The Riffle Blog
Technique, river intel, seasonal strategy, and the science behind the hatch.
Understanding CFS: What River Flow Actually Means for Fishing
CFS is the most-checked number in fly fishing. Here's what it measures, why raw numbers are misleading, and how flow changes where fish hold and what they eat.
The Brown Drake Is Running Hot
Silver Creek has banked 2x the normal GDD by April. We're tracking our emergence prediction in real time — updated weekly until the drakes hatch.
How Fast Do Rivers Recover After a Blowout?
We analyzed 1,319 blowout events across 144 rivers using 10 years of USGS discharge data. The median river is fishable again in 7 days.
When Do Hatches Really Start?
We ran 20,000 data points through a GDD model for 11 western rivers. The hatch charts are wrong by an average of 50 days.
The Hatches Are Moving
Western hatches are shifting earlier. GBIF occurrence records back up what anglers have felt for years — here's what the data shows.
Reading Water Temperature Like a Guide
Water temperature is the single most important variable in fly fishing. Here's how to interpret it beyond the raw number.
Spring Runoff Strategy: When to Fish and When to Wait
Runoff doesn't mean unfishable. How to read flows, pick your windows, and find fish when rivers are high.
The Madison River: A Data-Driven Guide
Flow patterns, hatch windows, and what USGS data tells us about Montana's most famous trout stream.