Highest temperature in Wellington on July 21?

Platform comparison

Market context

On 21 July 2026, Wellington International Airport will record a daily maximum temperature, and this market resolves based on which range that figure falls into. The 0% crowd probability reflects the market's current state: no traders have positioned substantially on any temperature band, leaving the contract essentially unpriced. Settlement hinges on Wunderground's historical weather data for that specific station, with the resolution window closing at midday UTC on the day itself—a tight deadline that requires traders to commit before final conditions are known.

Wellington's winter climate in late July presents a constrained forecast space. Historical July maxima at the airport typically range between 10–14°C, with extremes rarely exceeding 16°C or falling below 8°C. The 2015 winter saw a peak of 15.2°C on 21 July; more commonly, the day records temperatures in the 11–13°C band. This historical clustering means the market's eventual resolution will likely fall within a narrow band, making precise range selection the key differentiator between profitable and underwater positions.

The primary catalyst is the Southern Hemisphere winter weather pattern developing in early July 2026. Traders should monitor MetService forecasts from mid-July onwards, particularly any anomalous warm fronts or high-pressure systems that could push Wellington above its seasonal norms. The Antarctic oscillation and Tasman Sea surface temperatures in early winter will influence whether July 21 tracks towards the warmer or cooler end of the historical distribution. Once the settlement window opens, real-time conditions at the airport become the only relevant input; the USDC-settled conditional tokens will reflect whatever Wunderground records as the day's high.

Methodology

This page reviews Highest temperature in Wellington on July 21? 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 PolyGram, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

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 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 fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

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

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.