000 AXNT20 KNHC 260003 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SAT JUL 25 2009 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 18N44W TO 6N40W MOVING W 15-20 KT. THIS WAVE IS ALONG THE LEADING EDGE OF A DEEP LAYER MOISTURE MAXIMUM AS OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY. VISIBLE SATELLITE IMAGERY INDICATES LOW LEVEL CYCLONIC CURVATURE MAINLY NEAR 12N43W. DRY SAHARAN AIR IS LIMITING DEEP CONVECTION NEAR THE WAVE. TROPICAL WAVE IS ALONG 83W S OF 21N MOVING NEAR W 20 KT. THIS WAVE IS EMBEDDED WITHIN A BROAD AREA OF DEEP LAYER MOISTURE MAXIMUM AS OBSERVED IN TOTAL PRECIPITABLE WATER IMAGERY. SUBSIDENCE. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS W OF THE WAVE AXIS OVER CENTRAL AMERICA FROM 11N-16N BETWEEN 83W-89W. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 14N16W 9N37W 11N54W 10N63W. ISOLATED MODERATE CONVECTION IS ALONG THE COAST OF WEST AFRICA FROM 8N-10N BETWEEN 14W-20W. SIMILAR CONVECTION IS FROM 8N-12N BETWEEN 28W-38W. SCATTERED MODERATE CONVECTION FROM 9N-12N BETWEEN 48W-51W. ...DISCUSSION... GULF OF MEXICO... A 1020 MB HIGH IS CENTERED OVER THE NE GULF OF MEXICO NEAR 28N87W. 5-10 KT ANTICYCLONIC SURFACE WINDS REMAIN OVER THE E GULF E OF 90W WHILE 5-10 KT SOUTHERLY WINDS ARE OVER THE W GULF. ELSEWHERE...PATCHES OF SCATTERED MODERATE CONVECTION HAVE ADVECTED OVER FLORIDA...THE YUCATAN PENINSULA...AND THE S GULF S OF 27N...FROM THE SW ATLANTIC AND W CARIBBEAN. THIS CONVECTION MAY BE ASSOCIATED WITH TROPICAL MOISTURE MOVING RAPIDLY WEST. IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS CENTERED OVER THE NW GULF NEAR 27N93W. UPPER LEVEL DIFFLUENCE SE OF THE CENTER IS HELPING TO PRODUCE CONVECTION OVER THE SE GULF AND FLORIDA. A SIGNIFICANT AMOUNT OF UPPER LEVEL MOISTURE COVERS THE GULF. EXPECT...LITTLE CHANGE OVER THE NEXT 24 HOURS. CARIBBEAN SEA... A TROPICAL WAVE IS OVER THE W CARIBBEAN. SEE ABOVE. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS ALSO OVER W CUBA FROM 21N-23N BETWEEN 78W-84W...AND OVER THE YUCATAN PENINSULA FROM 17N-21N BETWEEN 87W-91W. THE REMAINDER OF THE CARIBBEAN E OF 80W IS DOMINATED BY DRY AIR AND IS VOID OF CONVECTION. ISOLATED SHOWERS ARE HOWEVER OVER PUERTO RICO AND THE LEEWARD ISLANDS FROM 17N-20N BETWEEN 60W-67W. FRESH TO STRONG TRADEWINDS ARE OVER THE CARIBBEAN WITH THE STRONGEST WINDS UP TO 30 KT ARE NEAR THE COAST OF COLUMBIA. IN THE UPPER LEVELS...A SMALL UPPER LEVEL HIGH IS CENTERED OVER HONDURAS WHILE EASTERLY UPPER LEVEL FLOW AND STRONG SUBSIDENCE IS OVER THE CENTRAL AND E CARIBBEAN E OF 80W. EXPECT...TROPICAL MOISTURE WITH CONVECTION TO ADVECT OVER THE WINDWARD ISLANDS OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... SCATTERED MODERATE CONVECTION IS OVER THE N BAHAMAS FROM 23N-27N BETWEEN 76W-80W. A 1028 MB HIGH IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 33N37W. A RIDGE AXIS EXTENDS W TO E OF THE BAHAMAS NEAR 27N75W. A SURFACE TROUGH IS OVER THE CENTRAL ATLANTIC FROM 26N45W TO 18N49W. THIS TROUGH DELINEATES A SURGE OF TROPICAL MOISTURE THAT HAS BROKEN AWAY FROM THE TROPICAL WAVE FURTHER S. IN THE UPPER LEVELS...AN UPPER LEVEL RIDGE IS OVER THE W ATLANTIC W OF 70W. AN UPPER LEVEL LOW IS FURTHER E CENTERED NEAR 28N60W. A LARGE UPPER LEVEL HIGH IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 20N43W. ANOTHER UPPER LEVEL HIGH IS CENTERED OVER THE CANARY ISLANDS NEAR 28N12W. EXPECT...TROPICAL CONVECTION ALONG THE ITCZ...AND WITH THE TROPICAL WAVE OVER THE NEXT 24 HOURS. $$ FORMOSA