The Busan prediction market asks whether the city's highest temperature on May 18, 2026 will reach exactly 26°C—a very specific outcome that explains the 1% odds. Busan in mid-May typically experiences temperatures in the 18–25°C range as spring transitions toward early summer, making 26°C a plausible but not dominant scenario. The market's extremely low odds suggest traders believe hitting that exact threshold is unlikely; weather systems rarely land on precise numbers. Historical temperature data for Busan shows that while 26°C highs do occur in mid-May roughly 10–15% of years, the probability of hitting it on any given day is constrained by natural weather variability. The current price reflects deep skepticism about this exact outcome, though regional high-pressure systems or warm air masses moving north could elevate temperatures toward that level. Traders are pricing in the inherent difficulty of weather prediction and the requirement for an exact match rather than a range.
What factors could move this market?
Busan, South Korea's largest port city on the southeast coast, has a temperate maritime climate moderated by the Korea Strait and East Sea. In mid-May, the city transitions from spring toward early summer, with average highs around 22°C and typical ranges from 18–25°C. The city's coastal location limits extreme temperature swings compared to inland regions, and May remains characterized by variable weather patterns as the Pacific anticyclone has not yet established dominance. Cold fronts and upper-level troughs remain common, frequently bringing cool, moist air from the north. Reaching 26°C requires specific atmospheric conditions: a high-pressure system from the Pacific, warm air advection from subtropical regions, clear skies for strong solar heating, or sustained southerly winds bringing maritime warmth. Conversely, typical spring variability, cloud cover, precipitation, or northerly flow would keep temperatures below that threshold. Historically, when Busan does experience 26°C+ highs in May, they cluster in the final week as summer heat gradually encroaches; mid-May occurrences are significantly rarer. The market's 1% odds reflect traders' conviction that hitting exactly 26°C on May 18 is extremely unlikely, not merely uncommon. Unlike range-based temperature markets, exact-outcome prediction requires precision approaching the limits of weather modeling and atmospheric chaos. Even skilled meteorologists struggle to forecast exact temperatures more than 7–10 days ahead; random variability dominates such timescales. The low liquidity and modest volume indicate this is a specialized market for weather enthusiasts testing probabilistic boundaries. As May 18 approaches, odds will tighten as forecasts converge, but the fundamental mechanical difficulty of hitting one precise value means odds will likely remain depressed unless an unusually stable, predictable weather pattern emerges.
What are traders watching for?
Official Busan high temperature reading on May 18 from Korea Meteorological Administration.
Cold front passage timing and upper-level trough movement across the Korean Peninsula mid-month.
Subtropical high-pressure system buildup and warm air advection from the south through May 18.
Sea surface temperature anomalies and Pacific jet stream positioning during the critical forecast window.
How does this market resolve?
Market resolves YES if the official highest temperature recorded in Busan on May 18, 2026 is exactly 26°C as reported by the Korea Meteorological Administration. Resolves NO if the high is any temperature other than 26°C.
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