Rand for a month of weather changes

I have built a worksheet for a calendar month that can have 1 of 4 weather conditions, snow, cloudy, sunny or rain. I put the =Rand() in column B, and I have used the IF and OR function in Column C to write the formula but it doesn't seem to work when I filter it down the entire 31 days and hit PF9, the weather condition doesn't show. If someone can assist me where I might have missed something in the formula I would appreciate it. I have attached the problem (see Exercise 15-4) tab.