000 AXNT20 KNHC 221748 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT MAY 22 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 1645 UTC... ...SPECIAL FEATURES... A BROAD CIRCULATING 1011 MB LOW IS LOCATED N OF HISPANIOLA NEAR 22N70W. A SURFACE TROUGH EXTENDS THROUGH THE LOW CENTER FROM NEAR 28N67W ALONG 24N68W 22N70W AND ACROSS HISPANIOLA NEAR 19N71W 18N73W. ISOLATED SHOWERS/THUNDERSTORMS ARE ACROSS MUCH OF ERN CUBA...HISPANIOLA...JAMAICA...AND PUERTO RICO N OF 17N BETWEEN 66W-78W. STRONGER CONVECTION IS E OF THE TROUGH AXIS FROM 21N-29N BETWEEN 60W-67W. THIS SYSTEM GETS ITS UPPER LEVEL SUPPORT FROM AN UPPER LEVEL LOW FORMING NEAR 27N68W PROVIDING A DIFFLUENT ZONE ALOFT TO THE E WHERE THE MAIN AREA OF CONVECTION IS. THE SURFACE LOW IS FORECAST TO DEEPEN OVER THE NEXT 24 HRS AS IT MOVES MAINLY N. GALE FORCE WINDS ARE EXPECTED TO DEVELOP NE OF THE LOW CENTER WITHIN 18 HRS. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 7N36W TO 1N37W MOVING W AT 10-15 KT. THIS LOCATION IS E OF THE PREVIOUS ANALYSIS BASED ON SCATTEROMETER DATA AND VISIBLE SATELLITE IMAGERY INDICATING LOW-LEVEL CYCLONIC FLOW NEAR THE CURRENT LOCATION OF THE WAVE AXIS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 5N-7N BETWEEN 33W-40W. TROPICAL WAVE IS ADDED FROM 9N52W TO 2N51W MOVING W 10-25 KT. LOCATION IS BASED ON LONG-TERM ANALYSIS OF LOW TO MID-LEVEL COMPUTER MODEL DATA INDICATING A TRACKABLE AREA OF ENHANCED MOISTURE AND ENERGY ALONG WITH CYCLONIC FLOW FROM ACROSS THE ATLC TO CURRENT LOCATION. BROAD LOW-LEVEL CYCLONIC FLOW CAN ALSO BE SEEN IN VISIBLE SATELLITE IMAGERY. THE WAVE ALSO COINCIDES WITH A MAXIMUM IN DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/STRONG CONVECTION IS FROM 7N-12N BETWEEN 49W-55W. SIMILAR ACTIVITY IS FROM 2N-5N BETWEEN 50W-52W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 8N-12N BETWEEN 47W-49W. TROPICAL WAVE IS ALONG 61/62W S OF 9N MOVING W AT 10-15 KT. THIS WAVE LIES W OF A DEEP LAYER MOISTURE MAXIMUM IN TOTAL PRECIPITABLE WATER IMAGERY. NO DEEP CONVECTION IS CURRENTLY ASSOCIATED WITH THE WAVE. TROPICAL WAVE EXTENDS FROM 11N80W ACROSS PANAMA AND INTO THE E PACIFIC ALONG 7N80W 4N83W. BROAD LOW-LEVEL CYCLONIC FLOW IS ABOUT THE WAVE AXIS. THE WAVE LIES EMBEDDED IN A LARGE AREA OF DEEP LAYER MOISTURE THAT COVERS THE W ATLC AND FAR E PACIFIC. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 9N-12N BETWEEN 78W-82W. MORE CONVECTION IS LOCATED IN THE E PACIFIC. SEE THE E PACIFIC TWD FOR MORE DETAILS. