Highest temperature in Shanghai on May 23?

Platform comparison

Active sub-markets

Market context

Shanghai's highest temperature on 23 May 2026 will be measured at Pudong International Airport Station and resolved via Wunderground historical data. The settlement window closes at midday UTC on that date, meaning traders must commit positions before the full daily maximum is certain. This timing constraint differs materially from Kalshi's US-focused weather markets, which often settle after official daily closes; Polymarket's earlier cutoff here creates asymmetric information risk that affects pricing across the range buckets.

Shanghai's May climate sits at the threshold between spring and early summer, with historical highs typically ranging from 28–32°C. The 0% crowd probability across all temperature ranges suggests either extreme confidence in a specific outcome or thin liquidity fragmenting positions. Comparable May 23 data from prior years shows variability: 2023 recorded 29.1°C, whilst 2022 peaked at 31.5°C. Decimal odds on Smarkets and Betfair would express these probabilities differently than Polymarket's binary format, potentially revealing where sophisticated traders see value. KYC requirements vary across platforms—Polymarket's lighter verification versus Kalshi's stricter US-resident checks—may influence which traders can access this market at all.

Catalysts include the China Meteorological Administration's seasonal forecasts, typically issued monthly, and any unusual atmospheric patterns developing in late April 2026. El Niño or La Niña conditions would shift May temperature expectations materially. Traders should monitor Shanghai's April temperatures as leading indicators; sustained warmth in spring months historically correlates with elevated May highs. Wunderground's data feed occasionally experiences delays in finalisation, though Shanghai's major airport station maintains reliable reporting standards.

Methodology

This page compares Highest temperature in Shanghai on May 23? 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 PolyGram, 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). PolyGram 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 PolyGram, 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.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does it cost to trade on PolyGram?

Zero. PolyGram 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.