FVXX21 KWBC 252130 VOLCANIC ASH ADVISORY STATEMENT ISSUED 2130 UTC 25 APR 2000 BY THE WASHINGTON VAAC . TUNGURAHUA 00-487 ECUADOR 0128S 7826W . BACKGROUND: TUNGURAHUA ECUADOR (1502-08) SUMMIT HEIGHT 16480 FT (5023 M) . SOURCES OF INFORMATION: GOES-8 VISIBLE...INFRARED AND MULTISPECTRAL IMAGERY. UPPER WINDS FORECAST FROM THE AVIATION MODEL. THE GEOPHYSICAL INSTITUTE IN QUITO. . ERUPTION DETAILS: OCCASIONAL GAS AND ASH EMISSIONS. . DETAILS OF ASH: THE GEOPHYSICAL INSTITUE REPORTS VOLCANIC ASH OVER THE VOLCANO AT 25/2048 UTC TO FL320. AN AIRCRAFT OBSERVATION REPORTS VOLCANIC ASH OVER THE VOLCANO TO FL260 MOVING WEST. SATELLITE IMAGERY THROUGH 2045 UTC SHOWS A HOT SPOT IN NEAR INFRARED IMAGERY OVER THE VOLCANO AND OCCASIONAL SMALL ASH EMISSIONS MOVING WESTWARD. . TRAJECTORY: UPPER AIR PATTERNS SUGGEST ANY ASH UP TO FL320 WOULD MOVE TO THE WEST AT 15 TO 20 KNOTS. . OUTLOOK: SEE SIGMETS. . THE NEXT STATEMENT WILL BE ISSUED BY 26/0330 UTC. . 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/) . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . KARST . NNNN