FVXX22 KWBC 152330
VOLCANIC ASH ADVISORY STATEMENT-TIME CORRECTION FOR NEXT VAAS
ISSUED 2330 UTC 15 DEC 1999 BY THE WASHINGTON VAAC 
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SAN CRISTOBAL 99-018 NICARAGUA 12.7N 87.0W 
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BACKGROUND:    SAN CRISTOBAL NICARAGUA (1404-02)
               SUMMIT HEIGHT 5725 FT (1745 M)
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SOURCES OF INFORMATION: GOES-8 VISIBLE..INFRARED AND MULTISPECTRAL
IMAGERY...1200 UTC AVIATION MODEL SOUNDING DATA...
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ERUPTION DETAILS: LIGHT VENTING OF GASES AND POSSIBLY
ASH...SATELLITE IMAGERY SUGGESTS THAT IT MAY HAVE BEGUN AS EARLY
1500 UTC AND THE SIZE OF THE CURRENT THIN PLUME WOULD IMPLY THIS.
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DETAILS OF ASH CLOUD: THE VISIBLE SATELLITE IMAGERY THROUGH 15/2245
UTC COMBINED WITH THE LOW SUN ANGLE IS REVEALING WHAT MAY BE A THIN
LAYER OF POSSIBLY ASH OR GASES PUSHING FROM THE SUMMIT OF SAN
CRISTOBAL AND OFF TO THE WEST. THERE HAVE BEEN NO SURFACE REPORTS OF
ANY ERUPTIONS OR THAT OF ANY ASH. MULTISPECTRAL AND INFRARED IMAGERY
DO NOT SUGGEST ANY ASH EITHER BUT THIS GIVES SUPPORT TO A LOW-LEVEL
PLUME. THE POSSIBLE ASH AND GASES ARE ESTIMATED TO BE UP TO FL080
AND CAN NOW BE SEEN PUSHING A CONSIDERABLE DISTANCE TO THE WEST.
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AT 15/2245 UTC THERE IS A THIN PLUME OF ASH AND/OR GASES EXTENDING
300 KM (162 NMI) TO THE POINT 11.52N 89.48W. THIS PUTS THE PLUME
WELL OUT OVER THE EASTERN PACIFIC OCEAN. OVER THE OCEAN THE PLUME IS
ABOUT 92 KM (50 NMI) WIDE. WHILE THE PLUME IS THIN IN NATURE IT IS
EXPANSIVE AND SO CAUTION IS STRONGLY ADVISED.
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TRAJECTORY: THE GASES AND POSSIBLE ASH ARE SEEN MOVING TO THE WEST-SOUTHWEST NOW AT 10 TO 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.
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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 16/0530 UTC.
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PLEASE REFER TO SIGMETS FOR CURRENT WARNINGS.
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ORRISON
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NNNN"Attached Graphic Map Depicting Ash" 

"Graphic Map Depicting Ash"