Highest temperature in Los Angeles on July 22?

Platform comparison

Market context

Los Angeles International Airport’s highest temperature on 22 July will be read from the day’s station record, so the market is really about how hot LAX gets during the afternoon peak rather than the early-morning starting point. At 5 a.m. UTC on 23 July, AccuWeather showed Los Angeles at 83°F with a RealFeel of 97°F, which is consistent with a warm spell already in place as the day unfolded. [1]

The current crowd read is notably more decisive than a typical weather contract: the market is already pricing the 76–77°F band at 100%, which implies no meaningful distribution across the cooler buckets. [2] That looks at odds with the broader weather backdrop, where CBS News reported a Southern California heat wave and a National Weather Service heat advisory beginning at 10 a.m. on 22 July, suggesting the real-world temperature path depended heavily on whether marine influence held down the airport reading or inland heating pushed it higher. [3]

For traders comparing venues, the key point is that this contract is not a regional maximum-temperature forecast; it is a single-station outcome tied to the official LAX history page, so even a hot day elsewhere in Los Angeles would not matter unless the airport itself reached that range. [2] The main catalyst is the afternoon temperature peak at KLAX, with the final settle dependent on the highest reported reading on the station’s daily history record rather than a preliminary forecast or citywide average.

Sources: 1 · 2 · 3

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

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

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.

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.

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.