Weather forecasts help us to live our life. We plan a schedule with reference to the weather forecast. Populations of internet would have helps if this kind of information was offered. Therefore, I propose a study on a cyber weather forecast. There are many components on a cyber weather forecast like weather forecasts. Especially I propose the traffic volume forecasting model for cyber weather forecasting. This can help us to prepare actions about the harmful network traffics. In this paper, I will give the traffic volume forecasting model based on linear time series model and non-linear time series model.