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Ash Information

ARE YOU EXPERIENCING ASHFALL?

If so please click the link below and report ashfall to HVO.

Reports of ashfall are important to us; we use your observations to assess the character and size of an eruption plume. We report these data to the National Weather Service so they can keep their Ashfall warnings current. Additionally, reports of NO ashfall during an eruption with expected ashfall are also important to us. Thank you for your participation in volcano science!

Report ashfall observations here.

ASH3D: Ashfall Forecast for Hypothetical Eruption

This ashfall model is currently being run to reflect a significant explosive eruption from the Halemaumau crater similar to the event that occurred on May 17, 2018. It is updated twice daily with new wind information. In the event of a similar size event, this graphic will show the likely ash fallout result.



  • This ashfall graphic is the output of a mathematical model of volcanic ash transport and deposition on the ground (Ash3D, USGS).
  • This model shows expected ashfall accumulation (deposit thickness) for actual or hypothetical eruptions.
  • HVO produces this graphic when a volcano is restless by assuming a reasonable hypothetical eruption, in order to provide a pre-eruptive forecast of areas likely to be affected. During an eruption, HVO updates the forecast with actual observations (eruption start time and duration, plume height) as they become available.
  • Ash3d deposit calculations are calibrated for explosive eruptions in Alaska and are not optimized for the current style of activity at the summit of Kīlauea.
  • Colored contour lines represent points of equal ash thickness on the ground. Small accumulations of ash may occur beyond the "Trace" contour. Actual deposit thickness may vary from the forecast as the modelled points are based on our best estimates. Thickness terms are explained here.
  • This graphic does not show ash cloud movement in the atmosphere; please refer to the other graphics for ash cloud forecasts.
  • For more information about ASH3D, see USGS Open-File Report 2013-1122.

Citizen Science Opportunity - Collect volcanic ash for HVO

Thank you for assisting the USGS with the analysis of ash being deposited by the current activity at the Halema‘uma‘u Crater. The analysis of these samples will assist the USGS in determining the potential risk to human health, agriculture and the environment. Click the following links to find out how to collect samples and where to send them!

Ash Collection Instructions
Ash Collection Data Sheet with Contact Info