Trout & Water Temps | What to Do When the Rivers Heat Up

Fish Early

If you’re not an early bird, summer trout fishing will make you one. Sunrise to ~10 am is your prime fishing window during the warmer months – when the sun hasn’t yet had a chance to beat down and warm the water to a temperature that’s tough on the fish. 

Bring a Thermometer

Is 10 am a hard stop? Not always. But it’s around the time you should take out your thermometer and check the water. Virtually every fly shop will have them in stock, for this specific reason – if it’s reading 67° or higher, you’ll want to pack it up for the day. 

When the large rivers get too warm, go higher. Generally, the more elevation you gain, the cooler the air and water temperature will be – if you’re fishing the main stem of a river, check out one of its tributaries. High-elevation streams still heat up, but you’re likely to buy yourself another couple of hours of fishing.

If you’re not typically a small stream angler, summer temps offer a great reason to try it out. It’s hard not to love. 

Skip the Grip & Grin

In most trout fishing scenarios, I’m all in favor of a quick grip and grin photo. That said, summertime fishing isn’t one of those scenarios. If you catch a fish that is having a hard time breathing, removing it from the water isn’t going to do it any favors. 

You can still get great shots of your fish in the net or the water as you release it. Experiment with different angles – these photos often come out more interesting than the typical fish-holding hero shot.   

Some rivers and streams will experience closures when water temperatures get too high, but most of the time, it will be on you to recognize the harmful conditions. Always keep a thermometer clipped to your bag, and pack it up before the temperature gets too high. In all likelihood, the trout will still be there the next morning.