000 AXNT20 KNHC 181101 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE MAY 17 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1000 UTC... ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 21N S OF 7N MOVING W AT 10-15 KT. WAVE POSITION IS BASED ON ANALYSIS OF LONG TERM SATELLITE IMAGERY AND HOVMOLLER DIAGRAMS. THE WAVE ALSO COINCIDES WITH A SMALL PEAK IN DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS EMBEDDED WITHIN THE ITCZ AND IS FROM 3N-7N BETWEEN 18W-24W. TROPICAL WAVE IS ALONG 37W S OF 7N MOVING W AT 15-20 KT. THE WAVE IS EMBEDDED IN A LARGE AREA OF DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. CONVECTION REMAINS EMBEDDED IN THE ITCZ. SCATTERED STRONG CONVECTION IS FROM 4N-8N BETWEEN 35W-39W. TROPICAL WAVE EXTENDS FROM 13N63W TO 1N65W MOVING W NEAR 15 KT. THE WAVE COINCIDES WITH A MAXIMUM OF DEEP LAYER MOISTURE AS INDICATED IN TOTAL PRECIPITABLE WATER IMAGERY OVER THE SE CARIBBEAN SEA. SURFACE OBSERVATIONS ALSO INDICATED CYCLONIC FLOW ABOUT THE WAVE AXIS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS E OF THE WAVE AXIS FROM 4N-8N BETWEEN 60W-64W. SCATTERED STRONG CONVECTION IS W OF THE AXIS FROM 7N-10N BETWEEN 65W-69W. TROPICAL WAVE IS ALONG 73W S OF 11N MOVING W NEAR 15 KT. A CLUSTER OF STRONG CONVECTION IS NEAR 10N72W. NO OTHER DEEP CONVECTION IS CURRENTLY ASSOCIATED WITH THIS WAVE. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 9N8W 4N20W 3N30W 5N40W AND INTO NE BRAZIL NEAR 2N55W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 3N-9N BETWEEN 10W-15W. SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 120 NM EITHER SIDE OF THE AXIS BETWEEN 25W-35W. SIMILAR ACTIVITY IS FROM 4N-7N BETWEEN 40W-48W AROUND AN EMBEDDED SURFACE TROUGH ALONG 7N43W TO 1N45W. ...DISCUSSION... GULF OF MEXICO... THE SHORTWAVE UPPER LEVEL TROUGH THAT WAS PREVIOUSLY ACROSS THE ERN GULF OF MEXICO HAS NOW SHIFTED E OVER THE W ATLC. HOWEVER... A SURFACE TROUGH STILL EXTENDS ACROSS THE FLORIDA PENINSULA FROM W OF JACKSONVILLE TO NEAR FORT MYERS. SHOWER ACTIVITY ASSOCIATED WITH THIS SYSTEM HAS MOVED E OF THE BASIN INTO THE W ATLC. A SECOND SURFACE TROUGH REMAINS IN THE SW GULF 20N91W TO 17N92W. ISOLATED SHOWERS ARE POSSIBLE ACROSS THE YUCATAN PENINSULA. THE REMAINDER OF THE BASIN IS COVERED BY SURFACE RIDGING NEAR A 1017 MB HIGH S OF MOBILE ALABAMA NEAR 27N87W WITH MAINLY ZONAL FLOW ALOFT COVERING THE BASIN DRAWING MODERATE MOISTURE ACROSS THE WRN AND CENTRAL GULF SUPPORTING HIGH CLOUDS. STRONG SHOWERS/THUNDERSTORMS ALONG AN OUTFLOW BOUNDARY HAVE MOVED INTO THE NW GULF WATERS AHEAD OF A FRONTAL BOUNDARY ACROSS TEXAS. SCATTERED SHOWERS/THUNDERSTORMS ARE N OF 26N W OF 94W. THIS FRONTAL BOUNDARY WILL IMPACT THE COASTAL GULF WATERS BEFORE WEAKENING THROUGH THURSDAY ALLOWING SURFACE RIDGING TO RE-ESTABLISH ACROSS THE WRN GULF. CARIBBEAN SEA... DIFFLUENT FLOW ALOFT BETWEEN A WEAK SHORTWAVE UPPER LEVEL TROUGH ACROSS THE W ATLC AND AN UPPER LEVEL RIDGE CENTERED N OF PANAMA IS SUPPORTING ISOLATED SHOWERS/POSSIBLE THUNDERSTORMS ACROSS THE NW GULF AND CUBA N OF 15N W OF 78W. SCATTERED SHOWERS/THUNDERSTORMS HAVE ALSO FORMED ALONG THE COSTA RICA/PANAMA COASTLINE. FARTHER E...A SURFACE TROUGH EXTENDS ACROSS ERN HISPANIOLA ALONG 21N66W TO 17N71W. ENHANCED LOW-LEVEL MOISTURE IS EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY TO THE E OF THIS TROUGH ACROSS THE LESSER ANTILLES. AS A RESULT OF THE ENHANCED MOISTURE ALONG WITH SURFACE CONVERGENCE NEAR THE TROUGH...ISOLATED SHOWERS ARE ACROSS THE NW CARIBBEAN N OF 16N E OF 71W. ISOLATED SHOWERS ARE ALSO ACROSS THE SRN WINDWARD ISLANDS DUE TO SURFACE CONVERGENCE AND ENHANCED MOISTURE NEAR A TROPICAL WAVE ALONG 64W/65W. ATLANTIC OCEAN... AN UPPER LEVEL SHORTWAVE TROUGH PREVIOUSLY OVER THE ERN GULF HAS PUSHED OVER THE W ATLC PROVIDING A LARGE AREA OF DIFFLUENT FLOW ALOFT ACROSS THE WRN ATLC SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS FROM N OF 25N BETWEEN 76W-79W. THE REMAINDER OF THE BASIN IS DOMINATED BY SURFACE RIDGING AROUND A 1021 MB HIGH NEAR 29N58W...AND A 1029 MB AZORES HIGH NEAR 39N19W PROVIDING GENERALLY FAIR WEATHER ACROSS MUCH OF THE BASIN. HOWEVER...A SERIES OF WEAK SURFACE TROUGHS ARE IMPACTING AREAS N OF THE CARIBBEAN. THE FIRST TROUGH EXTENDS FROM 26N68W TO 24N68W ENHANCING ISOLATED SHOWERS WITHIN 60 NM EITHER SIDE OF THE AXIS. THE SECOND EXTENDS ACROSS ERN HISPANIOLA FROM 21N66W TO 17N71W ENHANCING ISOLATED SHOWERS ACROSS MUCH OF THE NE CARIBBEAN ISLANDS. THE FINAL TROUGH EXTENDS FROM 24N57W TO 16N58W ENHANCING ISOLATED SHOWERS WITHIN 75 NM EITHER SIDE OF THE AXIS. ALOFT...A WEAK UPPER LEVEL RIDGE IS ALONG 70W WITH MAINLY ZONAL WLY FLOW COVERING THE REMAINDER OF THE W AND CENTRAL ATLC. AN UPPER LEVEL TROUGH COVERS THE FAR E ATLC FROM NEAR SRN SPAIN TO THE CAPE VERDE ISLANDS. A BROAD AND FLAT UPPER LEVEL RIDGE COVERS THE TROPICAL ATLC S OF 17N. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON