Why is there no snow in neighbor hood view for sims 2...??? And the day/night toggle doesnt work!!!?

I have all the expansion packs installed and i've got some stuff packs...i dont remember when i realised the problem but IT IS REALLY ANNOYING. when the season is winter, the neighborhood view used to be all snowy, but now when i go to it and have a look, only the lots and neighborhood decorations are snowy, the ground stays green. Another problem is that when i press the neighborhood night/day toggle switch, the lots and decor turn dark but the ground still stays LIGHT AND GREEN....THIS IS EXTREMELY FRUSTRATING and i would appreciate any help...PLEASE HELP ME!!!