May 2021 Montana Fly Fishing Forecast
By angelamontana

Posted: May 6, 2021

Montana Angling Co posted the following flyfishing forecast for May:

May is right around the corner and with it our anglers and guides will kick-off the prime Montana fly fishing season. As water temps climb out of winter lows, some of the first great hatches of the year will arrive on our Montana rivers. Great hatches mean great dry fly fishing.

The mother’s day caddis hatch on the Madison River, Yellowstone River, and Missouri River is usually the star of the show early-mid May. This hatch gives a whole new meaning to the term “blanket hatch” with mats of caddis piling up in every river eddy and trout rising to take them. Mixed in on overcast days anglers will also find hatches of Blue Winged Olive (BWO) mayflies continue on through the middle of the month. Anglers with a keen eye will also find March Brown mayflies, skwala stoneflies, and even a few early season terrestrials mixed in as water flows come up.

Spring run-off on our area freestone rivers has held off for now but with day time highs in the 70s it is a matter of days before the Yellowstone River, Gallatin River, Jefferson River, and other area freestone rivers run high and muddy. With that anglers in Bozeman, MT will find the best fly fishing on the Lower Madison River, Upper-most Madison River, Paradise Valley Spring Creeks, and private water lakes through late-June. Yellowstone National Park opens for fly fishing the Saturday of Memorial day weekend and is a great option for wade fishing later in the month of the Firehole and Gibbon Rivers.

Anglers fly fishing on the Missouri River near Craig, MT will be treated to some of the best fly fishing of the year through the month of May. The Missouri River tailwater is not affected by spring-run off due to snowmelt and projected flows below average for 2021 should make for excellent dry fly fishing. The nymphing on the Missouri River is always some of the most productive of the year with high catch rates and the largest average sized trout of any river in Montana. We are also hopeful that lower flows could make for some of the best streamer fishing in recent history.