Highest temperature in Wellington on August 21?

Platform comparison

Market context

Wellington's maximum temperature on 21 August 2026 will be measured at the airport weather station and resolved against the Daily Observations table on Weather Underground. The settlement window closes at midday UTC on that date, meaning the highest temperature reading recorded up to that point determines the outcome. August falls within Wellington's late winter period, when daily highs typically range between 11–13°C, though conditions can vary significantly depending on frontal systems moving across the lower North Island.

Historical August temperatures at Wellington Airport show considerable variability year to year. Over the past decade, maximum temperatures in August have ranged from around 8°C during colder spells to occasional peaks near 16–17°C when warm northerly flows precede cold fronts. The 0% crowd probability suggests traders are pricing in an expectation that the market's temperature thresholds sit above what August meteorology typically delivers. The resolution methodology—using the Daily Observations table rather than summary figures—introduces a technical dependency that could affect outcomes if discrepancies arise between different Weather Underground data feeds.

Traders should monitor MetService forecasts and NIWA seasonal outlooks as August 2026 approaches, particularly any signals about whether the month will track warmer or cooler than the 30-year normal. The specific temperature bands offered in this market will determine whether the 0% assessment reflects genuinely unlikely conditions or simply reflects current crowd sentiment before forecasting data becomes available. Weather station maintenance or data recording issues at Wellington Airport could also influence resolution, though such occurrences are rare.

Methodology

This page tracks Highest temperature in Wellington on August 21? across four political prediction venues. Live odds come from the Polymarket order book (the deepest political prediction-market book). Kalshi is the CFTC-regulated US alternative, Betfair the established UK sports-exchange with politics markets, Manifold the open play-money variant. For users geo-blocked from Polymarket directly, brokers like Trump Prediction provide a 0%-fee route into the same order book.

Resolution & payout

Political markets typically settle on official candidate or agency confirmation. Polymarket uses UMA Optimistic Oracle: a proposer posts the outcome with a bond, the two-hour window opens, then the smart contract pays USDC.

Kalshi settles USD via CFTC clearinghouse, with clearly defined resolution sources (e.g. AP race calls for elections). Betfair settles after the official outcome is registered with the league or agency. Manifold is play-money.

UK Frequently Asked Questions

How accurate are political prediction markets?

Historically more accurate than polls. Polymarket's Brier score on US 2024 elections was ~0.11 — better than 538 (~0.14) and every mainstream poll. Markets aggregate information with real skin in the game.

What resolution source is used for elections?

Polymarket defines the source per contract — usually Associated Press (AP Race Call), Reuters or the official electoral commission. The source is stated in contract details before the market opens.

Which platform has the deepest political liquidity?

Polymarket — by far. US 2024 presidential volume was ~$3.5B vs Kalshi (~$200M) and Betfair (~$120M). Where Polymarket is geo-blocked, brokers like Trump Prediction route into the same order book at 0% fees.

Why do Polymarket and Kalshi differ on elections?

Kalshi must follow CFTC compliance — strict definitions, clear resolution sources, US citizens only with KYC. Polymarket operates globally without CFTC oversight — deeper liquidity, but also higher regulatory risk.

Are UK election prediction markets available from the UK?

Yes. Betfair Exchange and Smarkets offer UKGC-regulated UK election markets (seat counts, party share, constituency results). Polymarket also lists UK election contracts with deeper global liquidity. Betfair winnings are typically tax-free for UK individuals; Polymarket profits are subject to HMRC CGT.