Highest temperature in NYC on July 12?

Platform comparison

Market context

New York City is enduring a persistent heatwave, with LaGuardia Airport already recording a historic 94°F midnight temperature on 4 July 2026, setting the stage for extreme daytime highs on 12 July. The market in question resolves to the Fahrenheit range containing the peak temperature at LaGuardia on that date, sourced from Wunderground. While the current crowd-implied probability for any specific outcome sits at 0% YES on one platform, Polymarket shows a 55% implied probability for the 84–85°F range, with 82–83°F as the next closest at 27%[2]. This divergence highlights how platforms like Polymarket display decimal odds and implied probabilities differently from Kalshi’s binary contracts or Betfair’s odds-based liquidity, often leading to mispriced expectations across books.

Historical context frames the 0% probability as potentially anomalous; LaGuardia hit 104°F on 2 July 2026 during the same heatwave, surpassing its 1966 record of 101°F[9], and JFK reached 100°F earlier that week[6]. Such volatility suggests that assigning zero probability to any range ignores the station’s recent trajectory. Traders comparing platforms should note that Kalshi requires KYC and offers regulated binary contracts, whereas Polymarket operates with lower fees and no identity verification, affecting liquidity depth and price discovery on weather events like this.

Key catalysts include the National Weather Service’s daily maximum temperature forecasts for LGA and any updates from the U.S. Weather Prediction Center regarding sustained high-pressure systems over the Northeast[6]. With the settlement window ending 2026-07-12T12:00:00Z, traders must monitor real-time Wunderground data, as discrepancies between platforms’ resolution sources can create arbitrage opportunities. Recent reports confirm LaGuardia’s record-breaking midnight heat, reinforcing the likelihood of daytime highs exceeding 85°F[1][3].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We read Highest temperature in NYC on July 12? 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

What does Polymarket cost vs Kalshi?

Polymarket: 0% fees, only Polygon network costs (~$0.01/trade). Kalshi: up to 7% per trade plus spread. For high-frequency traders, Polymarket is dramatically cheaper.

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.

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.

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.

Which platform supports Klarna/SOFORT?

Directly: none. Polymarket accepts only USDC on Polygon. Kalshi Alternative UK offers a fiat on-ramp via Klarna or SOFORT (DE/AT/CH) and converts internally to USDC for the Polymarket order book. T+1 processing.