The useful comparison is JPMorgan's scenario range versus option pricing
The Federal Reserve's September meeting concludes on Wednesday, September 16, with the policy statement scheduled for 2:00 p.m. Eastern Time and the press conference at 2:30 p.m. The market has moved rapidly toward a quarter-point increase after hotter inflation data and a rise in oil prices, making the size of the first policy move less unusual than the uncertainty around what Chair Kevin Warsh says about the path afterward.
That distinction matters because JPMorgan's trading-desk framework and the SPX option market are describing different objects. JPMorgan laid out five possible policy-and-communication combinations with estimated S&P 500 reactions ranging from roughly a 1% gain at the upper end to a 2% decline at the lower end. Cboe, meanwhile, reported on September 14 that SPX weekly options were pricing about a 1.1% implied move for the Wednesday announcement.
The research question is therefore not whether one estimate is right and the other is wrong. It is whether the option market is mainly pricing the central part of the distribution while JPMorgan's most extreme cases describe lower-frequency tail outcomes that can sit outside that implied event move.
Most of the five scenarios fit inside the 1.1% event envelope
The five-case framework is useful because it separates the rate decision from the communication regime. A quarter-point increase with little additional guidance was associated with an estimated S&P 500 rise of 0.25% to 0.75%. A quarter-point increase accompanied by a faster reversal of the Fed's 2025 easing was associated with a 0.50% to 1.00% rise. A quarter-point increase paired with a higher neutral-rate discussion was associated with a 0.25% to 1.00% decline.
Those three ranges largely fit inside Cboe's roughly 1.1% SPX implied move. That is important because the consensus outcome is not mechanically the same as a low-volatility outcome. Even if the policy rate changes by the expected amount, the market can still reprice the expected terminal rate, the neutral-rate debate, the shape of the Treasury curve, and the degree of future guidance.
The two outer JPMorgan cases are different. A decision to leave rates unchanged was associated with an estimated 1.25% to 1.75% S&P 500 decline, while a quarter-point increase accompanied by language implying that the policy rate needs to move materially higher was associated with a 1% to 2% decline. Parts of both ranges sit beyond the 1.1% option-implied event move.
That does not establish that SPX options are understating the event. An implied move is not a maximum permitted outcome, and the five JPMorgan cases are scenario estimates rather than a probability-weighted distribution. A market can rationally price a central event magnitude near 1.1% while still allowing for less frequent outcomes substantially beyond it.
Skew shows that the distribution is already asymmetric
The more revealing part of the option surface may be the shape rather than the headline volatility level. Cboe reported that one-month SPX put skew rose to the 73rd percentile of its historical distribution as hedging demand increased. The VIX Index also rose during the prior week, and Cboe said more than half of that increase came from steeper SPX skew and convexity rather than a simple parallel rise in volatility.
That pattern is consistent with a market assigning more premium to downside tails without requiring a view that the central outcome must be negative. This distinction matters when comparing the option market with JPMorgan's scenario framework. The two most severe cases in the bank's analysis are both downside cases, and the option surface already appears to charge more for asymmetric downside exposure than a single 1.1% event number can show.
Cboe also reported unusually large VIX call activity in the two weeks before the meeting, including three of the four largest VIX trades of the year. The observable fact is that demand for volatility protection increased. The activity alone does not reveal a complete portfolio view because option positions can serve several purposes across hedging, relative-value, and multi-leg structures.
The event has shifted from a technology question to a macro-volatility question
Another useful clue is the relationship between index and single-stock volatility. Cboe reported that the spread between one-month QQQ and SPX implied volatility had fallen to about 3.6%, near a one-year low, while the gap between single-stock and index volatility had narrowed sharply from its July peak.
That suggests the dominant uncertainty has moved away from company-specific earnings and AI narratives toward shared macro factors such as inflation, rates, oil, and policy credibility. For an FOMC event, that is exactly the kind of regime in which an index-level option surface can become more informative than a collection of individual technology names.
The Treasury market reinforces that interpretation. On September 15, Cboe noted that the 10-year Treasury yield had moved above 5% for the first time since 2007 and that the 30-year yield was around 5.37%. Reuters similarly described the meeting as one in which the policy decision and Warsh's communication could interact with an already stressed long end of the curve.
JPMorgan's no-change scenario is therefore best understood as a transmission hypothesis rather than a simple equity forecast: if a pause causes investors to demand more inflation compensation or term premium, longer-dated yields could rise even though the policy rate itself does not. The equity response would then be transmitted through discount rates and broader financial conditions rather than through the 25-basis-point decision alone.
The post-meeting test is whether volatility collapses or migrates outward
The strongest follow-up test comes after the announcement. If the policy decision resolves the uncertainty concentrated around September 16, the event premium embedded in very short-dated SPX options should decay quickly. That would be the classic event-volatility pattern: uncertainty is concentrated around a known timestamp and then disappears once the information is released.
A different outcome would be more informative. If short-dated event volatility falls but one-month skew remains elevated, the market would be saying that the meeting resolved the immediate binary question without resolving the downside distribution. If volatility remains firm across later expirations, the interpretation would shift again: the meeting would have revealed a more persistent policy regime rather than a one-session event.
The Treasury curve provides a second test. A quarter-point increase that is followed by calmer long-dated yields would support the idea that tighter near-term policy can reduce inflation-risk pressure farther out the curve. A meeting that leaves the 10-year and 30-year yields under renewed pressure would suggest that the market is still debating the neutral rate, inflation credibility, or term premium even after the policy action is known.
JPMorgan's five cases are better treated as a map of tails
The main value of the five-scenario framework is not the individual S&P 500 percentage attached to each branch. It is the way the framework identifies which part of the policy message changes the distribution.
Cboe's roughly 1.1% SPX implied move captures the event magnitude embedded in weekly options before the meeting. JPMorgan's central scenarios mostly fit inside that envelope, while its two most severe downside cases extend beyond it. At the same time, elevated put skew shows that the option market is already distinguishing between average volatility and downside-tail pricing.
That combination makes the September meeting a useful case study in why an implied move should not be read as a complete forecast. The headline number describes only one dimension of the surface. The more durable research problem is whether the meeting changes the shape of the distribution, the persistence of volatility across expirations, and the relationship between equity volatility and the long end of the Treasury curve.