Around certain holidays — the day after Thanksgiving, Christmas Eve, July 3rd — the market closes early, typically at 1pm ET. These half-days run on thin, distorted volume, and the usual playbooks need adjusting or shelving.

Why half-days are tricky

Low participation means the levels are less reliable — a pin or a wall computed on thin flow holds less firmly, and moves that start can overshoot on little volume or fizzle for the same reason (the lunch-lull problem stretched across the whole day). The session is also compressed: the “power hour” and the close arrive early, so the day's arc is squished into a few hours.

The playbook: small or sit out

Default to reduced size or no trades. If you do trade, respect that levels are softer — demand more confluence, take smaller targets, and don't overstay. And remember the close comes early: the theta cliff and widening spreads hit around midday, and any in-the-money 0DTE still auto-exercises — be flat well before 1pm.

A half-day is a thin, warped, compressed session. The edge is usually in trading it smaller — or not at all.

The honest take

There's rarely much to miss on a half-day. The professional move is often to enjoy the holiday and keep your capital dry for a normal session. If you trade, treat the thin tape with extra suspicion and let the compressed clock, not just price, drive your exits. NoVo's discipline — smaller conviction in low-quality windows, and a one-click exit to get you flat before the close — fits a half-day naturally.