Sometime around mid-June, something shifts on the Provo. It happens quietly at first — a few large olive-bodied mayflies wobbling off the surface, an unhurried rise somewhere near the far bank. Then more. Then the fish that have been sipping midges and PMDs all spring suddenly commit. Fully, visibly, aggressively. The Green Drake hatch has started, and for the next two to three weeks, the Provo will fish as well as it ever does. The Green Drake — Drunella grandis — is not a subtle insect. At a size 10 or 12, it is enormous by mayfly standards. A T-bone steak, as one longtime Provo guide put it, compared to the midges these fish have been eating all winter. When the hatch aligns, brown trout that have been almost impossible to coax to the surface will suddenly eat big dries with the kind of confidence that makes your hands shake a little. This is the week most local anglers have been waiting for since February. Right now, in mid-June, the Provo is in peak overlap — Green Drakes and PMDs hatching simultaneously, fish stacked in feeding lanes from late morning into early afternoon. The window is narrow but extremely productive. If you know how to read it. Understand the window The hatch runs from roughly 10 a.m. to 1:30 p.m. This is not a suggestion — it is almost a clock. Air temperatures this time of year push into the mid-to-upper 80s by afternoon, and once water temps climb too high, the fish drop off the surface and the hatch shuts down. Get on the water by 7 a.m. to work the morning midge activity, position yourself in productive water before 10, and plan to be off by early afternoon. Fighting the heat on the Provo in the middle of a June afternoon is not the move, for the fish or for you. If you can get back out after 5 p.m., do it. As temperatures drop, a caddis hatch takes over and the visual fishing picks back up — skating a CDC Caddis through riffles in the evening is some of the most fun dry fly fishing you'll have all season. Flies & Approach Pre-hatch nymphing (7–10 a.m.)
Before the dries start working, fish the nymph. Green Drake nymphs start as brown, then turn nearly black just before emergence — look for the whitish split in the wing case, which signals they are about to pop. Fish a size 12 Green Drake nymph deep in feeding lanes. A Pheasant Tail or Hare's Ear in sizes 12–14 also works well in this window. This is often when the biggest fish of the day eat. Dry fly window (10 a.m. – 1:30 p.m.)
Switch to a size 10–12 Green Drake Comparadun or Paradrake when you start seeing consistent rises. The Comparadun is a better choice on flat, technical water — lower profile, more accurate silhouette. The Paradrake sits higher and is easier to track in broken water. If fish are rising but ignoring your dry, drop a Green Drake emerger off the bend of the hook — the fish are often eating the bug before it fully escapes the shuck, not the adult on top. PMD overlap
When both hatches are going simultaneously, watch where individual fish are feeding before you cast. A fish sipping steadily in a slow eddy is probably keyed on PMDs. A fish eating aggressively in a faster lane is more likely eating Drakes. Match accordingly — don't assume every rising fish wants the big fly just because you do. Evening caddis (after 5 p.m.)
CDC Caddis, olive or tan, size 16–20. Skate it through riffles with a slight downstream swing. The takes are violent and the fishing is fast. Worth staying for. What the hatch actually looks like The Green Drake is an awkward bug. It emerges slowly, struggling to pull free of its shuck, sitting on the surface longer than most mayflies before it gets airborne. That extended drift time is exactly why trout eat it so readily — there is no urgency required. The fish have time to inspect and commit. Which also means they have time to inspect and refuse, especially on the Provo, where fish have seen more flies than most anglers care to admit. Drag is the enemy. A dead drift that skips or drags even slightly in moving current will get ignored by fish that are otherwise eating greedily. This is a river that punishes sloppy presentation. Reach casts, slack-line mends, and short accurate drifts will always outperform distance. The Provo rewards precision, not boldness. One more thing worth knowing: the hatch does not fire every day with equal intensity. Weather matters enormously. Overcast days with mild temperatures often produce the best hatches — heavy cloud cover seems to slow the bug's emergence, keeping more insects on the surface longer and concentrating fish in feeding lanes. On bluebird days with rising heat, the hatch can be shorter and spottier. Watch the forecast and adjust your expectations accordingly. The Green Drake hatch on the Provo is fleeting — two, maybe three weeks if the conditions cooperate, and then it is over until next year. The fish that were rising with abandon in the afternoon feeding lanes go back to being selective and difficult and entirely indifferent to your confidence. But for this small window in mid-to-late June, the river offers something genuinely rare: big trout, big flies, and visible takes in bright daylight. That combination does not exist everywhere. The anglers who have fished the Provo long enough know to rearrange their schedules around it. If you have not been on the water yet this week, go soon. The clock is running.