FVXX21 KWBC 130730 . VOLCANIC ASH ADVISORY STATEMENT ISSUED 0730 UTC 13 DEC 1999 BY THE WASHINGTON VAAC . TUNGURAHUA 99-241 ECUADOR 1.47S 78.44W . BACKGROUND: TUNGURAHUA ECUADOR (1502-08) SUMMIT HEIGHT 16480 FT (5023 M) . SOURCES OF INFORMATION: GOES-8 INFRARED AND MULTISPECTRAL IMAGERY...U.S. NUMERICAL MODEL WIND FORECASTS. . ERUPTION DETAILS: CONTINUOUS EMISSION OF ASH AND STEAM. . DETAILS OF ASH: NO ASH COULD BE DETECTED IN IMAGERY THROUGH 0645 UTC. MID TO HIGH LEVEL CLOUDS FROM A CONVECTIVE LINE TO THE EAST MIGHT BE MASKING ANY ASH BEING EMITTED FROM TUNGURAHUA. THE VOLCANO REMAINS IN A VERY RESTLESS STATE WITH POSSIBLE EXPLOSIVE ERUPTIONS AT ANYTIME. . TRAJECTORY: UPPER AIR WIND FORECASTS FROM NUMERICAL MODELS SUGGEST ANY ASH UP TO FL300 WOULD MOVE NORTHWEST AT 5 TO 10 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 AND VAFTAD. . 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 13/1330 UTC. . HUGHES/NOAA/NESDIS/SAB . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . NNNN