S8, Ep 42: Exploring Terrestrials and Summer Patterns: George Costa's Fishing Forecast
Episode Overview
In this Central PA Fishing Report from The Articulate Fly, host Marvin Cash checks in with George Costa, manager at TCO Fly Shop in State College, Pennsylvania, for a timely early-summer conditions and hatch update. The season is at a pivotal transition: the dominant spring hatches are winding down, the summer hatch calendar is coming online and terrestrial season is officially starting — all critical intelligence for anglers planning Central PA trout outings over the weeks ahead.
Costa delivers a full-picture conditions read. Water levels are running a touch below seasonal average, with recent rain bringing some temporary color and a slight rise. Temperatures have been stable but are beginning to creep into the mid-60s°F on brighter, hotter days, which makes temperature-checking a new essential habit for summer outing planning. The hatch situation is in transition: sulphurs are still producing but require evening commitment on sunny days, while Cahills, Isos, summer quills, caddis, size 16 Cornutas and scattered stoneflies fill out the summer hatch calendar. Cloudier days give anglers an earlier dry fly window, while bright days push the best action to last light. On the nymph front, the prescription shifts to smaller, more precise patterns — perdigons and small Walt's worms — as larger attractor-nymph approaches give way to a tighter subsurface game. Crucially, Costa signals that the greenie weenie hatch (inchworm fall) is officially underway, making this the moment to add inch worms, ants and beetles to the summer dry fly box. Shop news includes a topwater smallmouth tying class with Caleb Rebarchak at the State College location, the All Fins In tournament benefiting Clearwater Conservancy and a fly fishing festival at TCO's Boiling Springs shop in August.
Key Takeaways
- Why the greenie weenie (inchworm fall) marks the start of terrestrial season in Central PA and why inch worms, ants and beetles should be in your box from here forward.
- How to shift your nymph game as the major spring hatches wrap up — smaller, more precise patterns like perdigons and Walt's worms become the go-to subsurface approach.
- When to start actively monitoring water temperatures as summer heats up, particularly on bright, sunny days when temps begin pushing into the mid-60s°F range.
- Why evenings are your best window for dry fly fishing on Central PA trout water as summer sets in, with cloudier days pushing hatch activity earlier in the day.
- How to approach the variable nature of summer hatches in Central PA, where a strong emergence one evening can be followed by minimal activity the next — making patience and water-reading essential.
Techniques & Gear Covered
The episode centers on the tactical adjustments required as Central PA enters its early-summer transition. With the major spring hatches largely behind them, George Costa recommends downsizing nymph presentations to smaller, more precise patterns — specifically perdigons and small Walt's worms — as fish dial in to the subtler subsurface fare that characterizes this period. On the dry fly front, the priority shifts to evening sessions targeting sulphurs, Cahills and Isos, with summer quills, caddis, size 16 Cornutas and scattered stoneflies filling out the hatch calendar for those willing to stay on the water late. Terrestrials take center stage starting now, with Costa specifically calling out the greenie weenie as the signal that the inchworm fall has begun, while also recommending ants and beetles as essential additions to the summer dry fly box as conditions warm into the heart of the terrestrial season.
Locations & Species
Central PA's limestone stream corridor around State College is the setting for this report, with TCO Fly Shop's State College location serving as the operational center for George Costa's conditions read. While no specific stream names are mentioned in this episode, the conditions, hatches and tactical advice apply broadly to the region's wild trout fisheries — the spring creeks and limestone runs that draw anglers from across the mid-Atlantic for their hatch diversity and technical dry fly fishing. The key seasonal context is the early-summer transition: water temperatures are beginning to creep toward the mid-60s°F on warmer days, which will become an increasingly important factor for trout welfare and fishing strategy as summer advances.
FAQ / Key Questions Answered
What hatches are active in Central PA as summer gets underway?
The major spring hatches are mostly wrapping up, but the calendar remains active. Sulphurs are still coming off in the evenings, with Cahills, Isos, caddis, summer quills, size 16 Cornutas and scattered stoneflies all in play as summer takes hold. George Costa notes that hatch activity can vary significantly day to day at this time of year — a strong emergence one evening can be followed by minimal activity the next — so working the water methodically and being in the right place at the right time is the primary strategy.
When is the best time to fish dry flies on Central PA trout water in early summer?
Evenings are the priority window for dry fly action during this period. On sunny or hot days, Costa advises anglers to stay late to catch the best hatch activity, particularly for sulphurs. Cloudier days push bug activity earlier in the day, giving anglers a longer productive window — so overcast conditions are worth capitalizing on when they arise.
What nymph patterns work best as the big hatches wind down in Central PA?
