Icicles have formed on the edge of your roof (with or without gutters) or icicles have formed behind your gutters.

Ice is building on top of the gutter or the lower edge of the roof. Ice dams as little as 1" thick can cause problems.

Ice is coming through the soffit vents or directly through the soffits.

There is ice or water on your siding or exterior wall surface. If the ice/water is an odd color (yellow-ish), it is water that is coming from inside your home through your exterior walls.

There is ice or water inside or around your window frames.

Ceiling and/or wall stains have appeared.