US lightning detection rules, which automatically suspend matches if strikes occur within eight miles of open-air stadiums and reset a 30-minute wait clock with each new detection, represent the dominant factor shaping expectations for weather-related stoppages at the 2026 FIFA World Cup. Summer thunderstorm patterns across US host cities heighten this risk compared with prior tournaments, as seen in recent warm-up fixtures like England versus Costa Rica that faced hour-long delays from heavy rain and electrical activity. FIFA lacks a fixed abandonment threshold, handling postponements case-by-case while following local protocols, and group-stage scheduling overlaps could amplify impacts if conditions persist into later rounds. Heat-related cooling breaks under Wet Bulb Globe Temperature monitoring add another layer but rarely trigger full suspensions.