When the major hatches wrap up, Costa recommends shifting to smaller, more precise nymph patterns rather than larger attractor approaches. Perdigons and small Walt's worms are his go-to subsurface options for this period, matching the smaller aquatic fare that fish are keying on once the spring hatch season gives way to summer conditions.
When does terrestrial season start in Central PA and what flies should I have ready?
Costa signals that the greenie weenie hatch — the inchworm fall that marks the beginning of terrestrial season in Central PA — is underway now. Anglers should have greenie weenies in the box along with ants and beetles, and can expect those patterns to become increasingly productive as the warmer months set in. Costa frames this as one of the more reliable transitions of the summer season: once the greenie weenies start dropping, terrestrials will carry the dry fly game through the heat of summer.
Related Content
S8, Ep 35: From Sulphurs to Drakes: George Costa's Essential Fishing Report for Central PA
S8, Ep 30: Central PA Chronicles: George Costa's Guide to Spring Fishing Conditions and Techniques
S7, Ep 57: Cicada Mania: Central PA Fishing Insights with George Costa
S7, Ep 70: The Dog Days of Summer: Trico Tactics in Central PA with George Costa
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In this Central PA Fishing Report on The Articulate Fly, host Marvin Cash checks in with George Costa of TCO Fly Shop in State College for an early-summer conditions update on Pennsylvania's limestone trout streams. With the bigger spring hatches mostly wrapped up, George walks through what's still coming off — sulphurs in the evenings, cahills, Isonychia, summer olives, summer quills and caddis — while flagging the arrival of terrestrial season as greenie weenies, ants and beetles begin to take over as the primary producers. Evening fishing windows are now the priority for dry fly anglers, while nymphing with perdigons and small Walt's worms remains productive throughout the day. George also covers upcoming events at TCO Fly Shop, including a smallmouth fly tying class with Caleb Rebarchak focused on topwater patterns, the All Fins In bass tournament benefiting Clearwater Conservancy and a fly fishing festival at the Boiling Springs location in August.
EPISODE SUMMARY
Guest: George Costa - Shop Manager at TCO Fly Shop (State College, Pennsylvania)
In this episode: Shop Manager George Costa shares an early-summer conditions update for Central Pennsylvania trout streams, covering the tail end of spring hatches and the start of terrestrial season. Topics include current hatch activity (sulphurs, cahills, Isonychia, summer olives, summer quills, caddis), nymphing strategies for the transition period, evening dry fly timing and what anglers should expect as warmer months arrive.
Key fishing techniques covered:
- Evening dry fly fishing during summer hatch windows (sulphurs, cahills, summer olives, caddis)
- Nymphing with perdigons and small Walt's worms
- Terrestrial presentations with greenie weenies, ants and beetles to open the summer season
- Reading cloud cover vs. sunny day timing to find earlier or later hatch activity
- Water temperature monitoring on warm, bright days as mid-60s readings become possible
Location focus: Central Pennsylvania trout streams; Centre County limestone water including the Spring Creek and Penns Creek watershed
Target species: Wild trout (primarily brown trout)
Equipment discussed: Perdigon nymphs, Walt's worms, greenie weenie patterns, ant and beetle terrestrials, sulphur patterns, Cahill patterns, Isonychia patterns
Key questions answered:
- What hatches are active on Central PA limestone streams in early summer?
- When is the best time to fish dry flies during the summer months in Pennsylvania?
- What terrestrial patterns should trout anglers start fishing as spring hatches wind down?
- How do water temperature and cloud cover affect hatch timing in summer?
Best for: Trout anglers planning trips to Central Pennsylvania limestone streams during the early-summer transition from spring hatches to terrestrial season
FULL TRANSCRIPT:
Marvin Cash
Hey folks, it's Marvin Cash, the host of The Articulate Fly. We're back with another Central PA Fishing Report with the man himself, George Costa. George, how are you?
George Costa
I am amazing as always, Marvin. Always, always, always.
Marvin Cash
Ah, yes. And we, we had to skip a week because you were tarpon fishing.
George Costa
I was indeed. Tarpon fishing. Not really tarpon catching, but tarpon fishing. It got a nice little trip in there last week. So that was, that was a lot of fun.It was nice to see and do different things.
Marvin Cash
Yeah. Before the heat down there gets brutal. I that I enjoyed meeting and seeing people at icast but do July in Orlando is pretty miserable.
George Costa
Yeah, I'm sure. Man, it gets swampy down there. It is, it is in fact an entire swamp.
Marvin Cash
Yeah.So, you know, looked at your weather, you're probably seasonal right now on temperatures, but you're going to get some rain and kind of cool off maybe over the next week to 10 days. What are you seeing on the water?
