Enhanced ONH / ONL Auto Levels (Fixed Alerts)

This script automatically identifies and plots the Overnight High (ONH) and Overnight Low (ONL)—two of the most important liquidity levels for intraday futures and index traders.

The indicator scans the entire overnight session (default: 18:00–09:30 EST for ES) and records the highest wick and lowest wick formed during Globex. These levels are then projected into the regular trading session, giving traders clear reference points for potential reversals, breakouts, liquidity grabs, and high-probability retest setups.

ONH/ONL levels act as magnet zones, liquidity pockets, and institutional decision points—commonly targeted during the opening drive and London/New York overlap. Whether price sweeps, reclaims, or breaks these levels, the reaction often creates reliable trade opportunities for scalpers and day traders.