FVXX20 KWBC 211620 . VOLCANIC ASH ADVISORY STATEMENT-WATCH ISSUED 1620 UTC 21 FEB 1999 BY THE WASHINGTON VAAC . COLIMA 99-013 MEXICO 19.51N 103.62W . BACKGROUND: COLIMA MEXICO (1401-04) SUMMIT HEIGHT 13451 FT (4100 M) THE COLIMA VOLCANO OBSERVATORY REPORTS THAT THE VOLCANO REMAINS UNSTABLE WITH THE POTENTIAL TO PRODUCE AN ERUPTION CLOUD WITH LITTLE OR NO WARNING. . WE WILL CONTINUE TO MONITOR THE AREA AND IF THERE IS AN ASH CLOUD OBSERVED OR REPORTED AT ANY ALTITUDE A VOLCANIC ASH ADVISORY STATEMENT WARNING WILL BE ISSUED AS SOON AS POSSIBLE. . THE WATCH VAAS IS ISSUED ONLY FOR SEISMICALLY MONITORED VOLCANOES AND BASED ON INFORMATION RECEIVED FROM THE GEOLOGICAL COMMUNITY. A WATCH VAAS WILL BE ISSUED DAILY WHEN INFORMATION IS RECEIVED TO INDICATE THAT A VOLCANO IS RESTLESS AND HAS THE POTENTIAL FOR AN EXPLOSIVE ERUPTION WITH LITTLE OR NO WARNING. NON-EXPLOSIVE LOW LEVEL AND NEAR SUMMIT ACTIVITY MAY BE OCCURRING AT PRESENT. SEE NOAA-ARL HOMEPAGE FOR TEST-VAFTAD AT: HTTP://WWW.ARL.NOAA.GOV/VAFTAD.HTML (ALL LOWER CASE) . THE NEXT WATCH STATEMENT WILL BE ISSUED AROUND 22/1600 UTC. . NNNN