Highest temperature in NYC on July 8?

Platform comparison

Market context

The underlying event is a straightforward measurement: the highest temperature recorded at LaGuardia Airport on 8 July 2026, resolved in degrees Fahrenheit via Wunderground. This market currently shows a 0% implied probability for the "YES" outcome, suggesting the crowd expects the temperature to fall outside the specific range being bet on, likely due to recent extreme heat pushing values higher than the threshold.

Historical data frames this probability starkly, as LaGuardia has recently shattered records with a 102°F peak on 4 July 2026 and a 94°F midnight reading, the highest ever recorded at the station[1][2]. The station’s all-time high is 102°F from September 1953, but it recently hit 101°F on 3 July 2026, indicating a persistent heatwave that makes lower temperature ranges improbable[10]. Programmatic traders would model this by weighting the last three days’ 100°F+ readings against the July 2026 forecast range of 73°F to 91°F, noting the current anomaly exceeds the average significantly[3].

Traders must monitor the immediate weather schedule for LaGuardia, specifically the National Weather Service climate summaries which recently flagged a record year maximum of 99°F[5]. The catalyst is the continuation of the East Coast heatwave, which has already driven temperatures to 101°F, a level that would resolve any bet on a lower range as a loss[2]. A conditional order strategy would likely short the lower temperature brackets, as the current trend shows no immediate cooling, with the heat lingering well into the night and breaking daily high records[1]. The settlement depends entirely on the Wunderground daily max, which has consistently exceeded 100°F in this heat event, making the current 0% probability a rational reflection of the data.

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

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 Fees. 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.

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 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.