Heat and lightning: each body's policy, with its date.

World Lacrosse

Heat and hydration at championships

World Lacrosse's "Heat / Hydration Policy Statement / Procedural Matters" for its championships is marked version 4 and dated 11 July 2014. It says it was drawn up with expert advice to remove subjectivity by monitoring the Wet Bulb Globe Temperature (WBGT), which it calls the most widely used index of heat stress. It sets three levels:

The chief bench official, or the head referee if there is none, runs the breaks. The policy states that the risk of exertional heat illness is reduced but not removed even at the lowest level.

On 23 October 2026 World Lacrosse's health and safety page linked the IOC consensus statement on sport events in the heat rather than any newer World Lacrosse heat policy, and listed no lightning or weather policy. Whether the 2014 policy is still in force is unconfirmed. The women's field rule book (2025-2026 v1.0) appends World Championship policies on blood, game interruption, and heat and hydration (Appendices E to G); their texts are not summarised here. Version 1.1 of the women's book (March 2025) exists but was not read.

Lightning in the men's field rules

World Lacrosse's men's field rules (2025-2027 v1.0, Rules 30.1 and 30.2) require play to be halted, and everyone to go indoors, when the Head Official or the tournament Official-in-Chief judges that lightning or electrical storms make continuing unadvisable. A later version, 1.1 (January 2026), exists but was not read. No lightning provision from the box or sixes books is recorded in the research for this site.

NFHS (US high school)

Lightning

The NFHS Sports Medicine Advisory Committee's "Guidelines on Handling Practices and Contests during Lightning or Thunder Disturbances" were last revised in October 2024, after editions in January 2021, March 2018, October 2014, January 2014, October 2010, October 2007 and January 2004. They describe themselves as a default policy, and name the state association and the nearest National Weather Service office as the preferred sources for a facility's own policy.

• Suspension. When thunder is heard or lightning is seen, play is suspended for at least 30 minutes. It resumes only 30 minutes after the last thunder or lightning, and any new thunder or lightning restarts the count.
• Detection networks. Where a national lightning detection network is available, play is suspended when lightning is within 10 miles; the guidelines add that seeing lightning or hearing thunder always takes precedence over an app or detector.
• Preparation. The guidelines call for a named staff member to monitor the weather, an emergency action plan, an annual review of the policy with staff, and informing athletes and parents at the start of each season.

Heat

The NFHS committee's position statement on heat acclimatization and heat illness prevention is dated October 2025, after editions in April 2022, April 2018, April 2015 and April 2012. It states that exertional heatstroke is the leading cause of preventable death in high school athletics, and that the greatest risk comes in high-intensity, long or repeated same-day practices in summer or hot weather.

The statement is a guiding document for state associations. It accepts that no single acclimatization plan fits every region, strongly encourages states to adopt all of its "Fundamentals", which include introducing protective equipment such as helmets and pads progressively over the first practices, and refers to WBGT readings for hot and humid weather. Like other NFHS position statements, it carries a disclaimer that it is not exhaustive and is no substitute for consulting appropriate health-care professionals.

USA Lacrosse

USA Lacrosse's health and safety page (read 23 October 2026) lists Lightning Guidelines dated 2023 and an Emergency Action Plan resource. The guideline documents for 2022 and 2023 returned errors when the research tried to open them. Search summaries report that they use a 5-nautical-mile radius from the venue for delaying or suspending play and call the flash-to-bang counting method unreliable, and that an older USA Lacrosse policy used 6 miles and a 30-minute suspension. Those figures are unconfirmed.

The distance triggers differ. The NFHS's 2024 default policy uses any thunder heard or lightning seen, or lightning within 10 miles where detection data are available. USA Lacrosse's guidelines were reported to use 5 nautical miles, and its older policy 6 miles.

NCAA (US college)

"Preventing Catastrophic Injury and Death in Collegiate Athletes: Interassociation Recommendations Endorsed by 13 Medical and Sports Medicine Organizations" was published in the Journal of Athletic Training. Its endorsers include the NCAA, NATA, the American Medical Society for Sports Medicine and NOCSAE. It covers six areas: sportsmanship, protective equipment, acclimatization and conditioning, emergency action plans, the responsibilities of athletics staff, and education and training. A search summary says the NCAA Board of Governors endorsed these recommendations as association-wide policy in 2019; the NCAA page returned an error, so that is unconfirmed.

No NCAA lacrosse-specific lightning or heat rule was found, and the NCAA rule books were not read.

Not covered

The research for this site recorded no heat or lightning policy from Lacrosse Canada, England Lacrosse or Lacrosse Australia, so none is described here. How officials run a game is on officials.