Will Seoul's highest temperature on May 18 be exactly 21°C? Trading at 1% YES. Traders view this precise daily outcome as unlikely given Seoul's typical spring weather patterns.
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Seoul in mid-May typically experiences daytime highs ranging from 20 to 27°C, depending on synoptic weather patterns and frontal systems moving across the Korean Peninsula. A daily high temperature of exactly 21°C represents a relatively cool outcome for Seoul at this time of year, when spring warming pushes toward early summer conditions. The market prices this precise outcome at just 1% YES, reflecting strong trader conviction that Seoul's May 18 high will exceed 21°C. The resolving criteria are unambiguous: the highest temperature (in whole degrees Celsius) recorded in Seoul on May 18, 2026, compared against the exact 21°C threshold. This type of granular weather market attracts both amateur weather enthusiasts and professional meteorological traders testing forecast accuracy and climate patterns. The 1% odds imply traders collectively expect Seoul to be warmer—either a clear sunny day with robust insolation or an unseasonably warm pressure pattern for mid-May. Historical Seoul May weather and current seasonal anomalies likely inform this pricing. The 24-hour volume of $2,939 indicates moderate trader engagement despite the low YES odds and short two-day time horizon.
Seoul's climate in mid-May sits at a natural inflection point between late spring and early summer. Historically, May 18 highs in Seoul range from 18°C to 29°C across four decades of meteorological records. The Korean Peninsula experiences increasingly volatile weather during May due to competing air masses: the remnants of cooler continental polar air from Mongolia and Siberia clash with warm tropical maritime air advancing northward from the Pacific. The exact temperature threshold of 21°C is remarkably narrow and requires a specific weather regime to materialize. Factors pushing the outcome toward YES are limited but plausible. A weak upper-level low-pressure system stalled over Korea, combined with persistent cloud cover and cool northerly winds, could suppress the daily high to only 21°C. Recent May patterns from 2019 and 2020 show occasional days where Seoul recorded highs near 20–22°C despite being late spring. A delayed warm surge or a mid-latitude cyclone moving through could prevent typical May heating. Such days are notable but historically uncommon by mid-May. Factors pushing toward NO (higher temperatures) dominate seasonal climatology. Seoul's average high in mid-May is approximately 24°C, with typical maximums clustering around 24–26°C. Recent climate trends show spring warming accelerating—Seoul's May temperatures have drifted warmer over the past two decades. A high-pressure ridge positioned over Korea, clear skies, and southerly winds could easily push the high to 26–28°C. The current 1% YES odds reflect this overwhelming statistical improbability: hitting exactly 21°C is an outlier requiring coolness that May rarely delivers to Seoul. Analogous low-probability weather markets in past years reveal trader behavior: outcomes priced below 2% typically occur in fewer than 1% of resolved cases. Seoul's seasonal pattern strongly disfavors this threshold. The 1% pricing also reflects the short two-day window—no material new meteorological forecasts will likely shift the consensus that Seoul will be warmer. The $7,602 total liquidity shows this market remains relatively illiquid, typical for hyper-specific weather contracts. Traders pricing YES at 1% are essentially betting on a surprise cool snap.
The market resolves YES if Seoul's highest recorded temperature on May 18, 2026 equals exactly 21°C (whole degrees Celsius) as reported by the Korea Meteorological Administration. It resolves NO if the high is any temperature other than 21°C.
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