FVXX21 KWBC 210210 . VOLCANIC ASH ADVISORY STATEMENT ISSUED 0210 UTC 21 NOV 1999 BY THE WASHINGTON VAAC . TUNGURAHUA 99-146 ECUADOR 1.47S 78.44W . BACKGROUND: TUNGURAHUA ECUADOR (1502-08) SUMMIT HEIGHT 16480 FT (5023 M) . SOURCES OF INFORMATION: GOES-8 INFRARED AND MULTISPECTRAL IMAGERY... THE GEOFISICO INSTITUTO...1800 UTC AVIATION MODEL UPPER AIR WIND DATA. . ERUPTION DETAILS: CONTINUOUS STEAM AND ASH EMISSIONS AS REPORTED BY THE GEOFISICO INSTITUTO. . DETAILS OF ASH: EXTENSIVE MULTILAYERED CLOUDINESS FROM SHOWER AND THUNDERSTORM ACTIVITY IS CURRENTLY MAKING IT IMPOSSIBLE TO DETECT ANY NEW ASH FROM THE VOLCANO. THE ASH CLOUD FROM EARLIER IN THE DAY WHICH WAS VISIBLE IS NO LONGER DISCERNIBLE AT THIS TIME. HOWEVER THE GEOFISICO INSTITUTO CONTINUES TO REPORT THAT SEISMIC ACTIVITY IS STRONG AND THAT THERE HAS BEEN A CONTINUOUS RELEASE OF ASH AND STEAM. EVEN THOUGH ASH IS NOT DISCERNIBLE AT THIS TIME THERE MAY WELL BE ASH EMBEDDED WITHIN THE CLOUD DECKS. CAUTION IS STRONGLY ADVISED. . TRAJECTORY: THE FOLLOWING ARE THE TRAJECTORIES THAT ANY ASH WOULD TAKE SHOULD IT BE EMBEDDED WITHIN THE MULTILAYERED CLOUDS...POSSIBLE ASH BETWEEN THE SUMMIT AND FL350 WOULD MOVE SOUTHWEST AT 10 TO 20 KNOTS. POSSIBLE ASH BETWEEN FL350 AND FL450 WOULD MOVE TO THE WEST AT 20 TO 40 KNOTS. . REAL TIME SATELLITE IMAGERY ALONG WITH THIS AND OTHER VOLCANIC ASH ADVISORY STATEMENTS 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/) . OUTLOOK: SEE SIGMETS. . THE NEXT STATEMENT WILL BE ISSUED BY 21/0800 UTC. . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . ORRISON . NNNN