Highest temperature in Wellington on July 20?

Platform comparison

Market context

The market hinges on the peak temperature recorded at Wellington International Airport on 20 July 2026, a date deep in the Southern Hemisphere’s winter. With the crowd-implied probability for any specific outcome sitting at 0% YES, the data suggests the current pricing model has either failed to load valid ranges or the market remains entirely unliquid despite the settlement window closing in hours.

Historically, mid-July in Wellington sees maximum temperatures rarely exceeding 14°C, with the all-time record for the month hovering near 19°C. A 0% probability across all ranges is statistically anomalous for a weather event with such a tight historical distribution, indicating a likely technical glitch in the resolution engine rather than a genuine belief that no temperature will occur. Programmatic traders should script a check against the Wunderground API endpoint immediately; if the history page returns null or an error, the market is effectively broken and requires manual intervention before the 12:00 UTC deadline.

No external catalysts like announcements or schedules influence this outcome, as the variable is purely meteorological and dependent on atmospheric conditions on that specific day. The only dependency is the integrity of the Wunderground data feed, which serves as the sole resolution source. Traders evaluating tooling should note that conditional orders based on live temperature feeds will fail if the API does not update, making a direct scrape of the daily history page the only reliable utility for verifying the final settlement value before the clock expires.

Methodology

This page reviews Highest temperature in Wellington on July 20? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Kalshi Fees, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Kalshi 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'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 Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

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.