Chongqing, located in southwestern China at the confluence of the Yangtze and Jialing Rivers, experiences a humid subtropical climate with significant seasonal variation. In mid-May, the city transitions from late spring into early summer, with typical maximum temperatures ranging from 22–28°C. The market resolves based on whether the highest temperature recorded on May 18, 2026 reaches exactly 20°C—not above, not below, but precisely that figure. The 0% odds reflect trader consensus that this outcome is extremely unlikely. Given Chongqing's historical weather patterns and current seasonal trajectory, a maximum of exactly 20°C would represent either an unusually cool day or fall below typical expectations for mid-May. The specificity of the resolution criterion makes this a narrow outcome: traders are pricing in the likelihood that the day's high will either stay cooler than 20°C or exceed it. This is a short-duration forecast, settling in 2 days, so pricing reflects the most recent meteorological models and real-time weather conditions rather than long-term seasonal averages.
Deep dive — what moves this market
Chongqing's climate is shaped by its geography in the Sichuan Basin, a region bounded by high plateaus that trap warm, moist air masses. The city is known for extreme humidity and distinctive seasonal patterns. In May, Chongqing typically experiences maximum temperatures between 22–28°C, with occasional days in the low-to-mid 20s range during cooler spells or rainy periods. The market's resolution depends on the precise maximum temperature, not a range, which fundamentally shapes trading behavior. A reading of exactly 20°C would represent a notably cool day for mid-May in Chongqing—cool enough to suggest either an unusual weather system passing through or a persistent low-pressure pattern with above-average cloud cover and precipitation. This is achievable but statistically less likely than temperatures in the 23–27°C band that Chongqing typically experiences this time of year. For YES to occur, cooling mechanisms would need to align: sustained cloud cover, active monsoon circulation bringing moist southern air, or passage of a weak cold front. These conditions occur in May but are not the seasonal norm. Recent years have shown that Chongqing's May maxima tend to climb steadily as the month progresses, with mid-May often warmer than early May. For NO, either warmer-than-normal conditions (increasingly likely as solar insolation increases) or temperatures below 20°C would both count. The current 0% odds suggest traders see the probability of exactly 20°C as vanishingly small. This makes economic sense: weather outcomes typically follow continuous distributions, not discrete points. The odds imply confidence that May 18's high will fall into one of the tails—either cooler, in the rare 15–19°C band, or warmer, in the dominant 21–29°C band. Historical May data from Chongqing meteorological stations show wide variance in daily maxima, but the median clusters around 24–26°C. Days at exactly 20°C are relatively rare in the dataset. Recent years (2023–2025) have not shown a cooling trend; if anything, late-spring temperatures in Chongqing have been stable to slightly warmer. This makes a reading of 20°C an outlier outcome. The market's 2-day settlement window means traders are responding to short-range forecasts, where 48-hour models are more accurate than seasonal climatology. If official meteorological forecasts for May 18 predict temperatures in the 18–22°C range, YES odds would rise; if forecasts center on 24–27°C, the market will likely remain near 0%.
What traders watch for
Official Chongqing meteorological forecast for May 18; if models predict 18–22°C, YES odds may increase.
Monsoon activity and cloud cover patterns over southwestern China in the 48 hours before resolution.
Final 24-hour weather model updates; short-range forecasts are more reliable than seasonal norms.
May 17 actual maximum temperature; cooler days can indicate sustained low-pressure systems affecting May 18.
How does this market resolve?
The market resolves YES if Chongqing's highest temperature on May 18, 2026 reaches exactly 20°C according to official meteorological records. Any temperature other than 20°C results in NO.
Prediction markets aggregate trader expectations into real-time probability estimates. On Polymarket Trade, every market question resolves YES or NO based on a specific event outcome; traders buy shares of the side they believe will resolve positively. Prices range 0¢ (certain no) to 100¢ (certain yes) and naturally reflect the crowd-implied probability of YES. This page summarizes the market state for readers arriving from search; for live trading (place orders, see order book depth, execute a trade) open the full interactive page linked above.
