Shanghai May 31 High: 29°C Surges to Favorite

Shanghai’s weather market is moving fast. The 29°C outcome has surged to 53% implied probability in the last 24 hours, driven by a momentum composite that is hard to ignore: a 16% jump in the last hour and 25% over the past day, with a trend score of 75.96. The data doesn’t care about the politics of weather forecasting. Something in the meteorological picture shifted, and traders priced it immediately.

The market question asks: what is the highest temperature in Shanghai on May 31? The 29°C outcome sits at $0.53 YES and $0.47 NO. The market resolves at 12:00 UTC on May 31, 2026. Total volume stands at $70,220, with $58,847 traded in the last 24 hours alone.

How the Shanghai Temperature Contract Works

This contract resolves YES if Shanghai’s official peak temperature on May 31 lands exactly at 29°C. The resolution source is the market’s own data standard, drawing on official Shanghai meteorological reporting. Ten competing outcomes span 23°C or below up to 33°C or higher. A YES buyer on 29°C wins if the thermometer peaks at exactly that value.

• 29°C YES: $0.53 (53% implied probability)
• 30°C: competing outcome
• 28°C: competing outcome
• 31°C: competing outcome
• 32°C: competing outcome
• 33°C or higher: competing outcome
• 27°C and below: competing outcomes

A miss for 29°C means any other peak reading pays out zero on this contract. Shanghai’s late May climate places the city in a transitional window, where marine air from the East China Sea regularly competes with warmer continental air masses pushing in from the northwest. A 1°C shift in either direction is entirely within normal daily forecast error for this region and season. Traders betting against 29°C are not betting the temperature is extreme. They are betting on a different adjacent number.

Sponsored Partner

Momentum and Market Signals

The momentum composite here is unusually strong for a single-day weather market. A 16% hourly move combined with a 25% daily gain and a trend score of 75.96 suggests this is not random noise. The most likely driver is a specific forecast update from Shanghai Meteorological Bureau or a regional weather model run that pushed the probability mass toward 29°C and away from 28°C or 30°C.

Total volume of $70,220 is meaningful for a short-duration local weather contract, but it falls well below the $1 million threshold. That matters. Thin liquidity of $135,945 means a single large order can move price sharply. The $58,847 traded in the past 24 hours represents most of the lifetime volume, confirming this market activated late. Price swings are more volatile here than the percentage moves suggest.

• The 1h price change of +16% and 24h change of +25% together point to a late-breaking forecast signal, not gradual consensus building.
• Liquidity at $135,945 is real but concentrated. One informed trader with fresh model data can reprice this contract before resolution.
• Total volume below $1M means this price reflects a small number of active participants. Treat 53% as a directional lean, not a confident forecast.
• The trend score of 75.96 confirms sustained buying pressure, not a single spike that reversed.
• Related markets show elevated interest in global temperature events in 2026, suggesting some traders active here are cross-market participants watching broader climate signals.

Lines Analysis: What the Shanghai Data Is Saying

Here’s what the measurements are telling us. Late May in Shanghai historically produces peak temperatures in the 26°C to 32°C range. The 29°C outcome sits almost exactly in the middle of that distribution. That is not an accident. When forecast models converge on a mid-range value, traders recognize that 29°C carries the highest single-bin probability in a distribution spread across many adjacent outcomes. Even at 53%, one outcome winning against nine others is a strong signal in this format.

The risk for 29°C is real and specific. Shanghai Meteorological Bureau forecasts carry error bands. If a stronger sea breeze holds the city at 28°C, or a drier continental push brings it to 30°C, this contract pays nothing. The 30°C outcome is the most credible alternative. A small shift in the timing or intensity of the regional pressure system could push the peak reading one degree warmer. Traders holding adjacent outcomes are not wrong to stay in.

• Shanghai Meteorological Bureau’s next forecast update before May 31 resolution is the single most important signal to watch.
• Any regional pressure system shift toward the northwest would push peak temperature toward 30°C or 31°C and deflate the 29°C contract.
• A stronger-than-forecast marine influence from the East China Sea would cap temperatures at 28°C or below, also a loss for 29°C holders.
• The momentum surge in the last hour suggests a fresh model run or forecast update has already landed. If a second update confirms 29°C, expect price to hold or climb further.
• Resolution occurs at 12:00 UTC on May 31. Any late-day temperature reading after that window does not affect this contract.

The market is pricing uncertainty, not science. Total volume of $70,220 reflects a modest pool of participants making a directional call on a narrow meteorological outcome. The data currently favors 29°C, but the spread between YES and NO is close enough that a single forecast revision before resolution could flip the contract. Neither side has locked this in.

LINES VERDICT

NARROW LEAN TO YES

The momentum signal is real and the 29°C outcome sits at the center of Shanghai’s late May temperature distribution, giving it the highest single-bin probability against nine alternatives. But thin volume and a less-than-24-hour resolution window mean this market can reprice fast.

What the market says: At 53% implied probability, traders see 29°C as the most likely single outcome but not a lock. Volatility is high given the May 31, 12:00 UTC resolution and thin overall volume.

Key unknown: The next Shanghai Meteorological Bureau forecast update before resolution is the event that matters most. A one-degree revision in either direction would redistribute probability mass to 28°C or 30°C and sharply move this contract.

Scientific Context: Shanghai’s Late May Temperature Window

Shanghai in late May sits at the edge of the pre-plum-rain season. Average daily highs during this period run between 25°C and 30°C, with significant year-to-year variability driven by the East Asian monsoon onset timing. The 29°C to 30°C range is historically the most common outcome for peak daily temperature in this window. That historical base rate supports the market’s current lean, but single-day forecasts carry enough uncertainty that adjacent outcomes remain live.

What moves price before resolution: Any official forecast update from Shanghai’s meteorological authority, a regional model run showing a temperature shift, or observed morning temperature data on May 31 that allows traders to infer the day’s peak. The market resolves in hours, not days.

Highest temperature in Shanghai on May 31?

The contract resolves YES for 29°C if Shanghai’s official peak temperature on May 31 lands at exactly that reading. The resolution window closes at 12:00 UTC.

What does the NO side mean here?

Buying NO on 29°C means betting that Shanghai’s peak lands at any other temperature. Given nine alternative outcomes, NO at $0.47 reflects a reasonable spread of probability across adjacent readings like 28°C and 30°C.

What event would most move this contract?

A Shanghai Meteorological Bureau forecast revision pushing the predicted high to 28°C or 30°C would immediately reprice this market. Morning observed temperatures on May 31 would also signal where the day’s peak is heading.

When does this market resolve?

Resolution is set for May 31, 2026 at 12:00 UTC. That is a hard deadline. Temperature readings after that window do not affect the outcome.

Is the volume here reliable?

Total volume of $70,220 is below the $1 million threshold for high-confidence market pricing. Liquidity of $135,945 is real but thin. Price can shift sharply on a single informed trade before resolution.