000 AXNT20 KNHC 271817 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT THU OCT 27 2011 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1745 UTC. ...SPECIAL FEATURE... HURRICANE RINA HAS BEEN DOWNGRADED TO A TROPICAL STORM AT 27/1500 UTC. THE CENTER OF TROPICAL STORM RINA AT 27/1800 UTC IS NEAR 19.5N 87.1W. RINA IS MOVING NORTHWARD/350 DEGREES 5 KT. RINA IS ABOUT 115 KM/70 MILES TO THE SOUTH OF COZUMEL IN MEXICO...AND ABOUT 170 KM/105 MILES TO THE NORTHEAST OF CHETUMAL IN QUINTANA ROO OF THE YUCATAN PENINSULA OF MEXICO. THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 991 MB. THE MAXIMUM SUSTAINED WIND SPEEDS ARE 60 KT WITH GUSTS TO 75 KT. PLEASE READ THE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/ WMO HEADERS MIATCPAT3/WTNT33 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT3/WTNT23 KNHC FOR MORE DETAILS. UPPER LEVEL SOUTHERLY VERTICAL WIND SHEAR AND ENTRAINMENT OF MIDDLE LEVEL TO UPPER LEVEL DRIER AIR HAVE COMBINED TO BEGIN TO WEAKEN RINA A BIT. THE LOW LEVEL CENTER NOW IS EXPOSED AT THE SOUTHERN EDGE OF A BURST OF DEEP CONVECTIVE PRECIPITATION. NUMEROUS STRONG RAINSHOWERS ARE FROM 19N TO 20.5N BETWEEN 86W AND 88W ALONG THE NORTHEASTERN COAST OF THE YUCATAN PENINSULA. OTHER RAINSHOWERS COVER THE NORTHWESTERN CORNER OF THE CARIBBEAN SEA/THE YUCATAN CHANNEL...AND THE SOUTHEASTERN GULF OF MEXICO TO THE SOUTH OF 25N TO THE EAST OF 88W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH REACHES THE AFRICA COAST NEAR 13N16W NEAR SENEGAL AND GAMBIA. ISOLATED AND DISORGANIZED MODERATE RAINSHOWERS COVER THE ATLANTIC OCEAN TO THE SOUTH OF 10N TO THE EAST OF 35W. ...DISCUSSION... THE GULF OF MEXICO... AN UPPER LEVEL CYCLONIC CIRCULATION CENTER IS MOVING THROUGH EASTERN NEW MEXICO TOWARD THE TEXAS PANHANDLE. THIS CYCLONIC CENTER SUPPORTS A COLD FRONT THAT IS MOVING THROUGH TEXAS TOWARD THE GULF OF MEXICO. THE COLD FRONT IS FORECAST TO MOVE CLOSE TO TROPICAL STORM RINA...WHEN BOTH FEATURES ARE IN THE SOUTHEASTERN GULF OF MEXICO/THE YUCATAN CHANNEL AROUND 48 HOURS INTO THE FUTURE. UPPER LEVEL SOUTHERLY WIND FLOW AND COMPARATIVELY DRIER AIR IN THE WATER VAPOR IMAGERY COVER THE AREA TO THE WEST OF 90W...AND TO THE NORTH OF 28N TO THE EAST OF 90W. UPPER LEVEL ANTICYCLONIC OUTFLOW FROM TROPICAL STORM RINA COVER THE AREA TO THE EAST OF 90W. UPPER LEVEL MOISTURE IS TO THE SOUTH OF 28N TO THE EAST OF 90W. A SURFACE RIDGE PASSES THROUGH 30N78W IN THE ATLANTIC OCEAN TO 29N94W IN THE NORTHWESTERN CORNER OF THE AREA. THE CARIBBEAN SEA... TROPICAL STORM RINA AND ITS WEATHER AND CIRCULATION COVER THE EXTREME NORTHWESTERN CORNER/THE YUCATAN CHANNEL. A SURFACE TROUGH IS ALONG 80W FROM 13N TO 18N. SCATTERED TO NUMEROUS STRONG RAINSHOWERS COVER THE WATERS FROM 14N TO 18N BETWEEN 77W AND 81W. WIDELY SCATTERED MODERATE TO ISOLATED STRONG RAINSHOWERS ARE ELSEWHERE FROM 10N TO 18N BETWEEN 72W AND EASTERN NICARAGUA/EASTERN HONDURAS. THE MONSOON TROUGH PASSES THROUGH 12N74W 11N80W BEYOND 10N IN COSTA RICA. UPPER LEVEL CYCLONIC WIND FLOW COVERS THE EASTERN CARIBBEAN SEA TO THE EAST OF 66W. THIS FLOW IS RELATED TO A TROUGH THAT ORIGINATES IN THE ATLANTIC OCEAN NEAR 15N57W. ISOLATED MODERATE RAINSHOWERS ARE FROM 8N TO 11N BETWEEN 54W AND 64W IN NORTHEASTERN VENEZUELA. THE 24-HOUR RAINFALL TOTAL IN TRINIDAD FOR THE TIME PERIOD ENDING AT 27/1200 UTC WAS 0.37 INCHES. THE ATLANTIC OCEAN... THE UPPER LEVEL ANTICYCLONIC OUTFLOW FROM TROPICAL STORM RINA COVERS THE AREA TO THE WEST OF 75W. THE BROAD LARGE-SCALE WIND FLOW BECOMES CYCLONIC TO THE EAST OF 75W...AND IT SPANS THE ATLANTIC OCEAN TO THE NORTH OF 20N BETWEEN 40W AND 75W. COMPARATIVELY DRIER AIR IN WATER VAPOR IMAGERY IS IN THIS AREA ALSO. THE CYCLONIC FLOW WITH THE TROUGH SUPPORTS A COLD FRONT THAT PASSES THROUGH 32N40W 26N50W TO 24N60W. A SURFACE TROUGH CONTINUES FROM 24N60W TO 23N68W. RAINSHOWERS ARE POSSIBLE WITHIN 90 NM ON EITHER SIDE OF THE LINE THAT PASSES THROUGH 32N39W 26N50W 23N60W 23N70W. A SURFACE RIDGE PASSES THROUGH A 1019 MB HIGH PRESSURE CENTER THAT IS NEAR 32N60W BEYOND 30N78W...INTO THE GULF OF MEXICO. AN UPPER LEVEL TROUGH EXTENDS FROM A CYCLONIC CIRCULATION CENTER THAT IS NEAR 20N38W...TO 15N42W... TOWARD TRINIDAD AND NORTHEASTERN VENEZUELA. SCATTERED MODERATE TO ISOLATED STRONG RAINSHOWERS ARE FROM 20N TO 21N BETWEEN 37W AND 39W AROUND THE 20N38W CYCLONIC CENTER. RAINSHOWERS ARE POSSIBLE ELSEWHERE FROM 16N TO 21N BETWEEN 28W AND 33W...FROM 10N TO 17N BETWEEN 36W AND 43W...AND FROM 8N TO 10N BETWEEN 43W AND 48W. AN UPPER LEVEL TROUGH IS IN AFRICA PASSING THROUGH MOROCCO. THE TROUGH SUPPORTS A DISSIPATING COLD FRONT THAT REACHES THE CANARY ISLANDS. BROKEN TO OVERCAST CLOUDS COVER THE CANARY ISLANDS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ MT