000 AXNT20 KNHC 272350 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT MON JUL 27 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... A TROPICAL WAVE IS INTRODUCED ALONG 18W S OF 18N MOVING W NEAR 20 KT. THIS WAVE COINCIDES WITH A BROAD MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. SCATTERED SHOWERS ARE WITHIN 120 NM OF THE WAVE AXIS. AN UNRELATED 1010 MB LOW HAPPENS TO BE W OF THE WAVE AXIS NEAR 18N22W. NO SIGNIFICANT CONVECTION OR SHOWERS ARE ASSOCIATED WITH THIS LOW. A TROPICAL WAVE IS ALONG 44W S OF 16N MOVING W NEAR 20 KT. THIS WAVE COINCIDES WITH A BROAD MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. ALSO...RECENT SATELLITE IMAGERY INDICATES CYCLONIC MOTION OF LOW LEVEL CLOUDS NEAR THIS WAVE. ISOLATED MODERATE CONVECTION IS FROM 10N-12N BETWEEN 42W-45W. A TROPICAL WAVE IS ALONG 68W S OF 19N MOVING W NEAR 25 KT. THIS WAVE COINCIDES WITH A WELL-DEFINED MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. VISIBLE SATELLITE IMAGERY INDICATES AN INVERTED-V PATTERN OF LOW LEVEL CLOUDS. STABLE ATMOSPHERIC CONDITIONS ASSOCIATED WITH AN UPPER LEVEL RIDGE ARE INHIBITING DEEP CONVECTION NEAR THIS WAVE. HOWEVER...SCATTERED SHOWERS ARE FROM 14N-17N BETWEEN 66W-70W. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 12N15W 12N21W 10N30W 11N44W 9N60W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS FROM 10N-13N BETWEEN 21W-24W...AND FROM 11N-12N BETWEEN 26W-28W. SCATTERED MODERATE CONVECTION IS FROM 9N-10N BETWEEN 34W-35W. ...DISCUSSION... GULF OF MEXICO... WEAK SURFACE RIDGING IS OVER THE GULF OF MEXICO WITH RIDGE AXIS ALONG 30N. 10-15 KT S WINDS ARE OVER THE W GULF W OF 90W WHILE 5-10 KT E-SE WINDS ARE OVER THE E GULF. PATCHES OF WIDELY SCATTERED MODERATE CONVECTION ARE OVER THE S GULF...FLORIDA... AND W CUBA. ELSEWHERE PREFRONTAL ACTIVITY IS PRODUCING SCATTERED MODERATE CONVECTION ALONG THE COASTS OF E TEXAS AND LOUISIANA FROM 29N-32N BETWEEN 89W-95W MOVING E. IN THE UPPER LEVELS...AN UPPER LEVEL LOW IS CENTERED OVER THE SW GULF NEAR 23N96W. AN UPPER LEVEL TROUGH IS OVER THE NE GULF N OF 25N AND E OF 90W. A SIGNIFICANT AMOUNT OF UPPER LEVEL MOISTURE COVERS THE ENTIRE GULF...FLORIDA...AND W CUBA. EXPECT...MORE CONVECTION OVER THE E GULF E OF 90W...FLORIDA...AND W CUBA...OVER THE NEXT 24 HOURS. CARIBBEAN SEA... FRESH TO STRONG TRADEWINDS ARE OVER THE CARIBBEAN WITH THE STRONGEST WINDS UP TO 30 KT NEAR THE COAST OF COLUMBIA. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS OVER THE S COAST OF CUBA W OF 77W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS ALSO OVER NW COLOMBIA FROM 7N-9N BETWEEN 74W-78W. A TROPICAL WAVE IS OVER THE E CARIBBEAN ALONG 68W. SEE ABOVE. THE REMAINDER OF THE CARIBBEAN IS DOMINATED BY DRY AIR AND IS VOID OF CONVECTION. IN THE UPPER LEVELS...A SMALL UPPER LEVEL HIGH IS CENTERED OVER W CUBA NEAR 22N82W. EASTERLY UPPER LEVEL FLOW IS OVER THE CENTRAL CARIBBEAN BETWEEN 70W-80W. THE BASE OF AN UPPER LEVEL TROUGH IS OVER THE E CARIBBEAN E OF 70W. STRONG SUBSIDENCE IS OVER THE CENTRAL AND W CARIBBEAN W OF 70W FROM 11N-20N. EXPECT...MORE CONVECTION OVER THE SOUTHERN AND WESTERN CARIBBEAN OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... ISOLATED MODERATE CONVECTION IS OVER THE N BAHAMAS AND W ATLANTIC FROM 24N-31N BETWEEN 75W-80W. A 1029 MB HIGH IS CENTERED OVER THE CENTRAL ATLANTIC NEAR 33N54W PRODUCING MOSTLY FAIR WEATHER. A RIDGE AXIS EXTENDS W TO N FLORIDA NEAR 30N82W. IN THE UPPER LEVELS...AN UPPER LEVEL TROUGH IS OVER THE W ATLANTIC W OF 75W. AN UPPER LEVEL RIDGE IS FURTHER E N OF 20N BETWEEN 65W-75W. AN UPPER LEVEL LOW IS CENTERED NEAR 32N57W. A LARGE UPPER LEVEL HIGH IS CENTERED NE OF THE LEEWARD ISLANDS NEAR 22N57W. ANOTHER UPPER LEVEL HIGH IS CENTERED OVER THE CANARY ISLANDS NEAR 29N12W WITH RIDGE AXIS EXTENDING SW TO 15N40W. EXPECT...TROPICAL CONVECTION ALONG THE ITCZ...AND WITH THE TROPICAL WAVES OVER THE NEXT 24 HOURS. $$ FORMOSA