The Snotel site indicates 46 inches of snow water at Trinity. The chart above shows about 50 years of data on the amount of snow pack at the end of May at this site, correlated with average water flows in June in the South Fork Boise at Featherville.  Trinity snow pack is not a perfect predictor, but the correlation values are respectable.  The 46 inches is the red data point, and as shown the average flow for June projects to be around 2,600 cfs, assuming the regression line is an accurate estimate for this year. Last year’s snow pack/flow data point  is green. The past five days the flows have been 3,500 cfs. Flows have probably peaked in the past few days and should begin to drop through the month, but flows will most likely easily exceed 2008 flows through June.  All the snow that still has to melt will have to pass through the reservoir since it’s full.

Conclusion: Think you’ll be wading soon?  Forget it.  How about those “normal” flows of 1,600 cfs or 1,800 cfs?  Probably not.  Best to expect flows in the South Fork Boise below Anderson Dame to remain above 2,000 cfs for the rest of the month.  Based on updated data we will see flow settle in the coming days in the range of 2,000 cfs.  The above chart was based on snowpack but not water equivalent inches and there is less water than at first thought.  See updated chart above that shows snow water trends at Trinity Mtn.