Highest temperature in Shanghai on June 20?

Platform comparison

Active sub-markets

Market context

Shanghai’s highest reading on 20 June will depend on the afternoon peak at Pudong International Airport, where June normals are already warm and humid. WeatherSpark says average daily highs at Shanghai Pudong International Airport rise through the month and typically sit around 77°F to 83°F in June, with extremes rarely above 92°F, which frames this as a fairly ordinary summer-heat event rather than a tail-risk heatwave market.[1] AccuWeather’s June outlook for the airport also points to highs in the mid-20s to high-20s Celsius, reinforcing that the settlement range is usually decided by whether the day lands near the lower or upper end of the seasonal band.[2]

For historical comparison, traders should treat a 0% implied YES as more a platform-pricing artefact than a statement that the event is impossible. On Kalshi-style contracts, the quoted probability is usually the cleanest way to read the market; on Betfair, Smarkets and many betting exchanges, the same view is often expressed through decimal odds, and the effective price can be distorted by commission and spread rather than just raw probability. That matters here because a weather settlement tied to a single station on a single day is sensitive to local cloud cover, sea breeze, and rainfall, yet still anchored by a well-known June climate profile rather than an exotic threshold event.[1][4]

The main catalysts are the short-range forecast for Shanghai Pudong International Airport, any late shift in rain bands, and whether daytime heating is limited by cloud or precipitation before the 12:00 UTC settlement cut-off. Weather-forecast models for the airport can change materially over 48–72 hours, so traders will watch the final update cycle more than any longer-range seasonal view.[3][5] Platform access also matters: Polymarket and Kalshi typically use US-style market interfaces, while Betfair and Smarkets expose odds in decimal terms and may impose different KYC and jurisdictional restrictions, which affects who can actually price this market and how quickly new information is reflected.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares Highest temperature in Shanghai on June 20? specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. Live odds come from the Polymarket order book; the other venues' contract details are maintained manually because their APIs aren't directly comparable. Every CTA routes to Kalshi Alternative UK, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Settlement is the biggest difference between the four platforms: Polymarket on-chain in USDC (instant), Kalshi USD via CFTC (T+1), Betfair and Smarkets in local currency via bank withdrawal (T+1 to T+3). Kalshi Alternative UK routes every trade directly into Polymarket's on-chain settlement, which is why payouts land fastest.

FAQ

Where can I trade this market with the lowest fees?

On Kalshi Alternative UK, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What does it cost to trade on Kalshi Alternative UK?

Zero. Kalshi Alternative UK routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.