It is extremely unlikely the Madison and Gibbon will be fishable on or near the opener this year. Years with average snowpack they are not ready at that point and given our high and rapidly increasing snowpack so far this winter, the Firehole is likely going to be the only game in town inside the park. If the snowpack keeps climbing (it was 20 points lower in the Madison drainage inside the park less than a month ago), even the Firehole could be questionable depending on how it melts.
Overall we are anticipating our heaviest runoff since 2011 and late summer fishing will be much, much better than early season fishing, unlike the past two years. For comparison, the Yellowstone basin inside the park has 40% more snowpack than it did last year to this point.
I give a full rundown of what we expect for this season on the News Page at www.parksflyshop.com