Cold weather over the past few days has dropped the Yellowstone and Boulder Rivers into marginally fishable shape. They would have gone lower, but the cooldown was accompanied by a VAST amount of snow and rain yesterday and today, so things are still pretty marginal.
As of right now, the Yellowstone is flowing at 7350cfs at Gardiner and 9870cfs in Livingston. “Safe” float levels are 10,000 in Gardiner and 12,000 at Livingston, with the float stretches that are safe limited to flatter sections without aggressive eddies, such as the Cinnabar to Yankee Jim, Carbella to Point of Rocks, or Emigrant to Mallard’s Rest sections. The Boulder is down to 1560cfs, with 2000 safe. I’m not sure if the large tree which forms a dangerous and almost impassable barrier on the Boulder at Spring Creek Campground south of Big Timber is still there or not.
At the above flows, streamers pounded on the bank on sink-tips, using 1X or heavier tippet, is your best bet. You may also move some fish on stonefly and large attractor nymphs drifted through bankside pockets, but you’ll lose a lot of flies doing this.
Neither river is low enough for more than very difficult wade-fishing. On the Yellowstone, concentrate on the steep, rocky banks through and just past the town of Gardiner, fishing the slow holes next to the banks.
Here’s the flow data for the Yellowstone River at Corwin Springs, near Gardiner:
Here’s the streamflow predictions for the river at Livingston. Predictions are not provided for the Corwin Springs graph. Subtract about 2000cfs from the Livingston graph to get an approximation of expected flows at Corwin.
That big spike Tuesday afternoon will definitely be “all she wrote” for the runoff break fishing. Temperatures in Livingston are forecast to rise into the high 80s by next weekend, and that will send the remaining snow GUSHING down. Expect rivers to begin dropping again about 3 weeks after they shoot up.