FVXX21 KWBC 230800 . VOLCANIC ASH ADVISORY STATEMENT ISSUED 0800 UTC 23 OCTOBER 1999 BY THE WASHINGTON VAAC . TUNGURAHUA 99-020 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...U.S. NATIONAL WEATHER SERVICE NUMERICAL WEATHER PREDICTION MODELS . ERUPTION DETAILS: CONTINUOUS VENTING OF ASH AND STEAM . DETAILS OF ASH: THROUGH 0715 UTC ANY ASH CLOUD IS OBSCURED BY THICK METEOROLOGICAL CLOUDS OVER THE COUNTRY. THE GEOPHYSICAL INSTITUTE CONTINUES TO REPORT THAT SEISMIC ACTIVITY REMAINS HIGH AND IT IS LIKELY THAT THE VOLCANO CONTINUES TO VENT ASH AND GASES. . TRAJECTORY: NUMERICAL MODEL FORECASTS VALID AT 23/0600 UTC SUGGEST THAT ANY ASH BETWEEN FL160 AND FL250 WOULD MOVE TOWARD THE WEST TO SOUTHWEST AT 5 TO 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 MESSAGE WILL BE ISSUED AROUND 23/1400 UTC. . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . NNNN