FVXX21 KWBC 271700 VOLCANIC ASH ADVISORY . ISSUED: 2001DEC27/1700Z VAAC: WASHINGTON . VOLCANO: TUNGURAHUA 1502-08 LOCATION: 0128S 7826W AREA: ECUADOR . SUMMIT ELEVATION: 16480 FT (5023 M) . ADVISORY NUMBER: 2001/290 INFORMATION SOURCE: SIGMET FROM GUAYAQUIL METEOROLOGICAL WATCH OFFICE. GOES-8 VISIBLE INFRARED AND MULTISPECTRAL IMAGERY. AVIATION MODEL WIND FORECAST. . ERUPTION DETAILS: ASH OBSERVED AT 27/1500Z. . DETAILS OF ASH CLOUD: A SIGMET INDICATES THAT THE GEOPHYSICAL INSTITUTE OBSERVED ASH AT 1500Z TO FL23O MOVING WEST. SATELLITE IMAGERY THROUGH 1545Z DOES NOT SHOW ASH BUT ASH DETECTION MIGHT BE HINDERED BY THE WEATHER CLOUDS IN THE AREA. . TRAJECTORY: ASH IS MOVING WEST AT ABOUT 10 KNOTS. . OUTLOOK: SEE SIGMETS. . NEXT ADVISORY: WILL BE ISSUED BY 2001DEC27/2300Z. . NNNN