000 AXNT20 KNHC 091800 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT FRI JUL 09 2010 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1600 UTC... ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 17N29W TO 5N32W MOVING W NEAR 15 KT. THE WAVE LIES AHEAD OF A DEEP LAYER MOISTURE MAXIMUM EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. BROAD CYCLONIC FLOW IS ALSO AROUND THE WAVE AXIS SEEN IN VISIBLE SATELLITE IMAGERY DUE TO A DRY SAHARAN AIR LAYER ACCOMPANIED BY DUST THAT EXTENDS AROUND THE WAVE...CONVECTION IS RESTRICTED TO THE ITCZ WHERE SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 3N-8N BETWEEN 30W-34W. TROPICAL WAVE EXTENDS FROM 17N56W TO 8N60W MOVING W 15-20 KT AND APPROACHING THE WINDWARD ISLANDS. BROAD CYCLONIC FLOW IS ABOUT THE WAVE AXIS EVIDENT IN VISIBLE SATELLITE IMAGERY. THE WAVE ALSO LIES AHEAD OF A DEEP LAYER MOISTURE MAXIMUM INDICATED BY TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 8N-14N BETWEEN 54W-60W. SIMILAR ACTIVITY IS ALSO FROM 9N-13N BETWEEN 61W-64W. TROPICAL WAVE EXTENDS FROM 15N65W TO 9N67W MOVING W NEAR 15 KT. THE WAVE LIES AHEAD OF A LOW AMPLITUDE MAXIMUM IN DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. CYCLONIC FLOW IS IN THE VICINITY OF THE WAVE AXIS INDICATED BY VISIBLE SATELLITE IMAGERY. SCATTERED MODERATE/ISOLATED CONVECTION IS FROM 10N-14N BETWEEN 65W-69W. TROPICAL WAVE EXTENDS FROM S OF WRN CUBA NEAR 22N84W TO PANAMA NEAR 9N81W MOVING W NEAR 10 KT. WAVE IS AHEAD OF A DEEP LAYER MOISTURE MAXIMUM EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/STRONG CONVECTION IS NEAR THE SRN EXTENT OF THE WAVE FROM 9N-14N BETWEEN 81W-85W. A LARGE CLUSTER OF STRONG CONVECTION IS E OF THE WAVE FROM 10N-14N BETWEEN 76W-80W. HOWEVER...THIS MAY BE ASSOCIATED MORE WITH DIFFLUENCE ALOFT AND CONVERGENCE NEAR THE ITCZ. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO NEAR THE NRN EXTENT OF THE WAVE ACROSS WRN CUBA FROM 18N-23N BETWEEN 80W-86W. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 12N16W 9N33W 7N45W 11N58W. SCATTERED MODERATE CONVECTION IS FROM 10N-15N BETWEEN 19W027W. SIMILAR ACTIVITY IS FROM 4N-9N BETWEEN 38W-42W. ...DISCUSSION... GULF OF MEXICO... TROPICAL DEPRESSION TWO REMAINS INLAND OVER NRN MEXICO NEAR 26.6N 102.1W SUPPORTING SCATTERED SHOWERS/POSSIBLE THUNDERSTORMS ACROSS MUCH OF SRN TEXAS AND NE MEXICO. TOTAL PRECIPITABLE WATER IMAGERY STILL INDICATES STRONG MOISTURE ALONG THE FAR WRN GULF OF MEXICO WHERE A SURFACE TROUGH IS ANALYZED HUGGING THE MEXICO COASTLINE FROM 23N97W TO 18N93W. SURFACE RIDGING IS BUILDING ACROSS THE ERN AND CENTRAL GULF PROVIDING GENERALLY FAIR WEATHER ACROSS THE REMAINDER OFT HE BASIN. A FEW ISOLATED SHOWERS/THUNDERSTORMS ARE IN THE FAR SERN GULF DUE TO