Highest temperature in Wellington on July 28?

Platform comparison

Market context

Polymarket is pricing the **12°C** bucket as the clear favourite for the Wellington airport high on 28 July, with **11°C** next, so the market is already leaning towards a cool mid-winter reading rather than a mild outlier.[2] In practice, each outcome is traded in **USDC** on **Polygon**, and the correct temperature range settles through conditional tokens that pay out **$1** if that bracket matches the Wunderground airport reading and **$0** otherwise.[2]

That 0% implied chance for the YES side only makes sense if a trader is looking at an individual bracket outside the current consensus; the wider market view is not forecasting anything close to summer-like warmth. Wellington’s July climate is typically dominated by around **12°C** daytime highs, with frequent rain and brisk winds, which makes low-teens maximums the base case rather than a surprise.[3] NIWA’s July climate reporting also shows that New Zealand’s winter extremes are usually modest even in a relatively warm month, with the national monthly high last July reaching **22.7°C** well away from Wellington’s normal range.[1]

The main catalysts are local weather system shifts over the next 24 hours: a northerly wind change, a passing front, or clearer-than-expected skies could move the airport’s high by a degree or two and matter for adjacent brackets. Traders should watch the Wunderground Wellington Intl Airport Station page for the final daily maximum, because the market resolves on that source rather than on general city forecasts.[2] As the settlement window closes on 28 July at **12:00:00Z**, late-session liquidity can still reprice if overnight forecast runs change the expected midday temperature path.[2]

Sources: 1 · 2 · 3

Methodology

We track Highest temperature in Wellington on July 28? 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

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 UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

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.