FVXX20 KWBC 210430 . VOLCANIC ASH ADVISORY STATEMENT ISSUED 0430 UTC 21 MAR 1999 BY THE WASHINGTON VAAC . SOUFRIERE HILLS 99-050 WEST INDIES 16.72N 62.18W . BACKGROUND: SOUFRIERE HILLS MONTSERRAT (1600-05) SUMMIT HEIGHT 3000 FT (915 M) . SOURCES OF INFORMATION: GOES-8 INFRARED AND MULTISPECTRAL IMAGERY MONTSERRAT VOLCANO OBSERVATORY AND GUADELOUPE 21/0000 UTC SOUNDING. . ERUPTION DETAILS: ASH PRODUCING EVENT AROUND 20/2145 UTC. . DETAILS OF ASH CLOUD: SATELLITE IMAGERY THROUGH 0402 UTC DOES NOT INDICATE ANY ASH CLOUD. THE AREA IS CURRENTLY COVERED WITH HIGH LEVEL CIRRUS CLOUDS. THE PREVIOUS ASH CLOUD MOVED TO THE NORTHERN PART OF GUADELOUPE AND DISSIPATED AROUND 21/0000 UTC. . TRAJECTORY: THE GUADELOUPE SOUNDING SUGGEST THAT ASH BELOW FL100 WOULD MOVE TO THE SOUTH-SOUTHWEST AT LESS THAN 10 KNOTS. ASH BETWEEN FL100 AND FL200 WOULD MOVE TO THE SOUTHEAST AROUND 15-20 KNOTS. . THIS AND OTHER VOLCANIC ASH ADVISORY STATEMENTS OFTEN ACCOMPANIED BY A MAP DEPICTING ASH LOCATION ARE AVAILABLE AT INTERNET URL ADDRESS www.ssd.noaa.gov/VAAC/messages.html (all lower case except /VAAC/) . OUTLOOK: SEE SIGMETS. . THE NEXT STATEMENT WILL BE ISSUED AROUND 21/1030. . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . NNNN