000 AXNT20 KNHC 262352 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED OCT 26 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2345 UTC. ...SPECIAL FEATURE... HURRICANE RINA IS CENTERED NEAR 18.3N 86.2W AT 27/0000 UTC OR ABOUT 150 MI...240 KM SSE OF COZUMEL AND 140 MI...225 KM E OF CHETUMAL MEXICO MOVING NW AT 5 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 979 MB. MAXIMUM SUSTAINED WIND SPEED IS 75 KT WITH GUSTS TO 90 KT. PLEASE SEE 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. SCATTERED STRONG CONVECTION IS FROM 16N-21N BETWEEN 84W-89W. THE OUTER BANDS EXTEND TO 25N BETWEEN 80W-90W. RINA IS FORECAST TO MOVE SLOWLY NORTHWARD AND THEN NORTH-NORTHEASTWARD NEAR THE NORTHEASTERN PORTION OF THE YUCATAN PENINSULA AS AN UPPER-LEVEL TROUGH AND ASSOCIATED COLD FRONT MOVE ACROSS THE SOUTHEASTERN UNITED STATES AND THE GULF OF MEXICO. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA ENTERING THE E TROPICAL ATLC ALONG 13N17W TO 9N20W. WIDELY SCATTERED MODERATE CONVECTION IS FROM THE EQUATOR TO 8N BETWEEN 18W-30W. ...DISCUSSION... GULF OF MEXICO... THE OUTER BANDS OF CONVECTION FROM RINA ARE OVER THE SE GULF ACROSS THE FLORIDA STRAITS AND THE YUCATAN CHANNEL. SEE SPECIAL FEATURES ABOVE FOR MORE DETAILS. OTHERWISE...WATER VAPOR IMAGERY DISPLAYS VERY DRY AIR AND STRONG SUBSIDENCE IN THE MID AND UPPER LEVELS OF THE ATMOSPHERE ACROSS THE GULF THIS EVENING. THIS UPPER AIRMASS IS SUPPRESSING ANY DEEP CONVECTION ELSEWHERE ACROSS THE AREA. MARINE OBSERVATIONS SHOW A VERY LOOSE PRESSURE GRADIENT WITH A LIGHT ESE FLOW...BECOMING SOUTHERLY W OF 92W. THE CONVECTION IN THE SE IS EXPECTED TO INCREASE OVER THE NEXT 24-48 HOURS AS RINA APPROACHES THE NE YUCATAN PENINSULA. CARIBBEAN SEA... HURRICANE RINA IS THE MAIN FOCUS PRODUCING SIGNIFICANT WEATHER ACROSS THE NW WATERS OF THE BASIN. SEE SPECIAL FEATURE DISCUSSION ABOVE FOR MORE DETAILS. A BROAD AREA OF LOW LEVEL MOISTURE MOVES ACROSS THE CENTRAL AND WRN CARIBBEAN NOTICED ON TPW PRODUCT. WITHIN THIS AREA OF DEEP MOISTURE...A SURFACE TROUGH IS ANALYZED FROM 18N74W TO NEAR 12N76W. THE COMBINATION OF LOW LEVEL CONVERGENCE AROUND THE SURFACE TROUGH AND PLENTY OF MOISTURE AVAILABLE IS GENERATING A BROAD AREA OF SCATTERED HEAVY SHOWERS AND THUNDERSTORMS S OF 17N BETWEEN 66W-81W. THIS TROUGH IS BEGINNING TO INTERACT WITH THE MONSOON TROUGH ANALYZED ACROSS THE FAR SW BASIN ALONG COSTA RICA TO NRN COLOMBIA. SHORT RANGE COMPUTER MODELS SUGGEST A WEAK LOW PRESSURE SYSTEM DEVELOPING IN THIS REGION OVER THE NEXT 24 HRS. ATLANTIC OCEAN... THE BROAD CYCLONIC WIND FIELD FROM RINA IS DRAWING MOISTURE ACROSS THE CENTRAL BAHAMAS AND THE FLORIDA STRAITS W OF 73W FROM 23N-25N WITH SCATTERED WEAK SHOWERS DEPICTED FROM MOSAIC DOPPLER RADAR. OTHERWISE...A SURFACE RIDGE COVERS THE WRN ATLC ANCHORED BY A 1020 MB HIGH NEAR 32N72W. WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL TROUGH MOVING ACROSS THE NORTH CENTRAL ATLC WATERS SUPPORTING A COLD FRONT EXTENDING INTO THE AREA ALONG 32N44W TO 27N51W BECOMING DISSIPATING NEAR 24N60W TO 23N65W. THE STRONGEST CONVECTION IS N OF THE DISCUSSION AREA WHERE THE GREATEST DIFFLUENCE ALOFT IS NOTICED. ONLY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE WITHIN 30 NM ON EITHER SIDE OF THE FRONT AXIS FROM 25N-30N. AN UPPER LEVEL LOW IS IN THE CENTRAL TROPICAL ATLC NEAR 19N39W GENERATING A SMALL CLUSTER OF SCATTERED MODERATE CONVECTION FROM 17N-21N BETWEEN 35W-40W. TO THE SW OF THIS AREA OF CONVECTION...A SURFACE 1007 MB LOW IS NEAR 14N44W. A SURFACE TROUGH IS ANALYZED FROM 17N35W ACROSS THE LOW CENTER TO 10N50W. THESE SYSTEM IS PRODUCING SCATTERED SHOWERS AND THUNDERSTORMS FROM 10N-15N BETWEEN 40W-45W. OTHERWISE...A BROAD UPPER RIDGE COVERS THE CENTRAL AND ERN ATLC ANCHORED BY A WEAK 1018 MB HIGH CENTERED NEAR 28N27W PRODUCING FAIR WEATHER ACROSS THE REMAINDER OF THE DISCUSSION AREA. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA