Highest temperature in NYC on July 9?

Platform comparison

Market context

The real-world event hinges on the peak Fahrenheit reading at LaGuardia Airport on 9 July 2026, a date currently marked by a crowd-implied probability of zero per cent for any specific outcome. This near-absence of conviction reflects the volatile nature of the July 2026 heatwave, which has already shattered historical benchmarks across the East Coast. Just days prior, LaGuardia recorded 104°F on 3 July, eclipsing the 1966 record of 101°F by three degrees and triggering unprecedented conditions that killed 29 people in New Jersey[1]. Such extreme volatility suggests that while the market currently shows no confidence, the atmospheric potential for a record-breaking high remains substantial, framing the zero probability not as a certainty of coolness but as a lack of directional clarity in a rapidly shifting climate system.

A power-user evaluating this tooling would approach the market programmatically, monitoring real-time Wunderground feeds for LaGuardia (KLGA) rather than relying on static forecasts. The critical catalyst to watch is the persistence of the current heat dome, which has already pushed midnight temperatures to 94°F, breaking the 2013 record of 93°F and proving that heat lingers dangerously into the night[4]. Traders must track the National Weather Service time-series data for KLGA to detect any sudden shifts in wind speed or precipitation that could disrupt the thermal accumulation[8]. Recent reports confirm that the July 2026 heatwave simultaneously broke records standing for up to 154 years across a 500-mile corridor, indicating that the atmospheric pressure system is exceptionally robust and unlikely to dissipate without a significant weather event[1].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in NYC on July 9? 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

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

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 Polymarket Bot UK. 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.

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 Polymarket Bot UK 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.