anything can be predicted with a certain margin of error.
But, the volitility does not follow a normal distribution, and the first step is properly determening / predicting Volatility is determining which distribution it follows.
Once you have that, you can begin to model.
If you use a Gaussian distribution - you *may* see good results for a bit, but the outliers will screw you. And, in reality, these aren't really outliers - they are part of the curve.
Not an easy task.