000 AXNT20 KNHC 211838 CCA TWDAT TROPICAL WEATHER DISCUSSION...UPDATED NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 235 PM EDT THU OCT 21 2010 *** AREA OF CONVECTION CORRECTED ON TROPICAL WAVE SECTION *** 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 1745 UTC. ...SPECIAL FEATURE... TROPICAL DEPRESSION NINETEEN BECAME TROPICAL STORM RICHARD AT 21/1500 UTC LOCATED NEAR 16.2N 80.4W. THIS LOCATION IS ABOUT 220 MI...355 KM SSE OF GRAND CAYMAN AND 205 MI...330 KM ENE OF CABO GRACIAS A DIOS ON THE NICARAGUA AND HONDURAS BORDER. RICHARD IS MOVING SE AT 5 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 35 KT WITH GUSTS TO 45 KT. PLEASE READ THE FORECAST/ADVISORY LISTED UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC...AND THE INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT4/WTNT34 KNHC FOR MORE DETAILS. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 13N-20N BETWEEN 77W-81W. ...TROPICAL WAVE... A VIGOROUS TROPICAL WAVE IS OVER THE FAR EAST TROPICAL ATLANTIC EMBEDDED IN THE ITCZ. WAVE AXIS IS ANALYZED FROM 16N20W TO 5N22W MOVING W AT ABOUT 15 KT. THIS SYSTEM IS EMBEDDED IN A SURGE OF DEEP LAYER MOISTURE NOTED ON TOTAL PRECIPITABLE WATER IMAGERY. BROAD CYCLONIC CURVATURE IS OBSERVED ALONG THE AXIS. SCATTERED MODERATE TO ISOLATE STRONG CONVECTION IS FROM 5N-15N BETWEEN 18W-28W. EVEN THOUGH THIS IS HISTORICALLY NOT A FAVORABLE AREA FOR TROPICAL CYCLONE FORMATION IN LATE OCTOBER...THIS SYSTEM IS SHOWING SOME SIGNS OF ORGANIZATION...AND ENVIRONMENTAL CONDITIONS ARE MARGINALLY CONDUCIVE FOR SOME ADDITIONAL DEVELOPMENT TO OCCUR. LOCALLY HEAVY RAINFALL IS POSSIBLE OVER THE SOUTHERN CAPE VERDE ISLANDS TODAY AND TONIGHT. ...THE ITCZ... ITCZ AXIS IS ANALYZED WEST OF THE TROPICAL WAVE ALONG 8N23W 7N30W 10N38W...RESUMING NEAR 9N45W 6N51W TO THE COAST OF GUYANA NEAR 7N58W. A SURFACE TROUGH IS N OF THE ITCZ EXTENDING FROM 18N40W THROUGH A 1012 MB LOW NEAR 13N42W TO 10N43W PRODUCING CLUSTERS OF SCATTERED MODERATE CONVECTION FROM 14N-17N BETWEEN 35W-41W. ANOTHER BUT RATHER WEAK SURFACE TROUGH IS EMBEDDED IN THE ITCZ EXTENDING FROM 10N30W TO 5N31W. CLUSTERS OF SCATTERED WEAK CONVECTION ARE WITHIN 60 NM ON EITHER SIDE OF THE ITCZ AXIS BETWEEN 27W AND 38W. ...DISCUSSION... THE GULF OF MEXICO... A BROAD MID-UPPER RIDGE CENTERED OVER THE FAR WESTERN GULF CONTINUES TO DOMINATE THE AREA OF DISCUSSION...GIVING MOSTLY CLEAR SKIES WITH FEW AREAS OF SCATTER LOW LEVEL STRATOCUMULUS CLOUDS EMBEDDED IN THE LIGHT ANTICYCLONIC SFC FLOW. THIS FLOW IS CENTERED AROUND A 1019 MB HIGH NEAR 27N93W. STRONG SUBSIDENCE AND DRY AIR ALOFT WILL CONTINUE OVER THE NEXT 24 HOURS. THE CARIBBEAN SEA... TROPICAL STORM RICHARD IS OVER THE WESTERN CARIBBEAN PRODUCING MODERATE TO STRONG CONVECTION FROM 13N-20N BETWEEN 77W-81W. SEE SPECIAL FEATURES ABOVE FOR MORE DETAILS. ELSEWHERE OUTSIDE THE CONVECTION ASSOCIATED WITH RICHARD...DRY AND STABLE AIR ALOFT COVERS MOST OF THE AREA OF DISCUSSION PROVIDING RELATIVELY FAIR WEATHER CONDITIONS WITH A FEW AREAS OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS EMBEDDED IN THE TRADE WINDS. SE FLOW ALOFT IS OBSERVED OVER THE EASTERN CARIBBEAN DRAWING SOME LIMITED MID-UPPER LEVEL MOISTURE FROM NORTHERN S AMERICA. THIS SCENARIO WILL CONTINUE OVER THE NEXT FEW DAYS ENHANCING AREAS OF SCATTERED WEAK TO MODERATE CONVECTION ACROSS THE CENTRAL AND EASTERN CARIBBEAN. THE ATLANTIC OCEAN... A BROAD MID-UPPER LEVEL TROUGH MOVES OFF THE NORTH AMERICA SEABOARD...WHILE A BROAD UPPER LEVEL RIDGE IS IN THE CENTRAL ATLC. THIS WEATHER SCENARIO IS DRAWING DEEP MOISTURE FROM THE SW CARIBBEAN TO THE WESTERN ATLC...GENERATING AN AREA OF DEEP LAYER CONFLUENCE ZONE MARKED BY A SURFACE TROUGH ANALYZED ALONG 32N65W 27N71W 25N76W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE WITHIN 160 NM EAST OF THE TROUGH AXIS. A WEAK UPPER LEVEL TROUGH OVER THE EASTERN ATLC SUPPORTS A DISSIPATING COLD FRONT THAT ENTERS THE DISCUSSION AREA NEAR 32N18W...EXTENDING TO 25N28W. POSSIBLE ISOLATED CONVECTION IS WITHIN 30 NM ON EITHER SIDE OF THE FRONT. THE REST OF THE AREA OF DISCUSSION N OF 18N REMAINS UNDER FAIR WEATHER CONDITIONS SUPPORTED BY A DRY AND STABLE UPPER ATMOSPHERE SEEN ON WATER VAPOR IMAGERY. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA