FVXX20 KWBC 251730 . VOLCANIC ASH ADVISORY STATEMENT ISSUED 1730 UTC 25 SEPTEMBER 1999 BY THE WASHINGTON VAAC . SANTA MARIA 99-004 GUATEMALA 14.76N 91.65W . BACKGROUND: SANTA MARIA GUATEMALA (1402-03) SUMMIT HEIGHT 12375FT (3772 M) . SOURCES OF INFORMATION: SURFACE REPORT FROM RETALHULEU. GOES-8 VISIBLE...INFRARED...AND MULTISPECTRAL IMAGERY. . ERUPTION DETAILS: 25/1300 UTC SURFACE OBSERVATION FROM MGRT REPORTED AN ERUPTION OF SANTAGUITO ON THE SOUTH WEST FLANK OF SANTA MARIA. . DETAILS OF ASH CLOUD: ASH CAN NOT BE SEEN IN GOES IMAGERY DUE TO BROKEN CUMILONIMBUS IN THE REGION. IT IS BELIEVED TO BE A LAVA EVENT ONLY. THESE LAVA EVENTS ARE REGULAR FOR SANTAGUITO. THERE IS NO APPARENT HAZARD TO AVIATION ABOVE FL200. . TRAJECTORY: N/A. . HUGHES/NOAA/NESDIS SAB . 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 www.ssd.noaa.gov/VAAC/washington.html (all lower case except /VAAC/) . OUTLOOK: SEE SIGMETS. . THIS WILL BE THE LAST MESSAGE ISSUED FOR THIS EVENT. . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . NNNN