FVXX21 KWBC 261800 VOLCANIC ASH ADVISORY ISSUED: 2001MAY26/1800Z VAAC: WASHINGTON . VOLCANO: POPOCATEPETL 1401-09 LOCATION: 1901N 9837W AREA: MEXICO . SUMMIT ELEVATION: 17930 FT (5465 M) . ADVISORY NUMBER: 2001/64 . INFORMATION SOURCE: MEXICO CITY METEOROLOGICAL WATCH OFFICE. GOES-8 VISIBLE..INFRARED AND MULTISPECTRAL IMAGERY. SIX HOUR WIND FORECAST FROM THE 26/1200Z AVIATION MODEL. . ERUPTION DETAILS: STEAM AND ASH EMISSION AT 26/1722Z. . DETAILS OF ASH CLOUD: THE MEXICO CITY METEOROLOGICAL WATCH OFFICE REPORTS AN ASH AND STEAM ERUPTION TO FL230. SATELLITE IMAGERY THROUGH 26/1740Z SHOWS TWO DISTINCT ASH PLUMES. A HIGH LEVEL PLUME ESTIMATED TO BE AT FL23O IS MOVING OFF TO THE NORTHEAST WHILE A LOWER LEVEL PLUME ESTIMATED TO BE AT SUMMIT LEVEL IS MOVING TO THE SOUTHWEST. . TRAJECTORY: ASH AT FL230 WILL MOVE TOWARDS THE NORTHEAST AT 15-20 KNOTS. ASH AT FL180 WILL MOVE TOWARDS THE SOUTHWEST AT 15-20 KNOTS. . OUTLOOK: SEE SIGMETS. . THE NEXT MESSAGE WILL BE ISSUED BY 27/000OZ. . REAL TIME SATELLITE IMAGERY AND VOLCANIC ASH ADVISORIES OFTEN ACCOMPANIED BY A MAP DEPICTING ASH LOCATION ARE AVAILABLE AT INTERNET URL ADDRESS HTTP://WWW.SSD.NOAA.GOV/VAAC/WASHINGTON.HTML (ALL LOWER CASE EXCEPT /VAAC/) . PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS. . WALTER/ORRISON . NNNN