FVXX21 KWBC 251200 VOLCANIC ASH ADVISORY STATEMENT ISSUED 1200 UTC 25 APR 2000 BY THE WASHINGTON VAAC . TUNGURAHUA 00-485 ECUADOR 0128S 7826W . BACKGROUND: TUNGURAHUA ECUADOR (1502-08) SUMMIT HEIGHT 16480 FT (5023 M) . SOURCES OF INFORMATION: GOES-8 VISIBLE...INFRARED AND MULTISPECTRAL IMAGERY. 25/1200 UTC FORECAST UPPER WINDS FROM THE 25/0600 UTC AVN MODEL. THE GEOPHYSICAL INSTITUTE IN QUITO. . ERUPTION DETAILS: OCCASIONAL GAS AND ASH EMISSIONS. . DETAILS OF ASH: GOES-8 IMAGERY THROUGH 1145 UTC SHOWS BROKEN LOW TO MID LEVEL CLOUDS COVERING THE VOLCANO MAKING ASH DETECTION DIFFICULT. THE GEOPHYSICAL INSTITUTE REPORTS THAT SEISMIC LEVELS HAVE BEEN NORMAL BUT THERE HAS BEEN SOME SMALL ASH EMISSIONS IN THE PAST 24 HOURS. TUNGURAHUA REMAINS IN A VERY ACTIVE STATE AND COULD PRODUCE AN ERUPTION AT ANYTIME. GOES-8 WILL BE IN A RAPID SCAN MODE FROM 1626 TO 2026 UTC TO SUPPORT NASA OPERATIONS. . TRAJECTORY: UPPER AIR PATTERNS SUGGEST ANY ASH UP TO FL250 WOULD MOVE WEST SOUTHWEST AT 10 TO 15 KNOTS. . OUTLOOK: SEE SIGMETS. . THE NEXT STATEMENT WILL BE ISSUED BY 25/1800 UTC. . 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/) . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . HUGHES . NNNN