Heat

One hot afternoon rarely breaks a business. A week of them does: crews stop at noon, grapes burn, cooling systems run flat out and bills double. The Heat policy therefore counts degrees over a week. Each day, take the highest temperature of the day, subtract 34.5 °C, and keep the result if it is positive. Add up any seven consecutive days. That sum is the index.

Tier 1 starts at 18.4 °C-days and pays 25 % of the limit; for example, seven days at a maximum of 37.1 °C gives 18.2, just under, and a single extra degree on one of them crosses it. Tier 2 starts at 27.9 °C-days and pays 50 %. Tier 3 starts at 41.3 °C-days and pays the full limit. The window rolls day by day, so the worst week counts, not a calendar week.

Temperatures come from the station nearest your site, checked against reanalysis and a satellite surface-temperature estimate. Stations near buildings read warm, and a shaded sensor reads cool, so the policy lists the station by identifier and keeps it for the whole policy period. The calculation agent signs only when the station and reanalysis stay within 1.2 °C of each other over the week.

Prevention for heat arrives early because heat waves are well forecast. The alert goes out when a seven-day forecast gives your cell more than a one-in-three chance of crossing Tier 1, with the forecast daily maxima laid out day by day. For outdoor employers, it comes with a summary of the shift patterns that other insured sites switched to in similar weeks. The policy does not pay less if you take them.