What happened
During an approach to the runway, the pilot reported winds of 8 knots shifting from 140 degrees to 210 degrees. Upon touchdown, the aircraft landed on its right tire, at which point the pilot reduced engine power. Before the left tire could make contact with the ground, the aircraft pivoted on the right tire and moved sharply to the left. In an effort to regain directional control, the pilot applied full power. Despite this action, the aircraft slid off the runway and came to a stop facing approximately 180 degrees from its original landing direction.
Findings
A METAR observation at Idaho Falls at 1353 hours reported winds from 190 degrees at 10 knots.