Highest temperature in NYC on July 6?

Platform comparison

Market context

A severe heatwave is currently gripping New York City, with LaGuardia Airport hitting 104°F on 2 July 2026, surpassing its 1966 daily high of 101°F[3]. This extreme event frames the current 0% crowd-implied probability for a specific temperature range on 6 July, suggesting traders view the market as settled or the target range as unattainable given the recent volatility. Historical data shows LaGuardia recorded a record-breaking 94°F at midnight on 4 July, breaking the 2013 record of 93°F[1], indicating that night-time temperatures remain unusually elevated during this spell.

Traders should monitor Delta Air Lines’ weather alerts for LGA, as operational constraints compounded by heat may disrupt travel schedules and influence local temperature readings[9]. The resolution depends entirely on Wunderground’s highest daily reading for LaGuardia, making the timing of peak heat critical. While Robinhood offers a similar climate event for the daily low on 6 July[6], platforms diverge significantly: Polymarket uses implied probability with lower fees and no KYC, whereas Kalshi requires identity verification and trades decimal odds with higher regulatory oversight. Betfair and Smarkets further differ by offering decimal odds with distinct fee structures, creating arbitrage opportunities where implied probabilities do not align across books.

The divergence in market mechanics means a 0% probability on one platform may not reflect identical risk on another, especially when fee structures and liquidity vary. Kalshi’s strict KYC reach limits participation compared to Polymarket’s open access, while Betfair’s commission model alters net returns compared to Smarkets’ flat fee. These structural differences mean traders must assess not just the weather event, but how each book’s pricing model interprets the same underlying data. The heatwave’s persistence suggests the 6 July peak could still breach previous highs, making the 0% figure a potential mispricing if the range is not definitively closed.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We read Highest temperature in NYC on July 6? from four platform perspectives: Polymarket (on-chain CLOB), Kalshi (CFTC-regulated exchange), Betfair Exchange (sports book exchange), Smarkets (peer-to-peer betting exchange). Polymarket's live mid is the canonical probability; the side-by-side columns benchmark fees, KYC, settlement currency and deposit rails so you can choose the venue that fits your jurisdiction and trade size.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

Which platform has the deepest liquidity?

Polymarket — by a wide margin. Top markets reach $50-500M volume, Kalshi ~$200M cumulative, Betfair similar. Deeper liquidity means your trade moves the quote less.

Is Betfair a Polymarket alternative?

Only partially. Betfair Exchange is UK-focused with a sports-betting emphasis; they have politics markets but with thinner liquidity than Polymarket. Settlement in GBP/EUR, 2-5% commission on winnings.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Which platform is accessible globally?

Polymarket is geo-blocked in the US/UK/EU. Kalshi is US-only. Betfair and Smarkets are UK-restricted. Polymarket Alternative has a different geo footprint and routes to Polymarket's order book at 0% fees.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.