Highest temperature in NYC on July 22?

Platform comparison

Market context

The temperature recorded at LaGuardia Airport on 22 July will decide this market, and the present 0% yes price leaves it trading far below the sort of outcome implied by recent forecast guidance. Polymarket’s own market note points to a likely NYC maximum in the **83–87°F** range, with partial cloud cover and a possible seabreeze capping the peak; that is broadly consistent with a summer climatology near the low-80s, but not with a contract priced as if a qualifying range is impossible.[1]

That gap matters because comparable mid-July setups in New York tend to settle in the mid-80s unless a stronger heat ridge or unusual cloud/rain pattern intervenes. The same market note flags 84–87°F bins as the centre of the probability mass, while readings above 90°F or below 80°F are treated as tail outcomes.[1] In other words, the cross-platform comparison is stark: sportsbook-style pricing is effectively absent here, prediction-market pricing is pinned to zero, and the analyst framing embedded in the contract description still leans towards a fairly ordinary warm-day outcome rather than an extreme.

For traders, the main catalysts are the final airport observation, any late-afternoon convection, and whether the sea breeze reaches LaGuardia before the day’s high is locked in. The market cannot resolve until the first data point for the following date appears on the source, so there can be a lag between the actual weather and settlement timing.[1] Any meaningful deviation from the 83–87°F band would most likely come from cloud cover, thunderstorm timing, or a stronger-onshore flow than forecast.[1]

Sources: 1 · 2 · 3 · 4

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

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.

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.

Do I need to KYC for this market?

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

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.