FVXX21 KWBC 240725
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VOLCANIC ASH ADVISORY STATEMENT
ISSUED 0725 UTC 24 DEC 1999 BY THE WASHINGTON VAAC 
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TUNGURAHUA 99-287         ECUADOR 1.47S 78.44W 
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BACKGROUND:    TUNGURAHUA ECUADOR (1502-08)
               SUMMIT HEIGHT 16480 FT (5023 M)
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SOURCES OF INFORMATION: GOES-8 INFRARED AND MULTISPECTRAL
IMAGERY...GEOPHYSICAL INSTITUTE REPORT...0000 UTC AVIATION MODEL
WIND FORECAST...
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ERUPTION DETAILS: INTERMITTENT ASH AND STEAM EMISSIONS
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DETAILS OF ASH: NO ASH CAN BE SEEN IN SATELLITE IMAGERY THROUGH
24/0645 UTC. THERE ARE SCATTERED AREAS OF SHOWERS AND THUNDERSTORMS
ADJACENT TO THE VOLCANO AND THIS IS MAKING IT DIFFICULT TO ASCERTAIN
WHETHER ANY PLUMES TRULY EXIST AT THIS TIME. THERE ARE NO SURFACE
REPORTS OF ASH AT THIS TIME AND SO ANY ACTIVITY IS CURRENTLY
BELIEVED TO BE GENERALLY LIGHT. OCCASIONAL SMALL EXPLOSIONS THAT
HAVE BEEN REPORTED BY THE GEOPHYSICAL INSTITUTE ON A DAILY BASIS
HAVE BEEN TYPICALLY SENDING ASH AND STEAM TO BETWEEN FL180 AND
FL230. 
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A MODERATE EXPLOSION ON THE MORNING OF DECEMBER 23 SENT ASH TO FL300
BUT THE ASH ASSOCIATED WITH THIS IS NO LONGER DETECTABLE AND IS
BELIEVED TO HAVE DISSIPATED.
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TRAJECTORY: ANY ASH AND STEAM BETWEEN FL180 AND FL230 IS EXPECTED TO
MOVE TO THE SOUTH AT 10 TO 15 KNOTS.
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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  
http://www.ssd.noaa.gov/VAAC/washington.html
(all lower case except /VAAC/)
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OUTLOOK:  SEE SIGMETS.
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EFFECTIVE JANUARY 3 2000 AT 0000 UTC... ALL REFERENCES TO LATITUDE
AND LONGITUDE IN VOLCANIC ASH ADVISORY STATEMENTS WILL BE IN DEGREES
AND MINUTES OF A DEGREE.  EXAMPLE: 16.70N 62.20W  WILL BE 1642N6212W
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THE NEXT STATEMENT WILL BE ISSUED BY 24/1330 UTC.
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PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS.
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ORRISON
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NNNN