Sorry it took so long to get back to you, I've been trying to get as much time as possible in ice fishing before Sunday's rain melts it off.
I meant water temperature, air temperature doesn't directly effect them. Often the air temperature varies greatly during the early spring, so it's hard to guess much based on that. You can catch bass any time of the year though, I have just noticed a decrease in activity level below 45 degrees.
Got out ice fishing on Wednesday, Thursday afternoon, and today. Spent the first couple hours drilling holes on Wednesday trying to find the catfish hole again, but I couldn't find them. My depth finder doesn't have a GPS, so I can't drop waypoints with it. I tried to do it the old fashioned way by triangulating it, but apparently my triangulating skills are pretty bad. Gave up around noon and switched to crappie and bluegill fishing. I found them in 16 feet of water with quick access to deep water (in that little pocket by the dam Brian), all of them hugging bottom. We caught a little of everything there, about sixty bluegill and warmouth, five nice crappie, a four nice largemouth (who says you can't catch bass through the ice), and some white bass. The majority hit a 1/100 ounce horizontal jig with an atomic wishbone and a wax worm fished with a steady pounding/vibrating motion near bottom, but some ate minnows, blood worm imitations, panfish asassins, etc. Ended with a total of 75 fish for the day, a great day on ice in my book.
Managed to make some time to go fishing yesterday afternoon again, but only for a few hours. This time I fished the opposite end of the lake from where I was yesterday, toward the upper end at the opening of a cove with scattered brush on the edge of a flat. Caught 22 big bluegill, 3 white bass, 2 largemouth, and a 15 inch walleye in that spot, the bluegill and bass in a horizontal jig with a wishbone plastic and a wax worm kept still right above the bottom, and the white bass and walleye hit a minnow. The first two walleye I've ever caught at this lake in a year and a half of fishing it, and they were within three weeks of each other for whatever reason.
Got out ice fishing today, again fishing the upper end of the lake. Started out at the same spot, and right off the bat got some big bluegill and a solid 17 inch largemouth. That bass put up a challenging fight on four pound line and a light powered rod, it felt bigger than a lot of the 3-4 pounders I've caught. Then it shut down, so I moved around the lake for an hour or two looking for some more, but had nothing to show for it. Walked back to the same spot I had fished earlier around 4 o-clock. The fish were hitting big time now, they usually bit as soon as I picked the jig off the bottom from the initial drop. Went from only a dozen fish to 55 big bluegill in only an hour and a half, the frozen rain mixed with pea sized hail that came down for the last 45 minutes didn't even seem to bother them at all. Wasn't a whole lot of fun to fish in the hail, but it was mostly freezing rain, and the eight to nine and a half inch bluegill made it all worth it.