FVXX20 KWBC 241500 . VOLCANIC ASH ADVISORY STATEMENT ISSUED 1500 UTC 24 NOV 1999 BY THE WASHINGTON VAAC . GUAGUA PICHINCHA 99-105 ECUADOR 0.17S 78.60W . BACKGROUND: GUAGUA PICHINCHA ECUADOR (1502-02) SUMMIT HEIGHT 15695 FT (4784 M) . SOURCES OF INFORMATION: GOES-8 VISIBLE INFRARED AND MULTISPECTRAL IMAGERY...THE INSTITUTO GEOFISICO IN QUITO...00 UTC AVIATION MODEL WIND FORECAST...SIGMET FROM GUAYAQUIL METEOROLOGICAL WATCH OFFICE . ERUPTION DETAILS: THE INSTITUTO GEOFISICO INDICATES THAT SOME DOME COLLAPSES ARE PRODUCING SMALL ASH CLOUDS. . DETAILS OF ASH CLOUD: SMALL ASH CLOUDS MAINLY LOCATED NEAR THE SUMMIT ARE REPORTED BY THE INSTITUTO GEOFISICO TO OCCASIONALLY MOVE TOWARD AND REACH QUITO. ASH CLOUDS ARE REPORTED TO MOST OFTEN MOVE TOWARD THE WEST. IN THE SIGMET ASH HEIGHT IS ESTIMATED TO BE AT ABOUT FL220. SATELLITE IMAGERY THROUGH 1415 UTC DOES NOT SHOW ANY ASH BUT THIS COULD BE DUE TO THE NUMEROUS WEATHER CLOUDS IN THE AREA OBSCURING ASH. . TRAJECTORY: WINDS SEEM TO BE LIGHT AND VARIABLE BETWEEN FL220 AND FL160. UPPER AIR PATTERNS SUGGEST THAT ASH WILL MOVE AT LESS THAN 8 KNOTS AND ASH HAS MOST FREQUENTLY BEEN OBSERVED MOVING TOWARD THE WEST. . 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. . THE NEXT STATEMENT WILL BE ISSUED BY 24/2100 UTC. . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . NNNN