Highest temperature in Wellington on August 19?

Platform comparison

Market context

On 19 August 2026, Wellington International Airport will record a daily maximum temperature in Celsius, which this market will settle against using Weather Underground's Daily Observations table rather than their summary high-low figures. The Polymarket contract is currently priced at 0% YES across all temperature bands, reflecting either extreme confidence in a specific range or minimal trading volume; USDC settlement on Polygon means any position requires gas fees and conditional token mechanics that lock capital until the resolution window closes at midday UTC on the settlement date.

Wellington's August climate sits firmly in the Southern Hemisphere winter, with historical daily maxima typically ranging from 11°C to 14°C during this month. The 0% probability across all ranges suggests traders expect temperatures to fall outside the offered brackets entirely, or that liquidity has not yet accumulated. Comparable August days at Wellington Airport over the past decade show occasional outliers—notably a 17.2°C maximum in August 2015—but sustained cold spells regularly produce highs below 10°C, particularly in the second half of the month when southern fronts intensify.

Traders monitoring this contract should track MetService forecasts released 7–10 days before 19 August, as these provide the most reliable guidance for New Zealand's weather patterns. The Southern Oscillation Index and sea surface temperatures around New Zealand will influence whether an anticyclone or low-pressure system dominates that week. Any unusual warming trend flagged by MetService in early August could shift market pricing materially, though the current zero probability suggests the market may be awaiting clearer atmospheric signals before capital deploys.

Methodology

We track Highest temperature in Wellington on August 19? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

UK Frequently Asked Questions

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.

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.

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%.