Highest temperature in NYC on July 22?

Platform comparison

Market context

Polymarket is pricing the contract at **0% YES**, which means traders are currently assigning essentially no chance that LaGuardia’s recorded high on 22 July will land in the YES range once the market settles in USDC on Polygon. On Polymarket, the outcome is determined by the airport’s official Wunderground daily history entry, and the market only resolves after the first datapoint for the following date is published, with whole-degree Fahrenheit precision used for settlement.[1]

For context, New York City in July usually sits in the **high 20s to around 30°C** on average, with typical highs around 30°C, so the contract’s read today is less about whether it will be warm and more about whether the day reaches an extreme band that the market is currently discounting to zero.[2] That kind of pricing often reflects the narrowness of the settlement window and the fact that one airport station can diverge from broader city averages.

The main catalysts are straightforward: updated official observations at LaGuardia, any late-day temperature spike, and the fact that revisions remain relevant until the next day’s first datapoint appears.[1] Recent New York heat has shown that major East Coast records can be challenged in late summer pattern shifts, with July 2026 already producing a multi-city heat event that broke long-standing records.[3] Traders on the conditional-token market will usually watch whether synoptic heat builds into the 22nd or whether marine influence, cloud cover, or evening convection caps the airport high before the settlement cutoff.

Sources: 1 · 2 · 3

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

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 PolyGram. 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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.