For professional meteorologists, this is learned in the third of four college years in a meteorology degree program. In general, low pressure areas occur at all levels below about 40,000 ft. Intense storms systems, or low pressure regions, are vertically linked through a greater depth than the weaker system typically. If you look at different horizontal slices in the atmosphere, you can find the area of low pressure at each level typically. The weaker systems may only have low pressure at mid-levels and no surface reflection.
Air flows around a low pressure region counter-clockwise in the northern hemisphere.
The explanation is quite complex. This is one reason air speeds are typically stronger above the surface. In some cases, lake effect snow can produce some of the largest snowflakes observed due to the shear magnitude of the moisture involved and the temperature structure of the near-surface air. Many flakes stuck together gives the appearance of one large flake. To answer your question, no there really is no way to differentiate lake effect snow from other snow based on the flakes alone.