Highest temperature in NYC on July 5?

Platform comparison

Market context

The underlying event is the peak Fahrenheit temperature recorded at LaGuardia Airport on 5 July 2026, a date that historically sits within New York’s most volatile summer heat window. Current crowd-implied probability of 0% for the highest range suggests the market expects temperatures to remain well below extreme thresholds, yet this stance contradicts recent precedent where LaGuardia hit 102°F on a Thursday in July, with midnight temperatures reaching 94°F—breaking the 2013 record of 93°F[1][3]. This history proves that heatwaves in NYC can persist into the night, and July 5 specifically saw a record high of 100°F in 1999, indicating that 84–85°F is not a guaranteed ceiling[7].

Traders approaching this market programmatically should monitor real-time Wunderground feeds for LaGuardia and cross-reference with NWS climate normals, which list a maximum record of 100°F for this date[5]. A key catalyst is the National Weather Service’s forecast for Central Park, which currently assigns 34.5% odds to the 84–85°F range, though thin volume of $5,602 limits confidence in that signal[2]. Recent reports confirm LaGuardia and Newark both reached 104°F in July 2026, with heat indexes peaking as dew points climbed back into the 70s, suggesting that humidity and sustained high pressure could drive temperatures higher than the market anticipates[6]. Any sudden shift in dew point or cloud cover before settlement will be critical for conditional order execution.

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

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

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 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 Polymarket Bot UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.