A) You will not see your shadow tomorrow, because it will be snowing and therefore cloudy.
B) You will be wrong. Because you will be not seeing your shadow in the middle of Snowpocalypse or Snowmageddon or Snowmicide or Snowlocaust or Snowsterf**k or something.
This will be the norm. Historically, groundhog accuracy rates, of Phil and others across North America, tend to come in somewhere around the high 30's overall; Phil himself is showing at 39%. You'd do better flipping a coin, or flipping the signs: shadow means spring, no shadow means winter.
Proponents will tell you not to pay attention to the numbers and to just have fun with it. You know what's fun? Not going out in a blizzard.
Meanwhile, towards our neck of the woods, in Sun Prairie, Wisconsin, Jimmy the Groundhog- generally the groundhog of record should Phil prove unable to perform his duties- will be giving the same prediction in the middle of a 20-inch snow dump "capable of paralyzing parts of southeast Wisconsin."