FVXX21 KWBC 041330 VOLCANIC ASH ADVISORY ISSUED 1330 UTC 04 SEP 2000 BY THE WASHINGTON VAAC . TUNGURAHUA 00-1036 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 THE AVIATION MODEL. SIGMET FROM GUAYAQUIL METEOROLOGICAL WATCH OFFICE. . ERUPTION DETAILS: GAS AND ASH EMISSIONS. . DETAILS OF ASH: NO ASH CAN BE DETECTED IN SATELLITE IMAGERY THROUGH 04/1245 UTC ALTHOUGH THERE IS EXTENSIVE COVER IN THE VICINITY OF THE SUMMIT. THE GEOPHYSICAL INSTITUTE REPORTED 1 WEAK AND 1 MODERATE EXPLOSIONS OVER THE PAST FEW HOURS WITH AN ESTIMATED APPROXIMATE MAXIMUM HEIGHT OF FL220. . TRAJECTORY: UPPER AIR PATTERNS SUGGEST THAT ANY ASH BETWEEN THE SUMMIT AND FL220 WOULD MOVE TO THE WEST TO WEST-SOUTHWEST ABOUT 10-15 KNOTS. . OUTLOOK: SEE SIGMETS. . THE NEXT ADVISORY WILL BE ISSUED BY 04/1930 UTC. . REAL TIME SATELLITE IMAGERY AND 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