FVXX21 KWBC 212100 . VOLCANIC ASH ADVISORY STATEMENT ISSUED 2100 UTC 21 DEC 1999 BY THE WASHINGTON VAAC . TUNGURAHUA 99-276 ECUADOR 1.47S 78.44W . BACKGROUND: TUNGURAHUA ECUADOR (1502-08) SUMMIT HEIGHT 16480 FT (5023 M) . SOURCES OF INFORMATION: GOES-8 VISIBLE INFRARED AND MULTISPECTRAL IMAGERY. AVIATION UPPER AIR SOUNDING FORECAST. SURFACE REPORT FROM SERB THROUGH GUAYAQUIL MWO . ERUPTION DETAILS: OCCASIONAL EMISSIONS OF ASH AND STEAM TO FL220. . DETAILS OF ASH: A SINGLE SATELLITE IMAGERY AT 1745 UTC SHOWED A POSSIBLE LOW LEVEL ASH PLUME MOVING SOUTHWEST. OTHER SATELLITE IMAGES ARE NOT AVAILABLE. A SURFACE OBSERVATION FROM SERB AS REPORTED BY THE GUAYAQUIL REPORTED ASH AT FL220 MOVING SOUTHWEST. . TRAJECTORY: ASH AT FL220 WOULD MOVE SW AT 15 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. . EFFECTIVE JANUARY 3 2000 AT 0000 UTC... ALL REFERENCES TO LATITUDE AND LONGITUDE IN VOLCANIC ASH ADVISORY STATEMENTS WILL BE IN DEGREES AND MINUTES OF A DEGREE. EXAMPLE: 16.70N 62.20W WILL BE 1642N6212W . THE NEXT STATEMENT WILL BE ISSUED BY 22/0300 UTC. . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . NNNN