In just the last week, Montana lost 2 - 8% of its snow water equivalent because of the low rate of snowfall. The dry weather pattern is causing forecasters to predict below average stream flows for 2012. All of this could change, however, if a high-precipitation La Nina weather system begins to take hold. The Missouri River basin is especially in need of such a change, its snowpack level is just 69% of its 30 year average.