Seoul June 20 Low Temp: Will It Hit Twenty-One Celsius?

Seoul’s overnight temperature on June 20 has traders split almost down the middle. The 21°C outcome carries a 55% implied probability, but a sharp intraday swing tells a more unsettled story. Here’s what the measurements are telling us: this market repriced nearly 20% in a single hour, which means new weather data or model updates are driving conviction faster than the probability suggests.

The market question asks for the lowest temperature recorded in Seoul on June 20. The YES outcome resolves at exactly 21°C. YES trades at 0.55 and NO at 0.45. The market closes June 20 at 12:00 UTC. Total volume stands at $11,327, with $8,014 of that changing hands in the last 24 hours.

How the Seoul Temperature Contract Works

YES pays out if Seoul’s official minimum temperature on June 20 lands precisely at 21°C. NO covers every other outcome, including 20°C, 22°C, and all higher or lower brackets. The resolution source is the market operator’s designated weather data, which draws on official Seoul meteorological readings. With eleven discrete outcome buckets, this is not a binary directional bet. It is a precision call on a single degree.

• YES (21°C) is priced at 0.55, implying a 55% probability.
• NO (all other outcomes combined) is priced at 0.45, implying a 45% probability.

The NO position wins if Seoul’s low drifts even one degree in either direction. Late-June Seoul nights typically sit in the 20°C to 24°C range as the pre-monsoon humidity builds. A cooler northerly push would favor the 19°C or 20°C buckets. A warm, humid night would shift weight toward 22°C and above. The 21°C outcome requires a very specific atmospheric setup to hold all night.

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Momentum and Market Signals

The combined momentum signal here is aggressive. The 1-hour price change of +19.5%, a 24-hour gain of +16.0%, and a trend score of 78.31 all point in the same direction. That kind of single-session move in a weather micromarket almost always traces back to a forecast model update or a fresh synoptic pattern emerging in the 24- to 48-hour window before resolution.

Total volume of $11,327 is thin. The $8,014 transacted in the last 24 hours represents the majority of all activity, and liquidity sits at $18,120. This is a low-volume market, which means a single large order can reprice the contract sharply. The market is pricing uncertainty, not science.

• The 1-hour and 24-hour price gains (+19.5% and +16.0%) suggest a recent forecast shift toward the 21°C range.
• Total volume below $1M means price can move sharply on any new weather model output or observation update.
• Liquidity at $18,120 is thin but sufficient to absorb moderate trades without severe slippage.
• Trader sentiment is split: 55% YES versus 45% NO, with no dominant directional lean among participants.
• The trend score of 78.31 reflects strong short-term momentum but does not confirm a sustained directional consensus.

Lines Analysis: Seoul’s June Low and the One-Degree Problem

The case for 21°C rests on Seoul’s typical late-June climatology. Seoul sits in a transition window between dry spring conditions and the summer monsoon. Nighttime lows during this period frequently cluster in the 20°C to 22°C band. A moderate southwesterly flow with partial cloud cover is the setup most consistent with a 21°C floor. The recent momentum surge suggests the latest model runs moved in that direction, which is why the YES price jumped.

What makes the NO position real is the precision requirement. Seoul’s actual low does not need to miss by much. A monsoon advance arriving even a day early would bring humidity and cloud cover that keeps the low at 23°C or 24°C. A brief drainage wind from the north would push the low toward 19°C or 20°C. The 21°C outcome wins only if the overnight boundary layer holds within a one-degree corridor for the full measurement period.

• Korea Meteorological Administration forecast updates in the next 12 hours will be the single most important data input before resolution.
• A shift in the monsoon front timing toward Seoul before June 20 would push overnight lows higher, favoring buckets above 22°C.
• A clearer-than-expected sky with reduced humidity overnight would favor cooler outcomes in the 19°C to 20°C range.
• Any new weather model consensus (GFS, ECMWF) aligning on a different temperature range would reprice this market immediately given thin liquidity.

Total volume of $11,327 is light, and the sharp intraday moves confirm that a small number of traders with access to updated forecast data are driving price discovery. The data right now favors 21°C at 55%, but the precision of the threshold means this market will remain volatile through the resolution window.

LINES VERDICT

NARROW EDGE FOR TWENTY-ONE CELSIUS

Seoul’s late-June climatology supports the 21°C outcome, and the momentum surge tracks a recent forecast model shift in that direction. But this is a one-degree precision market in a volatile meteorological window, and thin liquidity amplifies every new data point.

What the market says: A 55% implied probability is a coin flip with a slight lean. With resolution in less than 24 hours, any forecast model update or observed pressure change can move this contract by 10 to 20 percentage points almost instantly.

Key unknown: The Korea Meteorological Administration’s next official forecast update and any shift in the low-level jet stream position over the Korean Peninsula before midnight June 19 local time are the data points that will determine whether 21°C holds as the consensus outcome.