George Costa
On the water it's been pretty good. Even conditions levels are seasonal. A touch below. A little bit more rain wouldn't be bad. We've got some more storms maybe coming through tonight.We had a little bit of rain yesterday, so everything kind of came up. Had a little bit of color from last night, but not too bad on the water. So conditions have been good. Temps have been pretty stable so far.Haven't really had to worry yet about warmer temps. A couple warmer days.It was getting up into like mid-60s, but you know, definitely time of year to start checking your temps, especially on those brighter sunny or hot days. Hatches have been pretty typical for this time of year. Most of our bigger hatches are kind of wrapping up.There's still some sulphurs around in the evening. You gotta really stay late for those best dry fly hatches. Cloudier days, you'll see bugs a little earlier, but we've got some cahills coming off.We've got ISOs here and there, a couple stoneflies around. You know, most, like I said, most of the bigger hatches are done.So stick with some of those smaller like patterns for nymphing, you know, perdigon small Walt's worms. And terrestrial action is just starting to warm up. So we've got our greeny weenie hatch starting now.So definitely time to start throwing some greeny weenies around and ants, beetles, things like that. As we move into these warmer months here, those terrestrials will really, you know, come through for you on the fly front.
Marvin Cash
Yeah, and any kind of summer hatches, folks should be on the lookout for.
George Costa
Yeah, definitely cahills for sure. You know, summer hatches, we've got those, there's some bigger olives around right now. We've got like those size 16 Cornutas.Some of those are kind of floating around right now. Little summer quills. We saw a good hatch of them the other day.Um, you know, and the, if the fish key in on them, that's one thing or another, you know, but you just gotta really, if you wanna fish dries this time of year, really the evenings are gonna be your best bet.Um, you know, definitely some caddis around and it's one of those things where it could be one day you got a good hatch, the next day you're not seeing too much. But you know, you just gotta work the water, take your time with it and you know, right place, right time is gonna be getting your results.
Marvin Cash
Uh, gotcha. Anything cool going on in the shops?
George Costa
Uh, usual stuff. We've got our some bunch of sale stuff online, you know, check that out.Uh, we've got a good smallmouth coming up with Caleb here at State College towards the end of the month. There's still some spots open for that. He's going to be doing some top order smallmouth patterns. So definitely worth doing that class.If you want to learn how to tie some good flies with Caleb Rebarchak, that's a great little class. Bunch of good classes going on at our other shops too.Check them all out on our website, tcoflyfishing.com and then we've got our Bass Thumb Tournament coming up in July. We've got the All Fins In tournament coming up this weekend. If anybody, hears this before Friday and you've got a team you want to get on.We've got some spots open left spots left for that tournament coming up on Saturday and Sunday. That's a really fun time and it helps to benefit Clearwater Conservancy out here in central Pennsylvania.So check all that stuff out online at tcoflyfishing.com.
Marvin Cash
Got it. And you've got a store event, what like in August at one of your locations too, right?
George Costa
Yeah, we've got the fly fishing festival coming up at the Boiling Springs shop in August too. That's always a really good event we've gotten used to.We've been doing it at Allenberry, but this year it's going to be right on Children's Lake at our Boiling Springs location. And that's another great fun event to check out a lot of gear and that's coming up in August.
Marvin Cash
Very, very cool. Is it hot enough to knock you off your dark rum game and drive you to IPAs yet?
George Costa
Absolutely not. I'm not drinking no beer. That's not for me. I'm going to be on rum all summer.
Marvin Cash
You don't shift to like G&Ts or martinis or anything?
George Costa
Depends, really. Depends on the. Depends on the environment. But, you know, maybe. Maybe just a lawnmower beer every now and then.
Marvin Cash
A Juengling?
George Costa
Yeah, something like that.
Marvin Cash
Well, listen, folks, you know, we love questions on the Articulate Fly. It helps keep George happy. And that's very important, not just for me, but also for the folks in the shop, you know. So you like that, George?
George Costa
I do.
Marvin Cash
You know, he yells at people if he doesn't get questions. Folks, it's really pretty simple sometimes. Sometimes on days that end in Y. But if you email me or DM me on Instagram, happy to look at your question.If we use it, I'll send you some articulate flash swag. And we were in your drawing for something cool from the shop at the end of the season.And George, before I let you return to retail bliss, you want to let folks know location, shop hours and all that kind of good stuff.
George Costa
Absolutely. Here at state college, we are here Mondays through Saturdays 9 to 6, Sundays 9 to 3. All of our other shops have similar hours.And check us out online at tcoflyfishing.com on the world's wide's webs.
Marvin Cash
Well, there you go. Well, thank you, Internet George.
George Costa
Oh, you're very welcome, Internet podcast, Marvin.
Marvin Cash
There you go. Well, listen, folks, get out there and catch a few tight lines, everybody. Tight lines, George.
George Costa
Take it easy, Marvin.
