000 AXNT20 KNHC 220530 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU APR 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0445 UTC... ...THE ITCZ... ITCZ AXIS IS CENTERED FROM GUINEA NEAR 10N13W ALONG 4N20W CROSSING THE EQ NEAR 27W TO INLAND BRAZIL NEAR 3S40W 3N50W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 6N-8N BETWEEN 10W-13W. SCATTERED STRONG CONVECTION IS FROM 5N-6N BETWEEN 15W-19W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 1N-3N BETWEEN 32W-42W. ...DISCUSSION... THE GULF OF MEXICO... A SURFACE RIDGE CONTINUES TO IMPACT THE GULF OF MEXICO TONIGHT ANCHORED BY A 1013 MB HIGH NEAR 29N88W KEEPING CONDITIONS FAIR ACROSS THE BASIN. AN UPPER LEVEL RIDGE EXTENDS ACROSS THE GREAT PLAINS AND THE WRN GULF SUPPORTING THE SURFACE RIDGE. AN UPPER LEVEL TROUGH EXTENDS TO THE E WITH AXIS JUST E OF THE FLORIDA PENINSULA. WATER VAPOR IMAGERY INDICATES DRY AIR AND SUBSIDENCE ACROSS THE ERN HALF OF THE BASIN BETWEEN THE UPPER RIDGE AND UPPER TROUGH...WHILE UPPER LEVEL MOISTURE FLOWS FROM THE E PACIFIC ACROSS CENTRAL MEXICO TO THE WRN GULF SUPPORTING HIGH CLOUDS. EXPECT THE SURFACE RIDGE TO SHIFT EWD ALLOWING SLY RETURN FLOW TO INCREASE ACROSS THE WRN GULF AHEAD OF A COLD FRONT FORECAST TO MOVE OFF THE TEXAS COAST LATE FRI. THE CARIBBEAN SEA... SCATTERED SHOWERS/THUNDERSTORMS HAVE FORMED ACROSS HONDURAS OVER THE PAST SEVERAL HOURS. AS OF 0300 UTC...A SURFACE TROUGH IS ANALYZED IN THE FAR NW CARIBBEAN FROM 20N86W ACROSS HONDURAS TO 13N88W. SURFACE CONVERGENCE NEAR THE TROUGH IS MOST LIKELY ENHANCING THE SHOWER ACTIVITY ACROSS HONDURAS ALONG WITH SLIGHT DIFFLUENCE ALOFT AROUND THE BROAD BASE OF AN UPPER LEVEL TROUGH IN THE FAR W ATLC THAT EXTENDS OVER THE NW CARIBBEAN. THE REMAINDER OF THE CARIBBEAN IS EXPERIENCING GENERALLY FAIR WEATHER UNDER THE INFLUENCE OF AN UPPER LEVEL RIDGE CENTERED E OF THE LESSER ANTILLES. MODERATE TRADE WINDS ARE ACROSS THE MAJORITY OF THE AREA. EXPECT LITTLE CHANCE OVER THE NEXT 24 HRS. THE ATLANTIC OCEAN... AN UPPER LEVEL TROUGH OVER THE FAR W ATLC EXTENDS E OF THE FLORIDA PENINSULA SUPPORTING A LOW PRESSURE SYSTEM OFF THE COAST OF N CAROLINA. A SURFACE TROUGH HUGS THE ENTIRE FLORIDA PENINSULA COASTLINE. A FEW ISOLATED SHOWERS ARE NOTED E OF THE TROUGH AXIS. AN UPPER LEVEL RIDGE EXTENDS FROM E OF THE LESSER ANTILLES ALONG 50W SUPPORTING A WEAK SURFACE RIDGE ANCHORED BY A 1016 MB HIGH NEAR 29N56W. HOWEVER...A FRONTAL SYSTEM DISRUPTS THE RIDGE WITH A COLD FRONT ENTERING THE DISCUSSION AREA ALONG 32N40W 25N52W TO A 1010 MB LOW NEAR 24N65W CONTINUING TO NE HISPANIOLA NEAR 19N69W. SCATTERED SHOWERS ARE WITHIN 200 NM E OF THE FRONT AXIS N OF 27N...AND FROM 21N-30N BETWEEN 50W-65W. ISOLATED SHOWERS ARE ALSO WITHIN 90 NM EITHER SIDE OF THE FRONT AXIS S OF THE LOW PRESSURE CENTER. THIS SYSTEM IS SUPPORTED BY AN UPPER LEVEL LOW E OF NEWFOUNDLAND WITH UPPER TROUGH AXIS EXTENDING SE TO NEAR 33N28W. ACROSS THE E ATLC...A SURFACE RIDGE DOMINATES ANCHORED BY A 1020 MB HIGH NEAR 26N29W PROVIDING GENERALLY FAIR WEATHER ACROSS THAT PORTION OF THE BASIN. THE SURFACE RIDGE IS SUPPORTED BY A NARROW UPPER LEVEL RIDGE ALONG 20W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON