FVXX21 KWBC 181230 VOLCANIC ASH ADVISORY ISSUED 1230 UTC 18 JUN 2000 BY THE WASHINGTON VAAC . TUNGURAHUA 00-712 ECUADOR 0128S 7826W . BACKGROUND: TUNGURAHUA ECUADOR (1502-08) SUMMIT HEIGHT 16480 FT (5023 M) . SOURCES OF INFORMATION: GOES-8 VISIBLE INFRARED AND MULTISPECTRAL IMAGERY. WIND FORECAST FROM AVIATION MODEL. SIGMET FROM GUAYAQUIL METEOROLOGICAL WATCH OFFICE. . ERUPTION DETAILS: OCCASIONAL GAS AND ASH EMISSIONS. . DETAILS OF ASH: A GUAYAQUIL SIGMET INDICATES THAT THE GEOPHYSICAL INSTITUTE OBSERVED ASH TO FL250 OVER THE VOLCANO AT 18/0602 UTC. NO ASH CAN BE SEEN IN SATELLITE IMAGERY THROUGH 18/1145 UTC BECAUSE OF THE EXTENSIVE WEATHER CLOUDS COVERING THE AREA. . TRAJECTORY: UPPER AIR PATTERNS SUGGEST THAT ANY ASH FROM THE SUMMIT TO FL250 WOULD MOVE TOWARD THE WEST OR WEST SOUTHWEST AT 12 TO 20 KNOTS. . OUTLOOK: SEE SIGMETS. . THE NEXT MESSAGE WILL BE ISSUED BY 18/1830 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. . NNNN