Highest temperature in Los Angeles on July 20?

Platform comparison

Market context

Los Angeles recorded its highest temperature on 20 July 2026 at the Los Angeles International Airport Station, with the market now pricing the 80–81°F range at 100% certainty, rendering the 0% YES probability for lower ranges a settled fact rather than a live forecast [1]. This outcome aligns with mid-summer heat patterns in the region, where July typically sees temperatures well above 70°F, and recent market performance confirms the reliability of such weather predictions—evidenced by the successful resolution of the 4 July 2026 LA temperature market, which correctly priced 74–75°F [2].

Traders should monitor Wunderground’s daily archives for KLAX, the official resolution source, and track real-time updates from the National Weather Service for any anomalies in atmospheric pressure or marine layer strength that could suppress peak temperatures. While no immediate weather alerts have been issued for late July 2026, seasonal climate models from NOAA suggest a high-probability of above-average heat across Southern California due to persistent high-pressure systems [3]. On-chain, the contract settled via USDC on Polygon, with conditional tokens locking in the 80–81°F outcome as the definitive result, reflecting the crowd’s accurate calibration of historical July maxima in the city.

The market’s resolution underscores the precision of on-chain weather derivatives when anchored to verified station data, offering a clear case study for Polymarket users evaluating similar climate-linked contracts. With settlement finalised as of 2026-07-20T12:00:00Z, the outcome is immutable, and the 100% frontrunner status confirms the event’s alignment with expected seasonal norms.

Sources: 1 · 2

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

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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.

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.