Market prices an 80.5% chance of “Will the highest temperature in Shanghai be 28°C on August 9” — down 3.5 points in 24 hours
Original Polymarket title: “Will the highest temperature in Shanghai be 28°C on August 9?”
The move lacks solid trading support — treat the new probability with caution.
The pricing has weak support: healthy trading volume and market depth, an unusually wide spread. The probability moved another 11.5 points in the past hour — the market is still repricing.
How credible was the move?
Three separate questions — a move can be genuine while the latest price is still settling. Methodology →
Move validity
Is the move backed by real trading and depth?
The pricing has weak support: healthy trading volume and market depth, an unusually wide spread.
Consensus stability
Has the market settled at the new probability?
The probability moved another 11.5 points in the past hour — the market is still repricing.
Contract clarity
Will the rules resolve without ambiguity?
The resolution rules are relatively specific, with a named source and a defined deadline.
From the latest trade tape (most recent 200 prints) — a live activity sample, not a lifetime total.
What this market actually measures
This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section. This market will resolve to the temperature range that contains the highest temp…
This summary shows the opening of the venue's official rules. ProbCast has not yet generated an independent plain-English interpretation for this contract — review the full rules before relying on it.
View full official resolution rules
This market will resolve based on the highest temperature recorded in the 'Daily Observations' table on Weather Underground, not the figure displayed in the 'Day High & Low' summary section; in the event of any discrepancy between the two, the Daily Observations table shall be the primary resolution source not the Day High & Low section. This market will resolve to the temperature range that contains the highest temperature recorded at the Shanghai Pudong International Airport Station in degrees Celsius on 9 Aug '26. The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day for the Shanghai Pudong International Airport Station, available here: https://www.wunderground.com/history/daily/cn/shanghai/ZSPD. To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C. This market can not resolve until the first data point for the following date has been published on the resolution source. The resolution source for this market measures temperatures to whole degrees Celsius (eg, 9°C). Thus, this is the level of precision that will be used when resolving the market. Revisions to temperatures recorded within this market's timeframe will be considered until the first datapoint for the following date has been published, after which any alterations will not be considered.
Resolution source:
Why the odds moved
The probability fell 3.5 percentage points over the last 24 hours (84.0% → 80.5%).
No verified catalyst has been linked to this move yet. ProbCast does not attribute moves to news without evidence connecting the timing of a specific report to the repricing.
What could move this market next?
- The market's deadline arrivesAugust 9, 2026 at 8:00 AM ET
The contract must resolve based on what has happened by this date.
- Confirmation at the resolution source (wunderground.com)
The rules name this source as the basis for settlement.
Derived from the contract's own mechanics as of Aug 9, 3:27 AM ET. ProbCast does not list scheduled meetings, announcements, or data releases it cannot verify.
Advanced analysis (experimental)
Research signals — these models are still accumulating the history needed for full validation, and they can disagree with the headline read. Model confidence: low · expected error ±33 pts.
What's happening
The price is actively repricing on real volume. The number is still moving — don't treat the latest print as settled consensus yet.