Highest temperature in Shanghai on July 31?

Platform comparison

Market context

Shanghai’s airport weather reading for 31 July will be set by the day’s highest observed temperature at Pudong, so the relevant real-world event is a single-station heat reading rather than a citywide average. July is normally Shanghai’s hottest month, with typical highs around 31–32°C, but the city has a history of much sharper spikes when the subtropical high strengthens and heatwaves build over eastern China.[3][4][9]

That historical backdrop helps explain why a 0% crowd-implied chance on the top end should be treated cautiously: Shanghai has repeatedly printed 37°C-plus readings in late July and early August, and the city’s all-time extreme stands at 40.9°C at Xujiahui, reached in July 2017 and matched in 2022.[2][17] Comparable late-July heat events show that the distribution is skewed towards uncomfortable but not always record-level heat, so traders should focus on whether today develops into a sustained heatwave rather than a brief warm spell.[10][17]

The main catalyst is the local forecast and any official heat alerts from the Shanghai weather authorities, with the market leaning on whether a subtropical high-pressure setup keeps skies hot, humid and largely rain-free through the daytime window before the settlement cut-off.[2][16] A recent city update also notes that Shanghai’s record-hot spell last year was tied to the subtropical high, underscoring the same mechanism traders are watching now.[2] The key dependency is the midday-to-afternoon high at Pudong Airport, since that is the number Wunderground will use for resolution.[5]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Political prediction markets differ structurally from sports betting: thinner liquidity, longer settlement windows, higher sensitivity to single news events. This page shows the live Polymarket quote for Highest temperature in Shanghai on July 31? plus platform attributes for the three reference venues, so you can see at a glance where the deepest market for this question sits.

Resolution & payout

Political markets typically settle on official candidate or agency confirmation. Polymarket uses UMA Optimistic Oracle: a proposer posts the outcome with a bond, the two-hour window opens, then the smart contract pays USDC.

Kalshi settles USD via CFTC clearinghouse, with clearly defined resolution sources (e.g. AP race calls for elections). Betfair settles after the official outcome is registered with the league or agency. Manifold is play-money.

FAQ

What resolution source is used for elections?

Polymarket defines the source per contract — usually Associated Press (AP Race Call), Reuters or the official electoral commission. The source is stated in contract details before the market opens.

Can prediction markets influence election outcomes?

Markets reflect expectations rather than create them. Studies show public-facing markets can anchor expectations, but don't influence the underlying outcome. Political markets are information, not advocacy.

How fast do political markets react to news?

High-liquidity markets move within seconds to minutes. A Trump tweet on the economy can shift the "Trump 2024" market 2-5 points before mainstream media has written anything.

Are political prediction markets legal in my country?

It varies. They sit in legal gray areas in most jurisdictions. Polymarket is geo-blocked from US/UK/EU; some broker frontends have a different geo footprint. Trade only with capital you can afford to lose, and only if you understand the legal status in your jurisdiction.

Why do Polymarket and Kalshi differ on elections?

Kalshi must follow CFTC compliance — strict definitions, clear resolution sources, US citizens only with KYC. Polymarket operates globally without CFTC oversight — deeper liquidity, but also higher regulatory risk.