS. LARGE AREA OF DENSE SAHARAN DUST CONTINUES TO MOVE OFF THE COAST OF AFRICA S OF 26N E OF 57W. $$ WALLACE