The increase of wind penetration into electric power system creates challenges to power grid management due to the variable nature of wind. The information provided by wind power forecasting is thus essential to the strategic deployment of electricity generating resources and can help operators to maintain electrical grid stability and to bid in electricity markets. Much recent research in wind power forecasting has been focused on predicting large, sudden changes in wind power output, called wind ramps. This paper aims to provide additional probabilistic information of wind ramp occurrences to end users. The temporal uncertainty of wind ramp occurrences is addressed using power scenarios generated from quantile forecasts of wind power and using a logistic regression technique. The proposed strategies were tested on four wind farms located in southern Alberta, Canada. Through calculation of BSS score and reliability diagram, the proposed method was proved superior to climatology forecasts, and was able to help operators judge the uncertainty of wind ramp forecasting.