Highest temperature in Wellington on July 31?

Platform comparison

Market context

Wellington airport’s highest temperature on 31 July is being priced as an extreme downside event, with the contract currently on **0% YES** and the available forecasts pointing to a cool, unsettled day rather than anything near a high-range outcome. Temperatures.com has Friday’s Wellington forecast at a **53°F** high, or about **11.7°C**, with patchy rain and a 59% precipitation chance, while MetService’s Wellington outlook is even firmer around **8–9°C** for the capital, which is broadly consistent with winter norms rather than a surprise warm spike.[1][5]

Historically, late-July Wellington readings cluster in the low teens at best: AccuWeather’s July climatology shows a historical average high of **53–54°F** for 31 July, Weatherspark puts July daily highs around **53°F**, and Weather2Travel says Wellington usually reaches about **11°C** in July.[2][10][17] That makes the crowd’s 0% YES implied probability understandable if the market’s upper bands require an unusually warm airport reading. The key comparison across platforms is that sportsbook-style weather pages are all centred in the same single-digit-to-low-teens range, so there is no visible cross-market sign of a heat breakout that would lift the chance of a higher temperature bucket.[1][5][17]

For traders, the main catalysts are the final airport observations through the day, any late forecast shifts from MetService or Wunderground, and whether cloud cover, wind, or rain suppresses the afternoon high. NIWA’s seasonal outlook for May to July 2026 leaned towards temperatures near average or below average in much of the country, with occasional cold snaps possible, which supports a low-ceiling profile for this contract rather than a late-July warm anomaly.[19]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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.

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.

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.

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.