Well for one thing freezing and thawing loosens the soil and the ground lacks vegetation which helps hold the soil and also reduces the impact of rain drops as does the tree leaves. Causing more runoff. The cold water is denser and holds matter in suspension more than warmer water. There are probably a couple more factors. Also underwater springs will be bubbling up enough to disturb the bottom sometimes, and water seeps on the bank can continue to cause runoff for several days after it rains.
Don't let it hold you back...fish can be caught. It use to discourage the heck out of me but now I just adapt. The murkier water warms faster when the sun shines than clear water. When the shallow water starts warming from the sun and some wind blows across it plankton will get concentrated,the baitfish will move in and some fish will follow. Try some of the brightest clown color chartreuse jigs in these conditions they can see them pretty good. A dark color with a bright chartreuse tail adds contrast and works good. Also Pink and a dark color too. Sometimes they like a moving lure and sometimes slow under a cork will work,sometimes both in the same place. If its closer to bedding time and you have a lot of shoreline wood use a longpole to dip in close to it
Forgive me I'm rattling on about a bunch of stuff you didn't ask and you may already know.