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N12W 5N20W 4N30W 5N40W 2N50W. ISOLATED MODERATE/STRONG CONVECTION IS OFF THE COAST OF AFRICA FROM 5N-10N BETWEEN 10W-20W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 3N-6N BETWEEN 25W-29W. SIMILAR ACTIVITY IS FROM 5N-7N BETWEEN 43W-47W. ...DISCUSSION... GULF OF MEXICO... WEAK SURFACE RIDGING EXTENDS ACROSS THE GULF OF MEXICO FROM THE NE KEEPING CONDITIONS FAIR ACROSS THE BASIN. THE SURFACE RIDGE IS SUPPORTED BY AN UPPER LEVEL RIDGE EXTENDING FROM S OF MEXICO ACROSS THE WRN HALF OF THE GULF AND NWD ACROSS THE MISSISSIPPI VALLEY. THE UPPER RIDGE IS ACCOMPANIED BY DRY AIR AND SUBSIDENCE ALOFT FURTHER GENERATING THE FAIR WEATHER. A WEAK SURFACE TROUGH IS NOTED ACROSS THE YUCATAN PENINSULA FROM 22N92W TO 18N88W. POSSIBLE ISOLATED SHOWERS ARE NW OF THE TROUGH FROM 20N-23N BETWEEN 92W-94W. EXPECT LITTLE CHANGE OVER THE NEXT 24 HRS. CARIBBEAN SEA... A SURFACE TROUGH IS IMPACTING THE NW CARIBBEAN FROM 19N85W TO ERN HONDURAS NEAR 15N84W. SURFACE CONVERGENCE NEAR THE TROUGH ALONG WITH SIGNIFICANT DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY ARE SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS MAINLY E OF THE TROUGH AXIS FROM 13N-19N BETWEEN 81W-85W. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO FROM 17N-20N BETWEEN 71W-80W ASSOCIATED WITH ENHANCED MOISTURE ACROSS THIS AREA. SOME OF THESE SHOWERS ACROSS HISPANIOLA ARE ALSO ATTRIBUTED TO A DEEP LAYER TROUGH ACROSS THE W ATLC. SEE SPECIAL FEATURES ABOVE. SCATTERED SHOWERS/THUNDERSTORMS ARE ACROSS THE SW CARIBBEAN FROM 9N-12N BETWEEN 78W-82W DUE TO SURFACE CONVERGENCE NEAR A TROPICAL WAVE ALONG 80W. THE REMAINDER OF THE BASIN IS EXPERIENCING GENERALLY FAIR WEATHER AROUND AN UPPER LEVEL RIDGE CENTERED OVER VENEZUELA. ATLANTIC OCEAN... DRY AIR ALOFT FLOWING FROM OVER THE GULF OF MEXICO IS KEEPING CONDITIONS FAIR W OF 75W. HOWEVER...A BROAD DEEP LAYER TROUGH IS AFFECTING MUCH OF THE REMAINING W ATLC. A 1011 MB LOW IS CENTERED N OF HISPANIOLA NEAR 22N70W WITH AN ASSOCIATED SURFACE TROUGH ALONG 28N67W 24N68W 22N70W AND ACROSS HISPANIOLA NEAR 19N71W 18N73W. THE SYSTEM IS BRINGING SHOWERS/THUNDERSTORMS TO MUCH OF THE W ATLC. SEE SPECIAL FEATURES ABOVE FOR MORE DETAILS ON THIS LOW PRESSURE SYSTEM. A SECOND SURFACE TROUGH...REMNANTS OF A PREVIOUS LOW PRESSURE CIRCULATION...EXTENDS FROM 25N74W ACROSS THE SE BAHAMAS TO NEAR 22N72W. POSSIBLE ISOLATED SHOWERS ARE WITHIN 60 NM EITHER SIDE OF THE AXIS. ISOLATED SHOWERS/THUNDERSTORMS ARE ALSO E AND N OF THE LESSER ANTILLES FROM 14N-23N BETWEEN 53W-60W. TOTAL PRECIPITABLE WATER IMAGERY INDICATES ENHANCED DEEP LAYER MOISTURE ACROSS THIS AREA. THE REMAINDER OF THE CENTRAL AND E ATLC IS DOMINATED BY SURFACE RIDGING ANCHORED BY A STATIONARY 1030 MB HIGH SW OF THE AZORES ISLANDS NEAR 36N36W. THE RIDGE IS SUPPORTED BY AN UPPER LEVEL RIDGE N OF 30N ALONG 36W. S OF 30N A BROAD UPPER LEVEL TROUGH IS ALONG 38W ALLOWING MAINLY SWLY ALOFT FROM NE SOUTH AMERICA TO THE W AFRICA COAST. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON