Highest temperature in NYC on August 3?

Platform comparison

Market context

A single hot afternoon at LaGuardia Airport will decide this contract, and the current market is not pricing in a blowout: Polymarket has the highest-probability band at **82–83°F** with **35%**, just ahead of **84–85°F** at **33%**, while Robinhood’s related contract is centred on **81°F** at **68¢**, which points to a slightly cooler consensus on the same New York City high-temperature theme.[1][4] That gap matters because the market resolves to the *highest temperature actually recorded* at LaGuardia, not a citywide average, so a brief spike in the afternoon can push the outcome up a band even if the day mostly sits in the low 80s.[1]

Recent guidance has framed this as a tight, low-volatility call rather than a wide-open heat play. Polymarket’s own market text says the latest National Weather Service and model guidance pointed to a daytime high of **82–85°F**, with the two leading outcomes nearly tied, while other forecast aggregators for New York City have also clustered around the upper 20s to low 30s Celsius, consistent with an 80s Fahrenheit finish.[1][3][7] For comparison, New York has recently seen hotter summer days, including a **83°F** maximum reported for 3 July in one climate-monitor dataset, but nothing in the current pricing suggests traders expect a repeat of the more extreme 90s-plus scenarios that are effectively negligible in this contract.[6][1]

The main late-stage catalysts are the usual weather drivers: updated National Weather Service short-range forecasts, any change in cloud cover or shower timing, and whether afternoon convection limits the peak at LaGuardia rather than elsewhere in the city.[12][1] Because the market settles on the station reading from Wunderground, traders are watching the actual LaGuardia observation cycle, not headline New York forecasts, and any revision to the day’s high will only matter until the first data point for the following date is published.[1] On the cross-platform read-through, the divergence is modest but real: Polymarket is split between two adjacent 80s bands, Robinhood is anchored one degree lower, and the broader forecast consensus still looks close enough that a small change in temperature timing could decide the winner.[1][4]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in NYC on August 3? 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

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Best Prediction Markets 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.