FVXX21 KWBC 211700 VOLCANIC ASH ADVISORY ISSUED 1700 UTC 21 JUL 2000 BY THE WASHINGTON VAAC . TUNGURAHUA 00-851 ECUADOR 0128S 7826W . BACKGROUND: TUNGURAHUA ECUADOR (1502-08) SUMMIT HEIGHT 16480 FT (5023 M) . SOURCES OF INFORMATION: GOES-8 VISIBLE AND INFRARED AND MULTISPECTRAL IMAGERY. WINDS FORECAST FROM THE AVIATION MODEL. GEOPHYSICAL INSTITUTE REPORT. . ERUPTION DETAILS: GASES WITH OCCASIONAL ASH EMISSIONS. . DETAILS OF ASH: SATELLITE IMAGERY THROUGH 21/1615 UTC SHOWS LOW AND MID LEVEL CLOUDINESS IN THE VICINITY OF THE VOLCANO MAKING IT DIFFICULT TO DETECT ASH. . TRAJECTORY: ANY ASH ABOUT SUMMIT LEVEL WOULD MOVE TO THE WEST OR SOUTHWEST AT 10 TO 15 KTS. . OUTLOOK: SEE SIGMETS. . THE NEXT MESSAGE WILL BE ISSUED BY 21/2300 UTC. . REAL TIME SATELLITE IMAGERY ALONG WITH THIS AND OTHER VOLCANIC ASH ADVISORIES OFTEN ACCOMPANIED BY A MAP DEPICTING ASH LOCATION ARE AVAILABLE AT INTERNET URL ADDRESS http://www.ssd.noaa.gov/VAAC/washington.html (all lower case except /VAAC/) . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . KARST . NNNN