Channel quality prediction is important for many networking mechanisms. This paper considers long-term prediction with the prediction distance of some hundred milliseconds. The prediction works in the context of Adaptive Coding and Modulation, which actually converts the task of continuous value prediction into discrete value prediction. In this work, pattern management is also considered as a key mechanism to reduce memory and processing overheads. Performance evaluation is carried out using measurement traces to evaluate the prediction algorithm with different parameter settings and matching measures.