000 AXNT20 KNHC 270556 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 40W S OF 16N MOVING W NEAR 23 KT. THIS WAVE COINCIDES WITH A BROAD MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. REMAINING EMBEDDED WITHIN THE ITCZ...A BROAD LOW-LEVEL CYCLONIC TURNING IS EVIDENT IN THE LOW LEVEL FLOW WITHIN THE 950-800 MB LAYER ALONG THE WAVE AXIS NEAR 10N. SCATTERED MODERATE CONVECTION IS FROM 8N-13N BETWEEN 37W-42W. A TROPICAL WAVE IS ALONG 62W S OF 18N MOVING W NEAR 25-30 KT. THIS WAVE COINCIDES WITH A WELL-DEFINED MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. INFRARED SATELLITE IMAGERY INDICATES AN INVERTED-V SIGNATURE IN THE COVERAGE OF LOW LEVEL CLOUDS NEAR THIS WAVE. SCATTERED SHOWERS ARE OCCURRING FROM 10N-16N BETWEEN 60W-66W. A TROPICAL WAVE IS ALONG 93W S OF 20N MOVING W NEAR 18 KT. THIS WAVE IS EMBEDDED WITHIN A BROAD MAXIMUM IN DEEP LAYER MOISTURE BASED ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 14N-19N BETWEEN 92W-100W. THIS CONVECTION IS BEING ENHANCED BY UPPER LEVEL DIVERGENCE ASSOCIATED WITH AN UPPER LEVEL RIDGE EXTENDING FROM THE NW CARIBBEAN WWD OVER SRN MEXICO AND THE ADJACENT COASTAL WATERS. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 13N17W 10N38W 10N41W 10N60W. SCATTERED MODERATE CONVECTION IS FROM 9N-13N BETWEEN 18W-23W. ...DISCUSSION... GULF OF MEXICO... A SHARP UPPER LEVEL TROUGH IS OVER THE N/CENTRAL AND NE GULF WITH AN AXIS EXTENDING FROM THE SE CONUS THROUGH 27N90W TO 22N96W. ATMOSPHERIC LIFT IN MOIST SWLY FLOW ALOFT TO THE E OF THE UPPER LEVEL TROUGH AXIS IS SUPPORTING SCATTERED SHOWERS AND ISOLATED TSTMS OVER THE CENTRAL AND SW GULF WITHIN 150 NM EITHER SIDE OF A LINE FROM 28N85W TO 20N94W. THIS SHOWER AND TSTM ACTIVITY IS ALSO BEING SUPPORTED BY LOW LEVEL SPEED CONVERGENCE IN THE SURFACE WIND FIELD ACROSS THE CENTRAL GULF. ACROSS THE NW GULF...SUBSIDENCE IN NLY FLOW ALOFT W OF THE UPPER LEVEL TROUGH AXIS...AS WELL AS DEEP LAYER DRY AIR...ARE RESULTING IN OVERALL FAIR WEATHER WITH ONLY REMNANT CONVECTIVE DEBRIS HIGH CLOUDS ACROSS THE NRN GULF. SELY SURFACE WINDS ARE FORECAST TO INCREASE OVER THE W GULF LATE MONDAY...AS A SURFACE RIDGE ACROSS THE NRN GULF MOVES NEWD DURING THE NEXT FEW DAYS AND SURFACE LOW PRESSURE DEVELOPS OVER W TEXAS/NRN MEXICO. CARIBBEAN SEA... AN UPPER LEVEL RIDGE IS PRESENT OVER THE NW CARIBBEAN...YUCATAN PENINSULA AND WRN CUBA THAT EXTENDS FROM AN UPPER LEVEL HIGH CENTERED NEAR 20N86W. UPPER LEVEL DIVERGENCE ASSOCIATED WITH THIS UPPER LEVEL RIDGE IS SUPPORTING SCATTERED SHOWERS N OF 21N W OF 82W. THE REMAINDER OF THE CARIBBEAN REMAINS FAIRLY TRANQUIL UNDER DEEP LAYER DRY AIR AS MODERATE TO STRONG SUBSIDENCE PREVAILS BETWEEN 67W-85W. HOWEVER...WEAK LOW-LEVEL CONVERGENCE AND A REGIONAL AREA OF UPPER DIFFLUENCE IS LOCATED OVER WRN HISPANIOLA AND IS SUPPORTING SCATTERED SHOWERS AND ISOLATED TSTMS FROM 18N-20N BETWEEN 72W-75W. FRESH TO STRONG TRADE WINDS ARE OCCURRING ACROSS THE BASIN S OF A SURFACE RIDGE OVER THE CENTRAL AND W ATLC. THE STRONGEST WINDS ARE FOUND NEAR THE COAST OF COLOMBIA...WHERE NE WINDS OF 25 TO 30 KT ARE OCCURRING. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH IS PRESENT OVER THE ERN CONUS AND EXTENDS INTO THE NE GULF OF MEXICO. ATMOSPHERIC LIFT IN MOIST SWLY FLOW ALOFT BETWEEN THIS UPPER LEVEL TROUGH AND AN UPPER LEVEL RIDGE FARTHER TO THE E OVER THE SW NORTH ATLC CENTERED NEAR 29N71W IS SUPPORTING SCATTERED SHOWERS AND TSTMS N OF 25N W OF 78W. TO THE E...AN UPPER LEVEL LOW IS CENTERED NEAR 30N60W. ATMOSPHERIC INSTABILITY IN THE VICINITY OF THIS UPPER LEVEL LOW IS PRODUCING ISOLATED SHOWERS N OF 27N BETWEEN 54W-61W. ACROSS THE REMAINDER OF THE CENTRAL AND ERN ATLC...SUBSIDENCE AND ATMOSPHERIC STABILITY PREVAIL ASSOCIATED WITH A SURFACE RIDGE ANCHORED ON A 1030 MB HIGH CENTERED NEAR 34N47W THAT IS RESULTING IN GENERALLY FAIR WEATHER. HOWEVER...A SURFACE TROUGH EXTENDS FROM WRN MAURITANIA TO 18N22W IN THE ERN ATLC WITH NE WINDS UP TO 25 KT FOUND ON AN EARLIER SCATTEROMETER PASS FROM 24N-30N E OF 26W. $$ HUFFMAN