A SURFACE TROUGH ANALYZED W OF S FLORIDA FROM 26N82W TO 24N83W...AND A TROPICAL WAVE S OF WRN CUBA. ALOFT...DRY AIR IS ACROSS MUCH OF THE BASIN AROUND AN UPPER LEVEL LOW CENTERED OVER THE YUCATAN PENINSULA NEAR 20N90W. EXPECT SURFACE RIDING TO CONTINUE TO BUILD ACROSS THE BASIN KEEPING CONDITIONS FAIR. CARIBBEAN SEA... SCATTERED SHOWERS/THUNDERSTORMS ARE ACROSS THE NW AND SW CARIBBEAN DUE TO A TROPICAL WAVE EXTENDING FROM FAR W CUBA TO PANAMA. SEE TROPICAL WAVE SECTION FOR MORE DETAILS. A LARGE CLUSTER OF STRONG CONVECTION IS N OF PANAMA FROM 10N-14N BETWEEN 76W-80W. THIS MAY BE INFLUENCED BY SURFACE CONVERGENCE NEAR AN EXTENSION OF THE ITCZ FROM COSTA RICA TO COLOMBIA...THE TROPICAL WAVE TO THE W...AND ALSO DIFFLUENCE ALOFT BETWEEN AN UPPER LEVEL RIDGE COVERING THE ERN CARIBBEAN CENTERED NEAR 13N69W AND ELY FLOW ALOFT ACROSS THE SW CARIBBEAN AND INTO THE E PACIFIC. AN UPPER LEVEL TROUGH COVERS THE NW CARIBBEAN AROUND AN UPPER LEVEL LOW CENTERED OVER THE YUCATAN PENINSULA. A TROPICAL WAVE ACROSS THE ERN CARIBBEAN AND VENEZUELA IS ENHANCING SCATTERED SHOWERS/THUNDERSTORMS FROM 10N-14N BETWEEN 65W-69W. THE REMAINDER OF THE BASIN IS UNDER MAINLY CLEAR SKIES AND FAIR WEATHER UNDER THE INFLUENCE OF DRY AIR AROUND THE AFOREMENTIONED UPPER LEVEL RIDGE COVERING THE ERN CARIBBEAN. EXPECT SHOWER ACTIVITY TO REMAIN NEAR BOTH TROPICAL WAVES AS THEY PROGRESS WWD...AND NEAR A THIRD TROPICAL WAVE CURRENTLY E OF THE WINDWARD ISLANDS THAT IS ALREADY PRODUCING CONVECTION APPROACHING THE AREA. ATLANTIC OCEAN... AN UPPER LEVEL LOW SPINNING N OF THE DISCUSSION AREA NEAR 35N75W CONTINUES TO AFFECT THE WRN ATLC SUPPORTING SEVERAL SURFACE TROUGHS. ONE TROUGH EXTENDS FROM N OF THE AREA FROM A LOW NEAR THE NORTH CAROLINA COAST ENTERING THE DISCUSSION AREA NEAR 32N74W TO 30N79W. SCATTERED SHOWERS/THUNDERSTORMS ARE WITHIN 60 NM EITHER SIDE OF THE AXIS. A SECOND TROUGH EXTENDS FROM 30N69W TO 27N77W. ISOLATED SHOWERS/THUNDERSTORMS ARE ACROSS THE WRN BAHAMAS. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO FROM 24N-30N BETWEEN 66W-74W. SOME OF THIS ACTIVITY IS ENHANCED BY DIFFLUENCE ALOFT BETWEEN THE UPPER LOW CIRCULATION AND AN UPPER LEVEL RIDGE CENTERED OVER THE ERN CARIBBEAN NEAR 13N69W. FARTHER E...A BROAD SURFACE RIDGE DOMINATES ANCHORED BY A 1029 MB HIGH NEAR 37N54W. HOWEVER...A WEAK SURFACE TROUGH EXTENDS FROM 28N56W TO 22N57W COLLOCATED WITH AN UPPER LEVEL LOW NEAR 24N55W. ISOLATED SHOWERS ARE WITHIN 90 NM EITHER SIDE OF THE SURFACE TROUGH AXIS. ALOFT...AN UPPER LEVEL RIDGE IS E OF THE UPPER LEVEL LOW CENTERED NEAR 23N38W. A NARROW UPPER LEVEL TROUGH IS BETWEEN THIS UPPER RIDGE AND A SECOND UPPER RIDGE CENTERED OVER NW AFRICA NEAR 26N2W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON