Missouri River April May Fly Fishing Forecast

Missouri River April May Fly Fishing Forecast

Missouri River April May Fly Fishing Forecast

Squeeky attended the annual Upper Missouri River water Advisory Meeting last week and got the skinny on the upcoming water flow predictions and the update on the trout populations. Lots of folks in the room from dam operators, the power company, FWP agents and biologists, TU Conservation, UMOWA officers, lake campground operators, and many more public and private businesses interested in the summer Missouri River flows. About 30 total in the room.

Great presentations this year from 4 or 5 including Stephanie Micek of the DNRC and Jason Mullen of the Great Falls FWP office. That is where most of this information comes from.

Missouri River Trout Populations

Rainbow populations are on the rise. 4816 Rainbows/mile 10″ or better on the upper river. FWP shocks the Wolf Creek to Craig section and the Pelican Point to Cascade reach seasonally. Spring and fall, Three consecutive nights right, center, and left side. The same pools are sampled as to create some consistency.

500 Rainbows/mile in the larger 20″ lengths keep us interested. A nice 4-5 year class is out there. Get some.

Brown Trout seem to be dropping and are now below historic average levels. Some believe that they are on the increase. Simply not true. 269/mile over 10 inches is the current data from Wolf Creek to Craig shocking surveys. The historical average is 563/mile. And about the same on the lower river as well. They are higher in percentage in the Cascade reach.

On the upper reach the rainbow outnumber the brown trout considerably. The brown trout on the upper reach have an age class of approximately 40 Browns/mile 20″-24″. And some of them eat a dry fly. Or a beefy streamer!

Summer Water Flow Projections

The Missouri River drainage area that we draw from is 13,000 square miles. Awesome huh. Last year we finished up at about 80% of average for the water year according to Stephanie Micek of Montana DNRC. This year predicting about a 94% of average water year. That is the prediction so far.

Canyon Ferry is approximately 5′ higher than it was last year. Already. That is encouraging. We can see the movement of water out of Canyon Ferry in anticipation of the water coming format he hills and mountains in our drainage.

Ms. Micek stated that the predicted flows for the Missouri River below Holter Dam will be near the 5,000 cfs mark for the month of April, A probable 6,000 cfs mark for the month of May. And we will wait and see what kind of precipitation will grace us for the month of June outflows into the Missouri River below Holter Dam.

Missouri River April May Fly Fishing Forecast

As you can see on the chart above we may have flows in the 7K range for the month of June. Maximum probable flows over 10K. For flows to exceed that we will have to have above average precipitation starting now.

Which can happen. It did in ’97. In ’98 too. Then not too many years ago in ’08-’11 we had higher than normal flows with a couple of those years approaching 30K cfs. High water for sure. So monitor the rain falling from the sky to understand what kind of water year we will truly have.

The 50 year average for peak water flows comes in at 14, 082 cfs. Will we get there this year?

Missouri River April May Fly Fishing Forecast
Dearborn River Blown out Spring 2015

The snow that is on the ground on April 15th, tax day, is what the water managers base their  model upon. The entirety of the snowfall has already happened. Even if there is a couple of those big spring snows, it really does not effect the outcomes. Unless, it snows and snows and snows. Which can happen.

We have 95% of our historic average snow water equivalent right now. So we hope to roll on through the year at that level. Worst case scenario is 71%. Let’s hope for better than that. I hope we are delivered better than the 80% we saw last year 2016.

Again monitor the precipitation and watch the inflows and outflows. And watch this site. We do not provide occasional information here on this site. We feed you info daily! Honesty and transparency is our model educating you the angler of the info that is important. Not on our schedule, on your schedule. We will pass it on when we hear it!

Missouri River April May Fly Fishing Forecast
The red line is 2017. Go BIG RED


Missouri River Bugs April & May

Midges: Through the  month into May. Not too good this year. But a few around to get your rod out. Fish clusters, individuals, and droppers. You can find the fish rising in pond like areas as well as seam lines. But mostly the soft water insides where the midges are buzzin’ around on the surface.

BWO’s: Mid April into mid June sometimes. But mostly through the end of May. The best and most consistent of the spring bugs. Afternoons are the time when you will see them come off. 2pm and later. They start on the lower river and move uphill. And they have started. So expect more bugs as the month moves on.

Seams, insides, and flats. Sipping trout love this insect. Mayflies are a Missouri River staple. The Blue Winged Olive is one of our favorites. 42F river temp is the start. We are at that now.

Patterns? Cripples, emergers, spinners and duns. Find the rivers best selection at Headhunters in Craig. Not only do we provide the honest info, more than occasionally, we have the best bug selection too. Stop in and see our expert shop staff for friendly bug information including the only free large format map on the river.

March Browns: Mid May. Look for them int he canyon first. A few runs harbor this great bug. A couple weeks on the outside is all we see. So be ready. Mottled winged March Browns are a mayfly that the fish go nuts over. Most keep this one under their hat. Specific patterns available at HH will help you fish with confidence. An Adams will get it done if needed.

Mother’s Day Caddis: Early to Mid May. Sometimes later. Mid Canon and below. X Caddis is all you need. A film fly is not a bad idea either. Big Brown Trout get amped up man. This is a great one and short lived too.

Missouri River April and May Weather

Variable. That is the definitive answer. As many, most, if not all of you know that you should come the Mo with your best spring arsenal. Rain jackets, snow clothing, gloves, neck protection, hand warmers, Thermos’, sunscreen, sun hats, multiple layers…whatever you can stuff in your pack or luggage!

Averages above. We van have rain, snow, sleet, wintry mix, wind, and sun too. Obviously the warmer weather warms the water. The cold ass weather cools it rapidly too. It takes far longer to increase water temps than it does to cool it off.

So come prepared for battle fishing here in Craig Montana. I know I have been ill prepared a few days already this spring. It takes a beating to remind me that summer is not here, and winter is not over.

This las week we have had 70F and windy sun all the way to 3″ of snow and sleet on the river. That is a wide range!

Missouri River April May Fly Fishing Forecast

And there you have it. Our current and future situation here on Montana’s Missouri River. A comprehensive look at the months ahead. We love spring here in downtown Craig. It brings life to us after a damn cold winter. Friends, anglers, smiles, laughter, and the smell of trout…whitefish too!

Give us a call at the shop on our Trout Hotline 730am til 8pm daily for more info if this does cover enough information. And it may not. We love to talk about trout here at Headhunters Fly Shop. 406-235-3447

Headhunters is your source for entertainment, information, education and customer service on this one of a kind trout fishing resource.

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  • Mark- Thanks for the informative post! Always appreciate the effort that goes into compiling and presenting your updates.

  • Herbie Gross
    April 11, 2017 9:36 am

    Mark great comprehensive post, as always thanks, for the good work and keeping us all up to date.

  • How many rainbows, of what size, and from what stretches do you recommend keeping?

  • Interesting, I don’t see my prior comment. How many rainbows, of what size, and from what stretches would you recommend keeping? Or is it your position that every fish should be released?

  • Braden Lewis
    April 12, 2017 2:14 pm

    Mark, we advocate catch and release angling. If you intend to keep fish, we recommend keeping rainbows instead of browns. You are allowed to keep up to three fish per day. Only one of them can be a brown trout and only one of them can be over 18″. However we suggest releasing all browns and any fish over 18″. Many anglers think that fish harvested from Holter Lake this time of year taste better than fish from the river. Many of the lake fish are stocked, while the river fish are wild, so we aren’t as protective of the lake fish. You are allowed to keep up to 5 rainbows from the lake. All brown trout caught in the lake must be released. Mark, we are obviously protective of the Missouri River resource, but we understand that not all anglers practice catch and release. It sounds like you are interested in harvesting fish responsibly, so thank you for that.

  • Nice explanation, Braden. Hope that Mark, from above, comes to fish the Mo’ because everyone who loves fishing should fish here at least once. I hope he hires an HH guide so he does well because regardless of what he may have heard, the truth is the Mo’ ain’t easy.
    And Mark should know also that, again, regardless of what he may have read or heard, those of us in Montana who release the fish we catch are in fact a small minority. In over sixty years of trout fishing in Montana, I can think of only a handful of fishermen who keep their catch that stop when they’ve filled the limit. Ours is a “hell, one more fish can’t hurt anything ” society. Bet the FWP will back me up on that too.
    There is one more reason not to eat fish from the Missouri that I could point out, Mark. Fish from rivers whose source headwaters are located in the geothermal regions of Yellowstone Park contain measurable amounts of mercury, arsenic and lead. Not hazardous amounts but amounts large enough to be considered more than just trace amounts. And your body never cleanses itself of these heavy metals. Pretty sure that eating a fish or two won’t hurt anyone one, but the FWP was concerned enough that there is a section in their website naming some fifty or so waters of concern listed and consumption recommendations noted. Look it up it’s there. Not trying to scare you into catch and release- just making you aware.

  • Thanks Braden, I catch and release most of the time, but do think we can assist the habitat and be conservationists by appropriately keeping fish in some situations. For example, I often keep lots of brookies in waters that have native cutties. I think catch and release is a great thing and why we can have great wild fisheries, but I’m concerned that it has become such a mantra among some that they forget keeping some fish can be a management tool. Contrary to what Russ says, I strongly disagree that those who catch and release are a small minority, especially if you are just looking at rivers. Is the Mo’ at or near carrying capacity such that some mid-range rainbows should be kept? Would that help the declining brown trout population? I don’t know, that’s why I ask. For now, I’ll continue not keeping fish from Holter dam down, but I encourage Russ to consider that there can be options between the polars of keep everything and release everything.

  • Mark, let me say first that I in no way implied that I subscribe to an absolute catch and release philosophy. To the contrary, I’m pretty sure that since the 1950s I’ve eaten enough trout to feed a small Asian country (slight exaduration here) and I still enjoy them. I tend to be wordy, as old men can be, so maybe you misunderstood while wading through my comment.
    I fish a lot on the Mo’ and throughout each year I end up taking a fish home. Some just won’t revive, whether they’ve been played too long, suffer from previous (or my own) mishandling or have become too injured in an accidental manner during landing or playing. It happens. I also hold no ill will towards those who fish to eat fish as long as they follow limit designations or creel limits. FWP, with budget limitations, can’t supply enough people to monitor every angler, every fishery or even a tiny percentage of either so there is no viable way for biologists to even guess as to the number of fish taken almost anywhere. My point is that, while I don’t feel that people are inherently bad, even Sigmund Freud said that the majority of our species is only as honest as they have to be.
    One more point. Having spent many years in sales of fishing equipment in small fly shops, national sporting goods stores and once in a large national “box store “, in Montana, and from studying statistical literature supplied to me and from personal experience, if you consider only rod and reel sales, area consumers in the Great Falls-Helena region buy more spinning/bait rigs than fly rigs at a rate of almost 20 to 1. And one retail sales mag study I read said that most fishing purchases are put to use within 50 miles from purchacepoint. This is why I say that catch and release fly fishermen are in the minority, even on the Mo’. Years of statistics, not my opinion, say this is true. Sorry for any misunderstanding.

  • WOW, this is insanely informative! I too, have hopped on the fly fishing train and I am SO glad I did. Thanks for sharing. Once you start with fly fishing, it’s impossible to stop =)!

    Great post! You killed it! And I’m so glad you are finally on board with fly fishing- yay!

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