Highest temperature in Wellington on August 15?

Platform comparison

Market context

On 15 August 2026, the highest temperature recorded at Wellington International Airport will fall into one of several defined ranges. The resolution hinges on the Daily Observations table in Weather Underground's historical data for that station, not the summary high-low figures displayed elsewhere on the platform—a distinction that matters when automated feeds pull from different endpoints. For programmatic traders, this means building a resolver that queries the correct WU API endpoint and parses the intraday observation records rather than relying on cached summary fields.

Wellington's August climate sits firmly in the Southern Hemisphere winter, with median daily highs around 12–13°C and extremes rarely exceeding 16°C. Historical August records at the airport show only occasional days above 15°C; the 0% crowd probability reflects this seasonal baseline. Comparable markets on winter temperature extremes in temperate zones typically see resolution in the lower ranges unless an unusual warm front or föhn-like wind event occurs. Traders should examine the last five years of August 15th observations specifically, as individual-day variance can be substantial despite stable monthly patterns.

The key catalyst is the Southern Oscillation Index and any forecast updates from MetService (New Zealand's national forecaster) in the week leading to mid-August 2026. Subtropical air masses occasionally push south into the Wellington region during winter, creating outlier warm days. A trader's edge lies in monitoring 10-day forecasts from late July onwards and cross-referencing them with upper-air pattern data; if a ridge of high pressure or northeasterly flow is predicted, the probability of a higher-range resolution increases materially. The settlement window closes at noon UTC on the 15th, requiring timezone-aware monitoring of the airport station's final observations.

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Kalshi Fees, which mirrors the Polymarket order book directly.

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

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Kalshi Fees trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.