How do storms interact with mountains?

We are beginning to find some surprises after a huge research program focused on storms as they slammed into Washington's Olympic mountain range. One of those findings is that snowflakes landing on the Olympic Mountains are larger than they are had they fallen over the ocean.

In the winter of 2015-16, the University of Washington's Department of Atmospheric Sciences and NASA conducted months of testing involving three research aircraft flying out over the mountains and the Pacific Ocean. Called the Olympex project, large amounts of equipment were also used on the ground, from multiple types of rain gauges placed around the Olympic Peninsula to special radar trucks called dopplers on wheels.

The main mission was to validate a new high resolution weather satellite known as the GPM, for Global Precipitation Measurement. The testing is also helping weather researchers better understand how storms interact with terrain, which could provide more accurate forecasts for flooding, landslides, and other hazards.

Papers detailing the findings from the research are expected to roll out over the next five years.