The reason is that the block reward halving is approaching.  It is sensible logic to assume the price will double in anticipation.  We saw a low of around $180 recently, so I think that the price going to $360 in the next 9-12 months is a reasonable assumption.

A more bullish explanation might be that the Winklevoss twins' new exchange brought many of their rich friends off the sidelines to begin accumulating bitcoins in anticipation of the COIN ETF being approved.  The COIN ETF has the potential to dump billions into the Bitcoin market, at which point an optimistic price point would be $2,000-$4,000.

Either way, I believe the markets are seeing that the worst is over.  The reward now outweighs the risk and money will flow appropriately.