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You are here: Home > Current Volcanic Activity > Shishaldin > NOAA Trajectory Model

  • This trajectory graphic is the output of a mathematical model showing wind direction and speed at different altitudes above sea level (HYSPLIT, NOAA). It does not contain information about ash emissions from the volcano.
  • Colored lines show the direction an ash cloud emanating from a point source (the volcano) would travel at different altitudes in feet above ground level. A given eruption cloud may not reach all altitudes shown.
  • Symbols are spaced one hour apart and reflect the forecast speed of the ash cloud.
  • This model is updated every 6 hours.
  • UTC to AKDT conversion (Alaska Daylight Time):
    0000 UTC = 4:00 PM AKDT on the previous day as UTC
    0600 UTC = 10:00 PM AKDT on the previous day as UTC
    1200 UTC = 4:00 AM AKDT on the same day as UTC
    1800 UTC= 10:00 AM AKDT on the same day as UTC

  • For more information about HYSPLIT see: https://www.ready.noaa.gov/READY_traj_alaska.php

During an actual eruption, see National Weather Service forecasts of airborne ash hazard to aircraft (SIGMETS: https://weather.gov/aawu/ and Volcanic Ash Advisories: https://weather.gov/vaac) as well as forecasts of ash fall: https://weather.gov/afc.
URL: www.avo.alaska.edu/activity/ash3d/hysplit.php
Page modified: April 22, 2019 11:10
Contact Information: AVO Web Team

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