Identifying "high relative volume" in pre-market

[JasonH 47]

In @Andrew Aziz's Advanced book, when discussing Stocks in Play , there is an emphasis put on stocks with high relative volume. The example used is for KORS (pg 70), which shows three days out of about 90 days that clearly had higher volume compared to the others.

But how does a trader know a day like that is coming when looking at pre-market activity? Do we just assume that if it traded >50k-100k shares pre-market, that it's going to be relatively high volume day for that stock?