there is no "fixed rule" on how vol skew will behave in certain condition they are simply reflecting demand and supply from all market participants during high volatility periods: - front month vol skew can rise (vertically) and steepen at the same time ex: pre-election - or it can rise and flatten ex: second day post-brexit - or it can fall and flatten ex: early morning on nov 9th trader can monitor vol skew changes via IB volatility lab or other vol platforms how it changes through the days.. how it changes relatively to other expirations.. after a while, trader may develop a general idea/ bias on how vol skew likely to behave and then use the information to improve one's trading setup / existing positions :]