Highest temperature in Wellington on August 18?

Platform comparison

Market context

Wellington's maximum temperature on 18 August 2026 will be recorded at the airport weather station and resolved against the Daily Observations table on Weather Underground. The crowd currently implies 0% probability across all temperature ranges, suggesting either extreme confidence in a particular outcome or minimal trading activity. August is Wellington's winter month, with historical daily maxima typically ranging between 10–14°C, though the specific range buckets for this market will determine where value emerges once trading begins.

Wellington's August temperatures show modest year-to-year variation. Over the past decade, 18 August highs have ranged from 8°C to 16°C, with most years clustering around 11–13°C. The 0% crowd probability likely reflects either a technical issue with market initialisation or traders awaiting clearer range definitions. Historical precedent suggests the most probable outcome sits in the 11–14°C band, though unusually mild or cold systems can shift this considerably. The resolution methodology—prioritising the Daily Observations table over summary figures—matters for edge cases where station readings diverge slightly.

Traders should monitor MetService forecasts and NIWA outlooks as August 2026 approaches, particularly any signals of anomalous weather patterns. Southern Hemisphere winter patterns, including potential polar incursions or blocking highs, could push temperatures outside the typical range. The settlement window closes at noon UTC on 18 August, meaning New Zealand's morning observations will determine the outcome. Early market movement will likely cluster around historical norms once liquidity arrives, but any seasonal forecast indicating departure from the 11–14°C band could create genuine contrarian value.

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 Who Will Win, 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.

UK Frequently Asked Questions

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 Who Will Win. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.