Welcome to the forum, and Minnesota, when you get here. Portage lake is one that will require a Trout stamp to fish as it is a stocked lake with Splake, A cross of brook trout and a Lake trout. Good eating, fun in light tackle to catch.
As for you with lakes, Northern pike maybe your main fish being caught, fish deeper using jigs and plastic grubs, minnow style plastics and lures that can run a bit deeper. But then some walleyes could near a sandy/ gravel areas.
The pike will be near the weeds, A few of the lakes have bluegills /sunfish, which are very good eating. Small bites, grubs and even trout flies work for catching them.
Bring lots of bug spray, as by then the flies and skeeters will carry you away. Have a great time, Enjoy the loons.

I live in Minnesota, but can relate, Only we have days of dam cold weather. Like rain it all comes down to having the correct clothes and footwear. Rainy weather can be both great fishing and really bad. If you have thunder and Lightening Stay home. People die in this crap, thinking they are going to get that trophy of a life time. Doesn't matter if you caught? when you're dead. Light rains, over a steady rain fall, come get them. Even if you are a bank/ shore fishing these fish will eating. The rain covers you movement, plus you can use those larger baits, I have used large top water lures during a light rain and caught some of my PB, fish.
Same in colder weather days fish will go deeper, then go with medium size lures, or even scale down a little with slower baits. We go out on days when it's -20º during the weather and knock'em died.

The big point on North side middle of the lake, try a drop-shot rig with crappie minnows and Wax worms or panfish leeches. Leeches will get the bigger gills. At that time of August fathead minnows run small, and could get the nicer Crappies.

Consider the channel area southeast of the island, and the other channel just north of the bridge. As for baits. Try crankbaits trolling long lined, also spinners with weight that will get you within two feet of the bottom, 6- to 75 feet behind the boat. If the traffic light, use a in-line planer board. Get lures away from the boat.

MH, I hope you brought some small hooks to catch a few of those Canada walleyes for eating, between chancing the big skies. I fished Manitoba 10 years ago. We were hoping for a couple giant pike or a musky. None wanted to come play, So, no photos to create a replica from. But the walleyes made up the difference, in one day our
counter hit 250 walleyes. That evening we each kept 3 walleyes for a fish fry. All other fish were released unharmed other than a small hole in lip. Manitoba is a NO barb on hook, area.

I am a fishing guide based in Buffalo, MN

My question is do you have a boat or just shore fishing? This can limit where you can go to fish. I would go to the local library for boats on fishing the twin cities area. Sybille Smith has a great book plus she has even shows places for shore fishing. Sybille has also done a shore fishing map for around the twin cities.

With the Walleye fishing closed, Now is a good time to find the biggest walleyes with 8 inch musky lures. Used a
3 oz snap weight, troll around in twenty five ft of water. It is amazing the amount of big fish a person can catch.
The worst that can happen you catch a 50 inch musky.

Look to deeper weed edges, also if you have a a good fish located, watch for suspended fish. This could be fish 12 to 18 ft down over 20 to 35 ft of water. My uncle had a resort on Rice Lake, we were there several times, during the summer.

Those are a perfect bunch to melt into new new baits. Check out Larry Dahlbergs lure making, Many times I don't get all worried about the scent in plastic baits as several times I'm fishing these lures as trailers and on jigs. You can
produce your own lures from puddy or clay. After making your POP mold. remove your sample, coat the inside of POP mold with Vaseoline. Placing a paper towel over you Pyrex cup holds the fumes from inside your microwave, I have
older small microwave, that I use for my Taxidermy and fishing projects.

Cooking the scent out may be ok, As I soak mine back in new scent. You can also add anis oil in the melted plastic.
Then I store them in freezer bags, per color. I have colored worm bags for different types of plastics.

Betts, DO NOT, throw away any of your plastic worms, Senkos or whatever they are. As you can
melt them down in a Pyrex measuring cup in the microwave. Watch the mixture as it melts at 350º

You can make your own mold using plaster of paris, copying a plastic that you use most.

Fish are semi-smart, but as you are talking seems like a bass tournament fish. These may find there way back there place they were caught. But at may take several months. Now fish do move 20 plus miles for spawning such as walleyes, but they will turn to their place they started after the spawn is over.
I guide on a 5,000 acre lake, and I feel the bass tournaments have made fishing really screwed up. Smallmouth Bass, caught from one area being moved and released in another. total fish schools have been moved. the other thing I have found is having dozens of fish released in one area, will really stress fish, due to food supply, as well as area where fish will feel safe.

Casting lures in a pool is a great way to seeing how it swims. If fishing jigs, worms, and other bottom baits. It does help you understand how much your lure moves when you retrieve them.

Call Tom Neustrom, he guides up in that area, Tom is also on Reel Outdoors radio show on Sunday evenings. You can listen to past shows on BOB -FM 106 country, from Ramsey, MN. If you call say you heard their show, and your wondering what the local report is.