FVXX20 KWBC 211320
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VOLCANIC ASH ADVISORY STATEMENT
ISSUED 1320 UTC 21 JULY 1999 BY THE WASHINGTON VAAC 
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SOUFRIERE HILLS 99-184    WEST INDIES 16.7N 62.2W
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BACKGROUND:    SOUFRIERE HILLS MONTSERRAT (1600-05)
               SUMMIT HEIGHT 3000 FT (915M)
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SOURCES OF INFORMATION: GOES-8 VISIBLE AND MULTISPECTRAL IMAGERY
THROUGH 21/1215 UTC.  21/1200 UTC PRINSES JULIANA RADIOSONDE. 
ROOSEVELT ROADS NAS, PUERTO RICO.

ERUPTION DETAILS:  ERUPTION OCCURRED AT ABOUT 20/0910 UTC.
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DETAILS OF ASH CLOUD: A LARGE AREA OF ASH WAS DETECTED IN THE FIRST
VISIBLE IMAGES OF THE DAY.  THE ASH WAS BOUNDED ROUGHLY BY POINTS
17.8N68.9W 19.0N65.6W 25.2N64.1W 25.4N57.3W 17.4N66.8W 17.4N68.9W
17.8N68.9W AT 1215 UTC. DURING THE LAST TWO HOURS THE ROOSEVELT ROADS
NAS IN PUERTO RICO HAS REPORTED VOLCANIC ASH IN THEIR SURFACE
OBSERVATIONS. THE MAXIMUM HEIGHT OF THE ASH TOPS WAS ESTIMATED UP TO
FL400 TO THE NORTHEAST OF PUERTO RICO WHILE ASH TOPS WERE ESTIMATED TO
BE BELOW FL100 OVER AND TO THE SOUTH AND WEST OF PUERTO RICO. 
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TRAJECTORY: ASH BELOW FL100 WAS MOVING WEST BETWEEN 10 AND 20 KNOTS. 
ASH BETWEEN FL100 AND FL250 WAS MOVING NORTH NORTHWEST BETWEEN 10 AND
15 KNOTS.  ASH BETWEEN FL250 AND FL400 WAS MOVING NORTH NORTHEAST
BETWEEN 15 AND 20 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
www.ssd.noaa.gov/VAAC/washington.html
(all lower case except /VAAC/)
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OUTLOOK:  SEE LATEST SIGMETS AND VAFTAD.
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THE NEXT MESSAGE WILL BE ISSUED BY 21/1930 UTC.
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PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS.
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NNNN
"Attached Graphic Map Depicting Ash" 

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