FVXX21 KWBC 172000 VOLCANIC ASH ADVISORY ISSUED: 2001SEP17/2000 VAAC: WASHINGTON . VOLCANO: TUNGURAHUA 1502-08 LOCATION: 0128S 7826W AREA: ECUADOR . SUMMIT ELEVATION: 16480 FT (5023 M) . ADVISORY NUMBER: 2001/252 . INFORMATION SOURCE: GOES-8 VISIBLE...INFRARED AND MULTISPECTRAL IMAGERY. WIND FORECAST FROM THE AVIATION MODEL. GUAYAQUIL METEOROLOGICAL WATCH OFFICE. . ERUPTION DETAILS: OCCASIONAL NEAR SUMMIT ASH FLOW. . DETAILS OF ASH CLOUD: SATELLITE IMAGERY THROUGH 1915Z SHOWS BROKEN LOW AND MID LEVEL CLOUDS OVER THE VOLCANO MAKING IT DIFFICULT TO DETECT ANY ASH. ASH WAS LAST REPORTED BY THE GEOPHYSICAL INSTITUTE AT 16/2250Z. THE VOLCANO REMAINS UNSTABLE AND MAY ERUPT AT ANY TIME. . TRAJECTORY: ASH UP TO FL260 WILL MOVE TOWARDS THE NORTHWEST AT 15 TO 20 KNOTS. . OUTLOOK: SEE SIGMETS. . THE NEXT ADVISORY WILL BE ISSUED BY 18/0200Z. . INTERNET URLS... MESSAGE LISTSERV WWW.SSD.NOAA.GOV/VAAC/SUBSCRIBE.HTML MESSAGES GRAPHICS AND IMAGERY WWW.SSD.NOAA.GOV/VAAC/WASHINGTON.HTML (ALL LOWERCASE EXCEPT /VAAC/) . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . KARST . NNNN