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Recent Industry News


Upcoming Association Meeting

April 24-27, 2018

Join us in beautiful Estes Park, CO April 24-27, 2018 for the Annual Weather Modification Association Conference at The Stanley Hotel. Listed on the National Register of Historic Places and an easy hour drive from Denver, this place is sure to impress. For more information about the conference and hotel accommodations, please visit the meetings page. See you there!

What is Cloud Seeding?

A few of Our Most Popular Questions

Weather Modification can be both planned, as is the case in cloud seeding, or inadvertent, for example, when pollution affects visibility. Planned (deliberate) weather modification is also commonly know as cloud seeding, cloud modification, or atmospheric water management.

How Does It Work?

Cloud seeding, or commonly referred to as weather modification, is the treatment of individual clouds or cloud systems in an attempt to achieve a desired beneficial effect, including fog and hail mitigation, and additional precipitation in the form of either rain or snow. Cloud seeding is conducted from the ground or via aircraft by pyrotechnic flares and/or liquid fuel generators.  Please visit the FAQ page for more information on seeding concepts and materials.

Is It Effective?

Yes, it can be very successful. Seeding agent and methodologies used in present day operations have been developed and refined over 60 years. Studies have shown certain clouds or stages of cloud development are susceptible to seeding while others are not. Various analysis show that cloud seeding technologies can increase area-wide seasonal precipitation by 5-15% and suppress damaging hail by 25-75% when effectively applied to suitable clouds. Advances in radar data processing and evaluation techniques are helping to provide additional insight into the effectiveness of cloud seeding.

Is it Environmentally Safe?

Published scientific literature clearly shows no environmentally harmful effects arising from cloud seeding with silver iodide (AgI) aerosols have been observed, nor would they be expected to occur. Based on this work, the WMA finds silver iodide is environmentally safe as it is currently being used in the conduct of cloud seeding programs. Click the link below to see the complete WMA Environmental Impact Statement on this topic and for a bibliography of accredited sources.

Current Executive Officers

The Industry's Best Meteorologists, Pilots, Scientists & Researchers
Stephanie Beall

Stephanie Beall


Stephanie Beall is a Meteorologist with North American Weather Consultants in Salt Lake City, Utah. Stephanie has worked as a meteorologist in the field for twelve years, with experience in rain enhancement, hail suppression and snowpack augmentation. She has worked on field projects in Texas, California and Utah. She is a member of the American Meteorological Society and has served on the board of a Local AMS Chapter. She has also served as the Webmaster for the WMA since 2007.

Paul Kucera - WMA Secretary

Paul Kucera


Dr. Paul Kucera has over 25 years of field experience in weather modification assessment and precipitation research. As a Project Scientist at University Corporation for Atmospheric Research, he has led airborne and ground research operations, radar networking, education and outreach, evaluation of experimental forecasts, and assessment of cloud seeding programs for multiple international clients. He currently is Chair of the CGMS International Precipitation Working Group and a member of the American Geophysical Union Committee on Precipitation.

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Frank McDonough


Frank McDonough has been a research and operational meteorologist for the past 25 years. His primary research interests are mountain meteorology, winter storms, and the small-scale structures of subfreezing clouds and precipitation. Frank serves as the program manager for the cloud seeding team at the Desert Research Institute (DRI) and manages research and operational cloud seeding projects in the Rocky Mountains and Sierra Nevada. Prior to working at DRI, while at the National Center for Atmospheric Research (NCAR), he worked on several aircraft icing research programs and co-developed the National Weather Service’s operational in-flight icing products.

Tom Ryan

Tom Ryan


Tom Ryan is a Resource Specialist with the Metropolitan Water District of Southern California in LA. Tom has worked on Colorado River water resources issues at Metropolitan for twenty years and is currently the project manager for the seven Colorado River Basin States' river augmentation programs. For five years Tom served as President of the North American Weather Modification Council.

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