FVXX21 KWBC 161715 VOLCANIC ASH ADVISORY ISSUED 1715 UTC 16 SEP 2000 BY THE WASHINGTON VAAC . TUNGURAHUA 00-1085 ECUADOR 0128S 7826W . BACKGROUND: TUNGURAHUA ECUADOR (1502-08) SUMMIT HEIGHT 16480 FT (5023 M) . SOURCES OF INFORMATION: GOES-8 VISIBLE...INFRARED...AND MULTISPECTRAL IMAGERY. 16/1800 UTC FORECAST UPPER WINDS FROM THE 16/1200 UTC AVIATION MODEL. THE GEOPHYSICAL INSTITUTE IN QUITO. . ERUPTION DETAILS: OCCASIONAL STEAM AND ASH EMISSIONS. . DETAILS OF ASH: GOES-8 IMAGERY THROUGH 1715 UTC DOES NOT INDICATE THE PRESENCE OF ASH. THERE HAS BEEN NO ASH DETECTION IN THE PAST 48 HOURS...THUS CURRENT ADVISORIES WILL BE SCALED BACK INTO A WATCH. . ...AVIATION INTERESTS ARE REMINDED THAT TUNGURAHUA REMAINS VERY ACTIVE AND HAS A HISTORY OF PRODUCING OCCASIONAL NEAR SUMMIT ASH. TYPICAL ASH MOVEMENT IS TO THE WEST AT UNDER 20 KNOTS... . TRAJECTORY: UPPER AIR PATTERNS SUGGEST ANY ASH AT OR NEAR SUMMIT LEVEL TO MOVE WEST AT 15 TO 20 KNOTS. . OUTLOOK: SEE SIGMETS. . ***THIS WILL BE THE LAST IMMEDIATE ADVISORY ON THIS EVENT UNLESS ACTIVITY INCREASES AGAIN. THE NEXT ADVISORY WILL BE A WATCH ISSUED 17/1700 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. . HUGHES . NNNN