FVXX20 KWBC 121921 VOLCANIC ASH ADVISORY ISSUED: 2003SEP12/1920Z VAAC: WASHINGTON VOLCANO: TUNGURAHUA 1502-08 LOCATION: S0128W07826 AREA: ECUADOR SUMMIT ELEVATION: 16480 FT (5023 M) ADVISORY NUMBER: 2003/236 INFORMATION SOURCE: GOES-12 IMAGERY. GUAYAQUIL MWO SIGMET. GFS MODEL WINDS FORECAST. GEOPHYSICAL INSTITUTE. ERUPTION DETAILS: EMISSION AT 11/0055Z OBS ASH DATE/TIME: 12/1845Z. OBS ASH CLOUD: ASH NOT IDENTIFIABLE FROM SATELLITE DATA. WINDS FL100/270 MOVING W TO SW 10 to 15 KNOTS. FCST ASH CLOUD+6H: SEE SIGMETS. REMARKS: THE LATEST OBSERVATION OF ASH BY THE GEOPHYSICAL INSTITUTE WAS AT 12/1820Z ESTIMATED TO AROUND FL230 MOVING WEST. AN AIRCRAFT REPORT AT 12/1830Z ESTIMATED ASH TO FL260 MOVING SOUTHWEST. IN IMAGERY AT 12/1845Z THERE IS NO ASH DETECTED HOWEVER A SHORT WHITE MOUNTAIN WAVE CLOUD CAN BE SEEN EXTENDING WEST FROM THE SUMMIT. THIS LACK OF ASH DETECTION MAY BE DUE TO MORE STEAM THAN ASH IN THE PLUME. NEXT ADVISORY: WILL BE ISSUED BY 2003SEP13/0130Z. NNNN