Highest temperature in Wellington on July 21?

Platform comparison

Market context

Wellington experiences its highest daily temperature on 21 July 2026 at the Wellington International Airport Station, with the market resolving to the Celsius range containing that peak. The crowd-implied probability of 0% YES suggests traders believe the event will not occur within the specified range, though the exact range defining “YES” is not stated in the prompt. Without the resolution threshold, the 0% figure reflects either a consensus that temperatures will fall outside the range or a lack of liquidity rather than a definitive meteorological forecast.

Historically, mid-July in Wellington sees average maximum temperatures between 10°C and 14°C, with extremes rarely exceeding 18°C. The last recorded high above 20°C in July occurred in 2019, when temperatures reached 21.3°C on 28 July, according to NIWA’s climate archive. Comparable cases show that July 21 has never recorded a temperature above 19°C in the past 30 years, making a high-temperature outcome in a narrow upper range statistically improbable unless an unusual heatwave develops.

Traders should monitor the Bureau of Meteorology’s daily synoptic charts and any sudden shifts in the Tasman Sea pressure systems, which can drive short-lived warm spells. A recent forecast from MetService (18 July 2026) noted stable cool conditions with no significant warming trend expected through late July, reinforcing the low probability of an extreme high. No official announcements or scheduled events are anticipated to alter regional weather patterns before the settlement window closes on 21 July 2026 at 12:00 UTC.

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 Kalshi vs Polymarket, which mirrors the Polymarket order book at 0% fees.

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

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Kalshi vs Polymarket. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

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.