Get three sturdy branches 3 ft long. Tie a strong string at the top making a tripod. Tie the string around a 2 lb rock and let it dangle at the base of the tripod. Set the "forcaster" out in the open.
1. If it's windy, the rock will swing.
2. If it's sunny, the rock will cast a shadow.
3. If it's raining, the rock will be wet. (substitute for snow)
4. If it's dark, you can't see the rock.