FVXX20 KWBC 010505 . VOLCANIC ASH ADVISORY STATEMENT ISSUED 0505 UTC 01 APR 1999 BY THE WASHINGTON VAAC . SOUFRIERE HILLS 99-077 WEST INDIES 16.72N 62.18W . BACKGROUND: SOUFRIERE HILLS MONTSERRAT (1600-05) SUMMIT HEIGHT 3000 FT (915 M) . SOURCES OF INFORMATION: MONTSERRAT VOLCANO OBSERVATORY. 0000 UTC GUADELOUPE RADIOSONDE. . ERUPTION DETAILS: ERUPTION AT ABOUT 0445 UTC . DETAILS OF ASH CLOUD: THE MONTSERRAT VOLCANO OBSERVATORY REPORTS AN ERUPTION THAT SEEMED LARGER THAN THE OTHER ERUPTIONS SEEN IN THE PAST FEW WEEKS. THEY BELIEVE THAT THE ASH PRODUCED WILL BE ABOVE FL100 BUT COULD NOT DETERMINE A PRECISE HEIGHT BECAUSE OF CLOUDS. THE GOES-8 SATELLITE IS IN ECLIPSE AND THEREFORE NO GOES IMAGERY WILL BE AVAILABLE TO MONITOR THE ASH UNTIL AFTER 0615 UTC. . TRAJECTORY: UPPER AIR PATTERNS SUGGEST THAT ASH BETWEEN FL100 AND FL300 WILL MOVE TOWARD THE EAST OR SOUTHEAST. BETWEEN FL100 AND FL200 ASH WILL MOVE AT 10 TO 25 KNOTS AND BETWEEN FL200 AND FL300 ASH WILL MOVE AT 25 TO 55 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 MESSAGE WILL BE ISSUED AS SOON AS NEW INFORMATION BECOMES AVAILABLE. . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . NNNN