000 AXNT20 KNHC 211032 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON AUG 21 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 35W/36W S OF 17N MOVING W 10-15 KT. BROAD MID LEVEL ROTATION IS OBSERVED ON INFRARED SATELLITE IMAGERY ALONG THE ITCZ. CONVECTION IS CONFINED TO WITHIN THE ITCZ AREA. TROPICAL WAVE IS ALONG 52W/53W S OF 19N MOVING W NEAR 15-20 KT. WELL DEFINED INVERTED-V CURVATURE IS OBSERVED ON INFRARED SATELLITE IMAGERY. SCATTERED MODERATE/STRONG CONVECTION IS FROM 8N-14N BETWEEN 34W-39W. TROPICAL WAVE IN THE E CARIBBEAN IS ALONG 70W S OF 18N MOVING W 10-15 KT. WAVE IS BENEATH THE E EDGE OF AN UPPER RIDGE WITH ONLY ISOLATED SHOWERS FROM 15N-18N BETWEEN 67W-72W. TROPICAL WAVE IN THE W CARIBBEAN IS ALONG 85W S OF 18N MOVING W 10-15 KT. WAVE IS MOSTLY INLAND OVER CENTRAL AMERICA AND ALONG AND BENEATH AN UPPER RIDGE MASKING THE CLASSIC SATELLITE SIGNATURE. NO ASSOCIATED SHOWERS/CONVECTION. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 14N16W 7N25W 9N34W 8N40W 12N55W 10N62W ACROSS THE N PORTION OF SOUTH AMERICA AND PANAMA INTO THE E PACIFIC REGION. A TROPICAL WAVE IS ALONG THE COAST OF AFRICA WITH A BROAD MID LEVEL ROTATION OBSERVED ON INFRARED SATELLITE IMAGERY BUT WAS NOT ANALYZED AS SUCH DUE TO THE LACK OF SUPPORTING SURFACE AND UPPER AIR DATA. SCATTERED MODERATE TO STRONG CONVECTION COVERING THE AREA FROM 9N-15N BETWEEN 18W-22W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE WITHIN 120/150 NM OF THE ITCZ AXIS FROM 16W-24W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 120/150 NM OF THE AXIS FROM 41W-62W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE ANCHORED OVER NE TEXAS EXTENDS OVER THE N GULF N OF 27N. AN UPPER TROUGH EXTENDS ACROSS THE S GULF FROM THE SW COAST OF FLORIDA NEAR NAPLES TO AN UPPER LOW ALONG THE COAST OF MEXICO JUST BETWEEN TAMPICO AND VERACRUZ PROVIDING ENOUGH DIFFLUENCE OVER THE S GULF TO GENERATE CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE AREA S OF A LINE FROM NEAR TAMPA FLORIDA TO THE COAST OF MEXICO JUST N OF TAMPICO. CARIBBEAN SEA... BROAD UPPER RIDGE EXTENDS ACROSS THE CARIBBEAN FROM NICARAGUA/ HONDURAS BORDER ALONG 16N77W ACROSS HISPANIOLA INTO THE W ATLC. THIS IS PROVIDING ENOUGH DIFFLUENCE OVER W CARIBBEAN TO GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF A LINE FROM THE PANAMA/COSTA RICA BORDER NW TO THE WINDWARD PASSAGE WITH THE SCATTERED MODERATE/STRONG CONVECTION FROM 14N-18N BETWEEN 78W-82W. SCATTERED STRONG CONVECTION IS S OF 10N W OF 79W TO INLAND OVER COLOMBIA AND E PANAMA ASSOCIATED WITH THE ITCZ AXIS THAT EXTENDS ALONG 8N ACROSS THAT AREA. MODERATE/STRONG TRADEWINDS ARE ACROSS THE AREA. ATLANTIC OCEAN... SMALL UPPER LOW IS IN THE W ATLC CENTERED NEAR 29N80W AND IS GENERATING THE SCATTERED SHOWERS/THUNDERSTORMS FROM 23N-29N BETWEEN 75W-80W. AN UPPER LOW REMAINS SE OF BERMUDA NEAR 31N62W WITH AN ASSOCIATED SURFACE TROUGH EXTENDING FROM 22N67W-29N64W. HOWEVER...WITH DRY AIR IN PLACE THIS FEATURE IS ONLY ABLE TO GENERATE SCATTERED SHOWERS FROM 22N-28N BETWEEN 60W-68W. THE UPPER RIDGE EXTENDS FROM THE CARIBBEAN ACROSS HISPANIOLA TO NEAR 24N66W IN THE W ATLC. THE REMAINDER OF THE ATLC IS DOMINATED BY MOSTLY BENIGN FEATURES WHICH INCLUDE AN UPPER LOW NEAR 23N42W AND AN UPPER HIGH NEAR 27N24W BUT WITH DRY AIR IN PLACE OVER THE E ATLC NO SIGNIFICANT CLOUDS OR SHOWERS ARE ASSOCIATED WITH THESE FEATURES. A SURFACE RIDGE DOMINATES THE MUCH ATLC WITH THE SURFACE HIGHS N OF THE REGION. SIGNIFICANT AMOUNTS OF AFRICA DUST COVER THE E TROPICAL ATLC FROM THE ITCZ TO 24N BETWEEN THE CAPE VERDE ISLANDS TO 55W WITH CLEARING E OF THE ISLANDS. $$ WALLACE