Chris Izworski’s daily Michigan trout report turns to the AuSable this morning, and the honest assessment is this: the river is running hard, well above its historical April average, and the fishing window is narrow. Before you load the truck for the drive northeast, understand what the numbers are telling you.
The USGS gauge at the AuSable is holding at 2040 cubic feet per second. For a late April day, that’s running at 153 percent of the 30-year median for this date. The 75th percentile—the level you’d expect on a high-flow day—sits at 1680 cfs. You’re above that now, and the water temperature is a cold 52.2 degrees. The gauge height of 4.5 feet means the banks are wider, the current faster, and the holding water for large fish has shifted from its usual lies into the deeper pools and behind substantial structure.
The Michigan Trout Report rates conditions as Fair. That means fishable, with qualification: pick your spots. This is not a day to cover water aggressively or to expect the river to forgive poor presentation. Browns and rainbows are still accustomed to winter habits—they’re not yet distributed across the shallows and flats where you’d find them in May and June. High water compresses them.
What the Weather Tells You
Today looks pleasant enough. Mostly sunny, 75 degrees, minimal wind. The evening could be excellent: sunset at 8:30 pm, with a genuine golden-hour window from 7:00 to 8:30 where light conditions favor dry-fly rises. That matters for what comes next.
The forecast shows a 75 percent chance of rain in the next 48 hours. Friday carries a 64 percent rain probability with a high of only 64 degrees. Saturday drops further: 56 degrees, 50 percent rain chance. When you layer a 75 percent chance of precipitation onto a river already running at 153 percent of median flow, the outcome is clear. The AuSable will rise. Possibly significantly. The window for decent wading closes, not tomorrow, but soon.
Sunday is the break. Four percent rain chance, with a high near 63 degrees. If you’re flexible with your schedule and genuinely interested in the AuSable right now, that’s the day to mark. The water will be dropping by then, moving back toward something manageable.
The Hatch Picture
April on the AuSable means the Hendricksons are coming. You’re not quite there yet—the real emergence typically peaks in early May—but the precursors are live now. Midges and small Blue-Winged Olives are hatching sporadically in the afternoons. Early Brown Stoneflies and Grannom Caddis are active, particularly in the faster water where nymphs are drifting or where adults skitter on the surface.
On a day like today, with decent light and a decent evening window, the play is nymphing the riffles with a Hare’s Ear or Early Brown Stonefly pattern in the #12 range, then switching to dries in the last hour if a rise forms. The cold water and high flow mean fish are feeding, but they’re not doing it with the abandon you’ll see in three weeks. Every presentation matters.
If the afternoon clouds up and you’re fishing the slower water near Grayling or Burton’s Landing, small emergers—RS2 or Sparkle Dun in #18—fished just subsurface on long fluorocarbon tippet will catch fish. The special regulations water on the Holy Water stretch demands flies-only, and the pristine spring-fed currents there hold the river’s best browns. That water will fish better today than the main stem, partly because the springs moderate temperature and flow variation.
The Wading Reality
High water and cold temperature demand respect. The current is pushy. Wade deliberately. Know where your exits are. The AuSable has excellent public access at Grayling, Mio, Burton’s Landing, and Wakeley Bridge, but access means nothing if you’re overcommitted in a channel that’s running faster than you anticipated. Fish the edges, the slack water, the inside bends. Let the faster current run.
What to Do
If you’re committed to the AuSable today, fish the evening. The golden hour from 7:00 to 8:30 pm offers your best chance at dry-fly rises, and the cooler light of late day can trigger feeding in high water. Bring small flies and long, fine tippet. Expect to work for every fish.
If you have flexibility in your schedule, wait for Sunday. The rain will clear, the flow will decline, and the water will be fishable in a more conventional sense. One day of patience can mean the difference between an afternoon of frustration and a day that reminds you why the AuSable is considered one of the premier wild trout fisheries in the Midwest.
For real-time gauge data and flow updates, check https://trout.chrisizworski.com.