This market settles on whether Seoul's lowest temperature on May 17, 2026, reaches exactly 21°C based on official Korean Meteorological Administration data. At 0% odds, traders are nearly certain the low will deviate from this precise threshold, reflecting the inherent difficulty of forecasting weather to exact degree-level accuracy. Mid-May Seoul typically experiences lows between 15–25°C, making 21°C meteorologically plausible but rarely exact. The overwhelming trader consensus toward NO implies either strong institutional weather model alignment on directional divergence or historical evidence that exact-degree temperature hits are exceptionally rare. The market expires in under 24 hours, leaving minimal time for new information to shift these extreme odds.
What factors could move this market?
Seoul's spring climate in mid-May represents a transitional zone between cool-season and warm-season patterns, with atmospheric conditions highly sensitive to upper-level wind patterns and the position of the North Pacific subtropical high-pressure system. The 0% odds on the 21°C low reflect traders' conviction that multiple physical mechanisms will push the actual low away from this target. Warming-side factors include solar radiation intensification as day length approaches 14+ hours, any high-pressure dome that suppresses cloud cover and enhances nighttime radiative retention, or an intruding warm air mass from the south. Cooling-side factors include clear-sky nocturnal radiative losses (if skies clear completely), upper-level cold air advection, or a transient low-pressure trough sweeping across. The specificity requirement—exact-degree precision—eliminates the probability mass that might exist for ranges like 20–22°C. Historically, exact-degree temperature forecasts are meteorologically improbable events; even advanced ensemble models show probability distributions spread across 2–3°C bands rather than single-degree concentrations. Korean Meteorological Administration station data from Seoul's numerous urban monitoring points would converge on a single official low value, but traders are pricing near-zero odds on that value matching 21°C specifically. The rapid market expiration (under 24 hours) combined with visible Seoul conditions on May 16 suggests any remaining information would only narrow the range further away from 21°C. Institutional participation in weather derivative markets likely reflects quantitative models that show very low probability mass at exactly 21°C.
What are traders watching for?
May 17 midnight Seoul local time: Korean Meteorological Administration releases official daily minimum temperature data determining final settlement
May 16 evening real-time conditions: Seoul station observations and institutional 24-hour forecasts confirm directional trend (warming or cooling)
Cloud cover and wind patterns May 16–17 morning: determine nocturnal radiative cooling magnitude and morning low final value
How does this market resolve?
Market resolves after the Korean Meteorological Administration records Seoul's lowest temperature on May 17, 2026. Settlement is YES only if the official low equals exactly 21°C; any other value resolves NO.
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