Not a wise idea, but your gonna do what you want anyway. While its not the alcohol itself that generally gets stored as fat, as MS said any fat ingested and possibly carbs if glycogen if filled will go directly to fat storage. Alcohol is poison to the body and must be completely eliminated from the body before any other fuel (glucose, fats, ketones) can be used as an energy source. Now take into account that beer has carbs and empty calories, excess calories for the day and the body will store add bodyfat. Hard alcohol generally has sugars added which again are calories and sugar is shit anyway, more potential fat storage. Drink mixed drinks with juice/soda, etc., if theres carbs more calories, potential fat storage. Alcohol can decrease testosterone for several days and raises estrogen as well as cortisol. A perfect environment for more bodyfat accumulation and muscle loss, as well as less muscle gain.
Again, do what you want and most people choose to enjoy themselves, especially on weekends which is understandable, but you should know whats going on and what effects it will have on your weight lifting and dieting efforts.
On that note if possible Vodka is your best choice if you drink according to Charles Poliquin.