Highest temperature in Wellington on July 21?

Platform comparison

Market context

Wellington’s highest temperature on 21 July 2026 at the International Airport Station will determine this weather contract’s outcome, with the crowd currently assigning zero per cent probability to any “YES” resolution. Historical July records for Wellington show maximums rarely exceed 15°C, with the all‑time July high at NZWN sitting near 19°C in 1995; such cool, maritime conditions make a significant heat spike on this specific date statistically improbable under current climate norms.

The zero per cent implied probability aligns closely with analyst consensus that mid‑winter Wellington rarely experiences temperatures above 16°C, and diverges sharply from any sportsbook line that might offer odds on extreme heat events in other regions—though no direct sportsbook equivalent exists for this localised date. Traders should monitor the Bureau of Meteorology’s daily high‑pressure forecasts for the Tasman Sea and any sudden shifts in the Southern Oscillation Index, as a rapid drop in pressure could introduce unseasonal warmth; the latest MetService update notes stable southerly flows dominating the region through late July, reinforcing the baseline expectation of cool conditions.

Given the settlement window closes at 12:00 UTC on 21 July 2026 and the resolution source is Wunderground’s NZWN daily high, the market’s current pricing reflects a near‑certainty that temperatures will fall within the lower Celsius ranges, leaving little room for upside surprise unless an unexpected atmospheric anomaly occurs.

Methodology

We track Highest temperature in Wellington on July 21? 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

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

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 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 Best Prediction Markets 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.