.png?width=300&height=100&name=Rise%20Beyond%20Logo%2010.29.24%20300x100px%20(2).png "Rise Beyond Fly Fishing Co. logo featuring a cowboy riding a large trout, holding a fishing rod in one hand and a camera in the other, with stylized text in a rugged, outdoor-themed font")
.png)
If you're fly fishing Colorado’s Front Range in May, you’re in the middle of some of the best spring hatches of the year. While runoff season complicates flows and clarity, tailwaters and select stretches of freestones are still fishing well—especially if you’re matching the hatch.
This May hatch chart covers core rivers along the Front Range, including the South Platte (Deckers & Cheesman), Clear Creek, Bear Creek, Boulder Creek, Big Thompson, and the Arkansas near Salida.
Let’s break down what’s hatching, when to fish it, and the best fly patterns to match.
Listen to the Podcast!
May Hatch Chart – Colorado Front Range Rivers
| River | Hatch | Peak Time | Size Range | Suggested Patterns |
|---|---|---|---|---|
| South Platte (Deckers) | Midges, BWOs, Caddis | 10am–2pm | 18–24 | RS2, Zebra Midge, Graphic Caddis |
| Cheesman Canyon | BWOs, Midges, Micro Stones | 11am–3pm | 18–22 | Barr’s Emerger, Top Secret Midge |
| Bear Creek | Caddis, Midges, BWO | 1pm–5pm | 16–20 | Elk Hair Caddis, Parachute Adams |
| Clear Creek | Caddis, Golden Stones | 2pm–6pm | 12–16 | Yellow Stimulator, Beadhead Prince |
| Boulder Creek | Caddis, BWOs, Midges | 11am–4pm | 16–20 | CDC Caddis, Pheasant Tail |
| Big Thompson | Midges, BWOs, Caddis | 10am–3pm | 18–22 | Griffith’s Gnat, RS2, Soft Hackles |
| Arkansas River (Salida) | Caddis, Baetis | 12pm–6pm | 14–18 | LaFontaine Caddis, Pats Rubberlegs |
Front Range May Hatch Overview
Midges
Active all day, especially in tailwaters like Deckers, Cheesman, and Big Thompson. Tiny and prolific, they’re your go-to when nothing else is popping.
Blue Winged Olives (BWOs)
Still dominant on overcast or drizzly days. Expect them to taper off later in the month but still produce good dry fly windows.
Caddis
This is the main event in May. From Bear Creek to the Arkansas, Caddis hatches explode on warmer days. Focus on pupae patterns in the morning, and dry flies in the afternoon.
Stoneflies
Golden stoneflies and micro stones are present, especially on Clear Creek and some foothill freestones. Use attractor dries or nymphs with rubber legs.
Best Flies for Front Range Rivers in May
OVERALL
- RS2 (black, gray, olive, #20–22)
- Top Secret Midge (#22–24)
- Zebra Midge (#20–24)
- Barr’s Emerger (#18–22)
- Elk Hair Caddis (#14–18)
- Yellow Stimulator (#12–14)
- CDC Caddis (#16–18)
- LaFontaine Sparkle Pupa (#14–16)
- Beadhead Prince Nymph (#14–18)
- Soft Hackle Caddis (#16)
South Platte River (Deckers)
- RS2 (#20–22)
- Zebra Midge (#22–24)
- Top Secret Midge (#22–24)
- Barr’s Emerger (#18–22)
- Sparkle Wing RS2
- WD-40 Midge (#20–24)
- Flashback Pheasant Tail (#18)
- Graphic Caddis (#16)
Cheesman Canyon
- RS2 (#20–22)
- Top Secret Midge (#22–24)
- Barr’s Emerger (#20)
- Miracle Nymph (#20)
- JuJu Baetis (#18–20)
- Black Beauty (#22–24)
- CDC BWO Emerger (#20)
- Mole Fly (#20–22)
Bear Creek
- Elk Hair Caddis (#14–18)
- Parachute Adams (#16–20)
- CDC Caddis (#16)
- Beadhead Prince Nymph (#16)
- Soft Hackle Hare’s Ear (#16)
- Pheasant Tail (#18)
- Black Copper John (#18)
- Griffith’s Gnat (#20)
Clear Creek
- Yellow Stimulator (#12–14)
- Beadhead Prince Nymph (#14–16)
- Pats Rubber Legs (#10)
- Elk Hair Caddis (#16)
- Flashback Hare’s Ear (#14)
- Gold Ribbed Hare’s Ear (#16)
- Iron Sally (#14)
- Soft Hackle Pheasant Tail (#16)
Boulder Creek
- CDC Caddis (#16)
- Parachute Adams (#18)
- RS2 (#20)
- Beadhead Pheasant Tail (#18)
- JuJu Baetis (#18)
- Zebra Midge (#22)
- Elk Hair Caddis (#16)
- LaFontaine Caddis Pupa (#16)
Big Thompson River
- Griffith’s Gnat (#20)
- RS2 (#22)
- Black Beauty (#22)
- Barr’s Emerger (#20)
- CDC BWO Dun (#20)
- Zebra Midge (#22)
- Bubble Back Emerger (#20)
- Micro Mayfly (#18)
Arkansas River (Salida Area)
- LaFontaine Caddis (#14)
- Pats Rubber Legs (#10)
- Graphic Caddis (#16)
- Beadhead Prince Nymph (#14–16)
- Soft Hackle Caddis (#14)
- Flashback Pheasant Tail (#16)
- Barr’s BWO Emerger (#18)
- Tan Elk Hair Caddis (#16)
Tips for Fishing May Hatches on the Front Range
- Start deep: In the morning, focus on nymphing with caddis pupae, baetis, or midge patterns.
- Watch for surface eats: Cloud cover often triggers BWO dry fly windows mid-morning.
- Caddis love sun: When the sun warms the water, expect explosive afternoon caddis activity.
- Adjust tippet: Use 5X–6X for BWOs and midges; bump to 4X for larger caddis and stoneflies.
- Use movement: Twitch caddis dries or swing soft hackles in the afternoons.
FAQ: Front Range Fly Fishing Hatches in May
What flies are best for Colorado rivers in May?
The best flies for May hatches in Colorado include RS2s, Elk Hair Caddis, Zebra Midges, Yellow Stimulators, and Sparkle Pupae. Match size and color to your local hatch.
When do caddis start hatching in Colorado?
Caddis typically begin hatching in late April but peak in May, especially on warm afternoons. They are most prolific on freestone rivers and creeks.
Where should I fly fish near Denver in May?
Top picks include Bear Creek, Clear Creek, Deckers on the South Platte, and Waterton Canyon. All offer spring hatches and fishable conditions—even during early runoff.
Do hatches still happen during runoff?
Yes—especially on tailwaters and higher elevation freestones. Even when flows are high, you can often find slower water near the bank with active hatches.
Is May a good month to fly fish in Colorado?
Yes. May offers strong hatches, hungry post-winter trout, and excellent caddis activity. You’ll need to adjust for flow and clarity, but the fishing can be excellent.
Final Take: Why May Is One of the Best Months to Fish the Front Range
May fly fishing in Colorado’s Front Range is all about hitting the hatch windows between snowmelt pulses. With midges still strong, BWOs lingering, and caddis in full swing, there’s no shortage of insect activity.
The key is timing. Hit tailwaters in the morning for midges and BWOs, then move to freestones in the afternoon for the caddis rush.
Use the hatch chart above, pick your stretch, and bring a mix of nymphs, emergers, and dries. May might be messy, but it’s loaded with opportunity.
