FVXX21 KWBC 250820 . VOLCANIC ASH ADVISORY STATEMENT ISSUED 0800 UTC 25 OCTOBER 1999 BY THE WASHINGTON VAAC . TUNGURAHUA 99-028 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 ...GEOPHYSICAL INSTITUTE. UPPER AIR SOUNDING NEAR THE VOLCANO. . ERUPTION DETAILS: CONTINUOUS VENTING OF ASH AND STEAM. . DETAILS OF ASH: GOES-8 SATELLITE IMAGERY THROUGH 0745 UTC SHOWS DENSE LOW AND MIDDLE LEVEL CLOUDS IN THE VICINITY OF THE VOLCANO MAKING IT IMPOSSIBLE TO DETECT ANY ASH. THE GUAYAQUIL MWO REPORTED ASH FROM THE VOLCANO TO FL280 MOVING SOUTHWEST. THE GEOPHYSICAL INSTITUTE REPORTS HIGH SEISMIC ACTIVITY AND THAT IT IS LIKELY THE VOLCANO WILL CONTINUE TO VENT ASH AND GASES. . TRAJECTORY: UPPER AIR DATA SUGGESTS ANY ASH TO FL280 WOULD MOVE TO THE WEST TO SOUTHWEST AROUND 10 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 AROUND 25/1400 UTC. . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . NNNN