With all this snow and ice, you may get leaks when it starts to melt but its nothing to worry about if it leaks only when it snows and gets below freezing. Freezing water expands and gets up behind the flashing and shingles. Especially when the snow is thick and high. If it is higher then the flashing around your skylights then you will most likely see water coming into your house. Flashing is designed to keep rain out, and skylights are vented, so don’t worry. If the leaks persist, then have a licensed contractor check it out.