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 locked on the 80–81°F range as the definitive outcome. The crowd-implied probability of 0% for any alternative outcome reflects near-total consensus that temperatures will not dip below this band, aligning with the frontrunner contract holding 100% probability on Polymarket[1]. This stands in stark contrast to earlier July forecasts, where the market correctly priced the 74–75°F peak on 4 July 2026, demonstrating its ability to nail specific heat events when data aligns[2].

Historical July heatwaves in Los Angeles, including the extreme event on 9 July 2026, show temperatures frequently climbing into the low 80s°F, with public health advisories urging residents to stay indoors during peak sun hours[3]. The current 0% probability for lower ranges mirrors this pattern, as recent extreme heat confirms that mid-July to late-July periods in LA consistently breach 80°F. Traders comparing Polymarket to Kalshi should note the divergence: while sportsbooks often lag on weather-specific contracts, prediction markets here have already resolved the outcome with high confidence, suggesting analyst consensus aligns tightly with the 80–81°F bracket.

Key catalysts for similar future contracts include Wunderground’s daily temperature logs for KLAX, which serve as the official resolution source, and any sudden shifts in regional weather patterns such as marine layer breaks or inland heat domes. No new announcements are pending for this settled market, but traders monitoring upcoming July 2027 contracts should watch NOAA heatwave forecasts and California Department of Public Health advisories, which often precede temperature spikes. The market’s precision on past July dates underscores its reliability for weather-based prediction, making it a benchmark for cross-platform odds comparisons.

Sources: 1 · 2 · 3

Methodology

We track Highest temperature in Los Angeles on July 20? 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

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is PolyGram. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.