Snow or shine
Winter weather can be up-and-down with days of snow and days of sunshine. Taking advantage of the "good" winter days can pay off for curing some of the winter blues.
What would I consider a "good" winter day to attempt fishing? Well, that definition is a little different for everyone. What I consider a reasonable day to attempt fishing, and more importantly, have a legitimate shot at catching fish is this:
Air temps in the upper 30's or higher.
Preferably higher. I won't personally waste my time if the temperatures are going to be sub freezing, or if the day's highs will only be above freezing for a short period of time. I've fished in just about every conceivable temp all the way down to one degree... those days are over for me.
Sudden drop in temperature.
A sudden drop in temp can cause the fish to slow down, if not become lockjaw.
A series of warmer days.
If air temps have been extremely cold for a number of days, the first warmer day may not be as ideal as the 2nd, 3rd, or more. The longer the water has the opportunity to warm up the better, every degree helps!
Is the river full of ice?
This relates to the above comment on a series of warmer days. If air temps, especially night temps have been plummeting into the 20's odds are high that the river is choked with ice. If there are no current reports for a river keep this into consideration and don't be too upset when you arrive to see ice instead of a free-flowing river.
Light to no wind.
Preferably zero wind. Windchill is a buzzkill during the winter. The beautiful 40 degree day can feel like 30 real quick. That being said, wind doesn't stop fish from feeding so it's up to you.
Changing weather conditions will more than likely turn trout off.
Sunshine is nice, but not necessary.
Sun warms the water and can certainly help out the cold temps, but the reality is overcast days can be even better fishing in most areas.
We hope you are surviving the winter blues. If you find yourself needing a fish fix, take these thoughts into consideration if you are hoping for a successful outing. Remember though, these are just some of my preferences for ideal winter conditions, trout can be caught in all sorts of adverse conditions... it's just up to your level of tolerance!