A bet on the tail risk of a sudden mass-casualty heat event in Texas. The most plausible path is a grid blackout during an extreme heat wave that knocks out air conditioning across a metro all at once, but the mechanism is not a resolution condition; any cause counts. This is the lower-threshold companion to an earlier 10,000-in-a-week market. The 10,000 bar is widely seen as too high to ever be provable, in part because Texas is known to badly undercount heat deaths on death certificates (see *Thousands of Heat-Related Deaths Go Uncounted in Texas*, deceleration.news). To get around that, this market explicitly counts modeled excess-mortality estimates, not just official death-certificate tallies. **Resolves YES** if both conditions hold for the same 7-day period ending before January 1, 2032: (1) a credible estimate attributes 2,500 or more deaths in Texas to heat, and (2) that window overlaps a verified extreme-heat event in the affected area, meaning a National Weather Service Extreme Heat Warning (formerly Excessive Heat Warning) or equivalent official heat designation was in effect. Otherwise NO. Modeled excess-mortality estimates qualify for condition (1), because direct death-certificate counts substantially undercount heat mortality. For scale: 2,500 heat deaths in one week in Texas is about 80 per million residents. Greece lost about 280 per million to heat across the entire summer of 2022, the deadliest European heat season on record (Ballester et al., Nature Medicine, 2023). The bet is whether Texas takes roughly a quarter of that toll compressed into a single week. The concurrent-heat condition exists to exclude unrelated mortality spikes. Deaths from a pandemic, hurricane, or winter storm do not count even if total excess mortality is high, because the figure must be attributed to heat and must coincide with a recognized heat event. Where credible estimates differ, resolution uses the figure judged most credible, applied to the 7-day window containing the event's peak mortality. "Attributed to heat" includes deaths where heat or hyperthermia is an underlying or contributing cause, and deaths identified as heat-related through excess-mortality modeling of a discrete event. Secondary-cause deaths during a heat event (for example drowning while cooling off) count only if the cited source attributes them to the heat.