FVXX21 KWBC 180400 VOLCANIC ASH ADVISORY ISSUED 0400 UTC 18 JUL 2000 BY THE WASHINGTON VAAC . TUNGURAHUA 00-837 ECUADOR 0128S 7826W . BACKGROUND: TUNGURAHUA ECUADOR (1502-08) SUMMIT HEIGHT 16480 FT (5023 M) . SOURCES OF INFORMATION: GOES-8 INFRARED AND MULTISPECTRAL IMAGERY. 18/0600 UTC AVIATION MODEL WINDS FORECAST FROM THE 17/1800 UTC MODEL RUN. . ERUPTION DETAILS: GASES WITH OCCASIONAL ASH EMISSIONS. . DETAILS OF ASH: IMAGERY THROUGH 0345 UTC DOES NOT INDICATE THE PRESENCE OF ASH. PILOT AND SURFACE REPORTS FROM 6 HOURS EARLIER DID INDICATE ASH AT OR NEAR THE SUMMIT. . TRAJECTORY: UPPER AIR PATTERNS SUGGEST ANY ASH AT OR NEAR SUMMIT LEVEL TO MOVE WEST AT 5 TO 10 KNOTS. . OUTLOOK: SEE SIGMETS. . THE NEXT MESSAGE WILL BE ISSUED BY 18/1000 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. . HUGHES . NNNN