FVXX20 KWBC 131700
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VOLCANIC ASH ADVISORY STATEMENT
ISSUED 1700 UTC 13 JAN 1999 BY THE WASHINGTON VAAC
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SOUFRIERE HILLS 99-009    WEST INDIES 16.72N 62.18W  
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BACKGROUND:    SOUFRIERE HILLS MONTSERRAT (1600-05)
               SUMMIT HEIGHT 3000 FT (915 M)
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SOURCES OF INFORMATION: GOES-8 VISIBLE...INFRARED...AND MULTISPECTRAL
IMAGERY. MONTSERRAT VOLCANO OBSERVATORY. 1200 UTC GUADELOUPE SOUNDING.
SURFACE OBSERVATIONS.
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ERUPTION DETAILS: 2 ERUPTIONS OCCURRING AROUND 13/1035 UTC.
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DETAILS OF ASH CLOUD: GOES IMAGERY THROUGH 1515 UTC SHOWS THE ASH FROM
THIS MORNINGS ERUPTION TO BE MOVING IN THREE DIRECTION. THE ASH MOTION
TO THE SOUTH IS A BIT OF A MYSTERY TO US. THE UPPER AIR DATA FROM THE
REGION DOES NOT SUPPORT THIS MOTION SO GIVING IT A GOOD HEIGHT
ASSIGNMENT IS DIFFICULT. THE ASH CLOUD TO THE SOUTH HAS MOVED ROUGHLY
95KM (51NMI) SOUTH FROM THE SUMMIT AND IS BOUNDED BY POINTS 16.6N62.0W 
16.3N62.3W 15.9N62.3W 15.9N61.8W 16.5N61.8W. WE BELIEVE THE ASH MAY BE
HAS HIGH AS FL550 FOR THIS PORTION OF THE ASH CLOUD BUT THIS IS YET
UNCONFIRMED. THE PORTION OF THE ASH CLOUD THAT MOVED WEST FROM THE
ISLAND IS ESTIMATED AT AND BELOW FL130. THE LEADING EDGE IS THICK ASH
AND BECOMES MORE TRANSPARENT CLOSER TO THE ISLAND. IT IS ROUGHLY 188KM
(101NMI) FROM THE SUMMIT AND IS BOUNDED BY POINTS 16.4N62.4W 
16.8N64.0W 17.3N63.9W 17.3N63.2W 16.9N63.1W 16.9N62.1W. THE LAST AREA
IS MOVING TO THE NORTHEAST FROM THE ISLAND AROUND FL250 IS NOW ROUGHLY
130 KM FROM THE SUMMIT. THIS ASH CLOUD IS RATHER THIN AND BECOMING MORE
FAINT WITH TIME. THIS AREA IS ROUGHLY 25KM (14NMI) WIDE BETWEEN POINTS
16.3N62.3W AND 17.5N61.2W. 
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TRAJECTORY: THE ASH CLOUD AT AND BELOW FL130 IS MOVING WEST AROUND 15
TO 20 KNOTS AND THE WESTERN TIP IS MOVING SLIGHTLY NORTH OF WEST AT  10
TO 15 KNOTS. THE FAINT ASH CLOUD BETWEEN FL200 AT FL250 IS MOVING
NORTHEAST AROUND 15 KNOTS. THE ASH CLOUD MOVING TO THE SOUTH MAY BE
AROUND FL500 AND FL550 AND IS MOVING SOUTH AROUND 10 TO 15 KNOTS .
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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/messages.html
(all lower case except /VAAC/)
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OUTLOOK:  SEE LATEST SIGMETS AND VAFTAD.
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THE NEXT MESSAGE FOR THIS EVENT WILL BE ISSUED BY 13/2300 UNLESS
CONDITIONS CHANGE.
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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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