The price of an at-the-money straddle (buying both a call and a put at the same strike) is the market's direct forecast of how big a move it expects — a clean, real-time read on the expected move around any catalyst. Learning to read straddle pricing lets you see the market's own bet on an event's magnitude.
Why the straddle is the forecast
A straddle profits if the underlying moves far enough in either direction to exceed the combined premium paid. So its price is the market's estimate of the move: the total cost of the ATM straddle approximates how far the market expects price to travel by expiration. If the SPY straddle for an FOMC expiry costs, say, roughly 1.5% of price, the market is pricing an expected move of about that magnitude. It's the IV ramp expressed as a dollar figure.
What it tells you
The straddle price gives you a concrete expected range for the event — useful for gauging how big a reaction is anticipated and where the market thinks the boundaries are. It also sets the bar for event option trades: a long option (or the straddle itself) only profits if the actual move exceeds the priced-in expectation (and survives the crush). If you think the move will be bigger than the straddle implies, options are “cheap”; if smaller, they're “expensive.” The straddle turns the abstract into a tradeable number.
The straddle is the market showing its hand: this far, it says, in dollars. Beat that number and long options win; fall short and the crush takes them.
Using it as a scalper
Even if you never trade a straddle, its price is a valuable read on how much move is expected around a catalyst — context for your expected-move boundaries and for judging whether a post-event reaction is large or small relative to expectations. It complements the VIX and term structure as ways to read priced-in volatility. NoVo maps the expected-move range on your chart; the straddle is the market's own version of that forecast.