FVXX21 KWBC 142330 . VOLCANIC ASH ADVISORY STATEMENT ISSUED 2330 UTC 14 DEC 1999 BY THE WASHINGTON VAAC . TUNGURAHUA 99-248 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...U.S. NUMERICAL MODEL WIND FORECASTS...GEOPHYSICAL INSTITUTE REPORT AND WIND DATA... . ERUPTION DETAILS: CONTINUOUS VENTING OF LIGHT ASH AND STEAM...OCCASIONAL WEAK TO MODERATE EXPLOSIONS WITH THICKER ASH . DETAILS OF ASH: SATELLITE IMAGERY THROUGH 14/2245 UTC SHOWS EXTENSIVE MULTILAYERED CLOUDINESS WITH SCATTERED SHOWERS AND THUNDERSTORMS IN THE VICINITY OF THE VOLCANO. THERE IS NO ASH PLUME DETECTED IN SATELLITE IMAGERY HOWEVER THE LATEST SIGMET FROM GUAYAQUIL DOES INDICATE ASH TO FL200 OVER THE SUMMIT. HENCE IT IS BELIEVED THAT THERE MAY BE AT LEAST A SMALL ASH PLUME THAT HAS EMBEDDED ITSELF WITHIN THE SURROUNDING CLOUD DECKS. CAUTION IS STRONGLY ADVISED. . TRAJECTORY: ASH FROMT THE SUMMIT TO FL200 WOULD MOVE WEST-SOUTHWEST AT 10 TO 20 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 15/0530 UTC. . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . ORRISON . NNNN