TROPICAL DISTURBANCE ADVISORY NUMBER A12 ISSUED FROM RSMC NADIDec 13/1953 UTC 2012 UTC.SEVERE TROPICAL CYCLONE EVAN CENTRE 970HPA CATEGORY 3 WAS LOCATEDNEAR 13.4S 171.6W AT 131800 UTC. POSITION FAIR BASED ON HR GMSIR/VIS IMAGERY AND PERIPHERAL SURFACE REPORTS. CYCLONE MOVINGNORTH-NORTHWEST AT ABOUT 03 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDSNEAR THE CENTRE ESTIMATED AT ABOUT 80 KNOTS. EXPECT WINDS OVER 63 KNOTS WITHIN 20 NAUTICAL MILES OF CENTRE, OVER 47 KNOTS WITHIN 25 NAUTICAL MILES OF CENTRE EXPECT WINDS OVER 33 KNOTS WITHIN 60 NAUTICAL MILES IN THE NEQUADRANT AND WITHIN 40 NAUTICAL MILES IN THE SE QUADRANT AND WITHIN 30 NAUTICAL MILES IN THE SW QUADRANT AND WITHIN 45 NAUTICAL MILES IN THE NW QUADRANT. DEEP CONVECTION PERSISTENT PAST 12 HOURS. CYCLONE LIES UNDER AN UPPERDIFFLUENT REGION. OUTFLOW GOOD TO THE SOUTH AND NORTH. SYSTEM LIES INA LOW SHEARED ENVIRONMENT. SST AROUND 30 DEGREES CELCIUS. SYSTEM ISCURRENTLY BEING STEERED TO THE NORTH-NORTHWEST BY A DEEP LAYER MEANSOUTH-SOUTHEAST. DVORAK ANALYSIS BASED ON EMBD CENTRE CMG SURROUNDYIELDING DT OF 5.0. MET = 5.0, PT = 5.0. FT BASED ON DT. THUS, T5.0/5.0/D1.5/24HRS.