The Federal Reserve's next decision is due on Wednesday, October 28, the second day of the October 27–28 meeting on the Fed's published calendar. The statement comes at 2:00 p.m. ET and the Chair's press conference follows at 2:30. That fixed timetable splits the session into distinct parts, and the gamma map behaves differently in each. Implied vol into Fed days is covered in why IV spikes before Fed days; this post is about the intraday tape on the day itself.
The morning: compression near the money
Most FOMC mornings are quiet, and positioning is part of the reason. Traders who want exposure to the decision hold it in options that span 2:00 p.m., and a large share of that sits in same-day SPX options struck near the money. When dealers are net long that near-the-money gamma — typical when customers are selling premium into the event — their hedging leans against every move away from the strike. The result is a narrow, choppy morning that often hugs one or two strikes.
Two practical points:
- Range trades work until they don't. Fading the edges of a compressed FOMC morning has a decent record. Holding those fades into 2:00 p.m. does not.
- The pin is a sign of positioning, not a forecast. A market pinned at 6,000 at 1:55 p.m. tells you where the gamma is, not where price will be at 2:05.
2:00 p.m.: the volatility and gamma shift
When the statement hits, two things happen at once. Price reprices to the decision and the wording, and implied vol on the expiries that spanned the event drops sharply as the uncertainty resolves.
The vol drop changes dealer delta through vanna, as on CPI mornings: if dealers are short puts and implied vol falls, those puts lose delta and the short hedges against them are bought back. That is one reason a balanced statement often produces a grind higher in the first half hour.
The bigger effect on Fed afternoons comes from same-day gamma. By 2:00 p.m. there are two hours left on the 0DTE options. Gamma on near-the-money options rises sharply as expiration approaches, so the same-day strikes near spot carry far more gamma per contract in the afternoon than they did in the morning. That sensitivity cuts both ways:
- If dealers are long that gamma, the hedging snaps price back toward the big strikes and the post-statement move fades quickly.
- If dealers are short it — common when customers bought calls or puts to play the decision — the hedging chases price, and a move of a few points can turn into a large one.
The mechanics of that late-day gamma are the subject of 0DTE positioning mechanics and the 0DTE gamma guide.
2:30 p.m.: the second leg
The press conference regularly reverses or extends the first move. The difference from 2:00 is that by 2:30 the event premium is already gone. There is little implied vol left to collapse, so the vanna support that helped the first reaction is mostly spent. What is left is the gamma map and whatever the Chair says.
That makes the regime check at 2:30 the most important one of the day. Ask where price is relative to the gamma flip, now that the first reaction has been absorbed:
- Above the flip: moves on the press conference tend to be absorbed. The day often closes inside the range between the walls.
- Below the flip: moves tend to extend. A hawkish line during the press conference in short gamma is where the large Fed-day ranges come from.
The last hour
From 3:00 p.m. to the close, charm — the change in delta as time passes — becomes a big factor. Same-day options that are out of the money lose delta quickly in the last hour, and dealers unwind the hedges they held against them. On a Fed day, where the same-day open interest is heavy, that unwind can drive a late drift toward the strikes that carry the most open interest, or away from strikes that have just gone out of the money.
A hypothetical Fed afternoon
Say SPX spends the morning between 5,990 and 6,010, with the largest same-day strike at 6,000, the gamma flip at 5,960 and the call wall at 6,050.
- 2:00 p.m.: the statement is in line. Implied vol falls and SPX lifts to 6,025. Price is above the flip and has moved away from the 6,000 pin.
- 2:30 p.m.: the press conference is read as hawkish. SPX gives back the move and trades down to 5,995. It is still above the flip, so the drop slows near the big strike.
- 3:30 p.m.: charm pulls price back toward 6,000 into the close.
Now change one input: put the flip at 6,005 instead of 5,960. The same hawkish press conference takes SPX below the flip in short gamma, and the move to 5,995 becomes a move to 5,960. Same news, very different afternoon, and the map told you in advance which kind of afternoon was possible.
Sizing for the afternoon
The structure of a Fed day argues for different position sizes at different times. In the compressed morning, ranges are narrow, so stops are close and small positions risk little. After 2:00 p.m., the same position can see several times the movement in minutes, and spreads widen right when you would want to exit. A common approach is to trade the morning small, stand aside for the first minutes after the statement, and size the afternoon off the regime: modestly when price is above the flip and moves are being absorbed, smaller still when it is below the flip and moves are extending. Being flat at 2:00 p.m. is a perfectly good position.
FOMC day checklist
- Before the open: mark the gamma flip, the walls and the largest same-day strikes.
- Morning: expect compression near the big strikes. Trade the range lightly or not at all.
- 2:00 p.m.: let the first minutes pass. Note where price settles relative to the flip.
- 2:30 p.m.: re-check the regime. Above the flip, expect absorption; below it, expect extension.
- After 3:00 p.m.: watch for charm-driven drift toward the heaviest same-day strikes.
The Fed's December meeting is on December 8–9, and the same structure applies. To watch the flip and walls update through a Fed afternoon, see GEXRadar's plans.
For educational and informational purposes. Not financial advice; options trading involves substantial risk of loss. All prices in this post are hypothetical. Meeting dates are from the Federal Reserve's calendar.