FVXX22 KWBC 311256 VOLCANIC ASH ADVISORY ISSUED: 2003MAY31/1255Z VAAC: WASHINGTON VOLCANO: ANATAHAN 0804-20 LOCATION: N1621E14540 AREA: MARIANA ISLANDS SUMMIT ELEVATION: 2585 FT (788 M) ADVISORY NUMBER: 2003/088 INFORMATION SOURCE: GOES-9 IMAGERY. GUAM UPPER AIR SOUNDING. ERUPTION DETAILS: CONTINUOUS ASH AND GAS EMISSIONS SINCE MAY 10. OBS ASH DATE/TIME: 31/1202Z OBS ASH CLOUD: ASH NOT IDENTIFIABLE FROM SATELLITE DATA. WINDS SFC/FL100 MOVING NW 10-15 KNOTS. FCST ASH CLOUD +6H: SEE SIGMETS. REMARKS: ASH NOT IDENTIFIABLE IN SATELLITE IMAGERY THROUGH 31/1202Z DUE TO OBSCURING CLOUD COVER AND DARKNESS. THERE IS NO REASON TO BELIEVE THE VOLCANO HAS STOPPED EMITTING ASH SO WE ARE TAKING THE ESTIMATED ASH HEIGHT BACK DOWN ITS MORE ROUTINE LOWER LEVEL OF BELOW FL100. THERE HAVE BEEN NO UPDATED PILOT REPORTS. WE WILL CONTINUE TO CLOSELY MONITOR ANATAHAN AND UPDATE FOR ANY CHANGES. NEXT ADVISORY: WILL BE ISSUED BY 2003MAY31/1900Z. NNNN