Highest temperature in Wellington on July 13?

Platform comparison

Market context

Wellington’s highest temperature on 13 July 2026 is being priced at a 0% implied probability for any outcome above the market’s baseline, yet long-term MetService data shows July highs typically cluster between 11–14°C with a mean near 12°C[1]. Historical records for Wellington confirm that 13°C is the modal July outcome, a pattern that has driven similar contracts to assign 97% probability to that exact figure in prior weeks[1]. The current 0% YES probability on the broader “highest temperature” contract likely reflects a misalignment in how the market interprets the resolution ranges rather than a genuine expectation of extreme cold, as comparable July 2 and July 7 contracts have consistently favoured 13°C or 14°C as the leading outcomes[2][9].

Traders should monitor real-time updates from Weather Underground, the designated resolution source, which publishes the daily maximum for Wellington Intl Airport Station in Celsius[1]. Any divergence between Wunderground’s live reading and the MetService forecast could trigger rapid odds shifts, especially as the settlement window closes at 12:00 UTC on 13 July[1]. Recent weather activity in New Zealand, including Auckland’s record-breaking July mean temperatures, suggests regional variability that may influence Wellington’s final reading, though Wellington itself has not matched Auckland’s extremes in the past decade[10]. With volume in similar contracts exceeding $47,000 and $37,000 changing hands in the last 24 hours alone, liquidity remains sufficient to absorb sudden price movements driven by model updates or data discrepancies[2].

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

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.

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'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.

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.