Lowest temperature in Tokyo on June 18?

Prediction market odds often diverge from traditional meteorological forecasts because they incorporate real-time trader positioning and uncertainty premiums. While weather analysts rely on numerical models and historical data to estimate the lowest temperature, this market reflects what participants are willing to stake on specific outcomes. Comparing the implied probability here to official forecasts from Japan Meteorological Agency or other analysts can reveal whether traders are pricing in more or less risk than experts currently project, highlighting areas of disagreement or confidence gaps.

On Polymarket, traders set the odds through an automated market maker mechanism where buying and selling pressure directly moves the price. On Polymarket, prices reflect that venue's order book, liquidity, and how traders price the outcome right now. Each share represents a claim on one outcome—either that the low will be 15°C or below, or above that threshold—and the price reflects the collective assessment of all active traders. As new information emerges or sentiment shifts, the probability updates continuously, allowing participants to enter or exit positions at any time before the market closes.

This market resolves around Jun 18, 2026, once the lowest temperature recorded in Tokyo on June 18 becomes verifiable from credible public sources. The outcome is determined by comparing the official low temperature for that day against the 15°C threshold specified in the market. Once the data is confirmed and published by recognized meteorological authorities, the market settles automatically, paying out traders who correctly predicted whether the temperature would fall below or remain above that level.

Weather model updates and seasonal forecasts are primary drivers of price movement in this market. Major atmospheric patterns—such as approaching cold fronts, high-pressure systems, or unusual jet-stream positioning—can shift trader expectations significantly. Additionally, historical temperature anomalies for mid-June in Tokyo, real-time atmospheric data releases, and any unusual weather alerts from meteorological agencies may prompt rapid repricing. As the date approaches, intraday weather refinements and overnight forecast adjustments typically increase volatility and trading volume.