FVXX20 KWBC 152200 . VOLCANIC ASH ADVISORY STATEMENT ISSUED 2200 UTC 15 APR 1999 BY THE WASHINGTON VAAC . POPOCATEPETL 99-064 MEXICO 19.02N 98.62W . BACKGROUND: POPOCATEPETL MEXICO (1401-09) SUMMIT HEIGHT 17930 FT (5465 M) . SOURCES OF INFORMATION: GOES-8 VISIBLE IMAGERY. 1200 UTC MEXICO CITY SOUNDING. CENAPRED REPORT. MEXICO CITY MWO... . ERUPTION DETAILS: INITIAL ERUPTION AT 15/1557 UTC. . DETAILS OF ASH CLOUD: NO ASH CLOUD IS DISCERNIBLE IN THE GOES-8 VISIBLE IMAGERY THROUGH 2130 UTC. CENAPRED REPORTED A MEDIUM EXHALATION OCCURRED AT 1557 UTC WHICH LASTED ABOUT 4 MINUTES. ASH WAS REPORTED BETWEEN FL180 AND FL260. NO ADDITIONAL INFORMATION HAS BEEN RECEIVED. . TRAJECTORY: ASH MOVED TOWARD THE ENE. . 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. . THIS IS THE LAST MESSAGE FOR THIS EVENT. . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . NNNN