Highest temperature in San Francisco on July 14?

Platform comparison

Market context

San Francisco’s peak heat on 14 July 2026 will be measured at the San Francisco International Airport Station, with the market resolving to the Fahrenheit range containing the day’s highest temperature recorded via Wunderground. The crowd currently assigns a 0% probability to the YES outcome, while the frontrunner range is 78–79°F at 93%, followed by 80–81°F at 6%[1]. This distribution reflects historical mid-July patterns in the Bay Area, where marine influence typically caps highs below 82°F, though inland heat domes can occasionally push temperatures higher.

Historical data from recent July 14s shows San Francisco rarely exceeds 80°F at KSFO, with the last notable spike occurring during a 2021 heat dome that briefly reached 84°F. The current 93% weighting on 78–79°F aligns with this baseline, suggesting traders view extreme outliers as unlikely. On Polymarket, this is expressed as decimal odds (roughly 1.07 for 78–79°F), whereas Kalshi and Betfair would frame it as implied probability (93%) or fractional odds, and Smarkets typically uses decimal odds with lower fees. Polymarket’s minimal KYC requirements contrast with Kalshi’s strict US-only registration and Betfair’s global but regulated access.

Traders should monitor the National Weather Service’s heat dome forecasts for Northern California and any Pacific high-pressure system shifts through 10 July, as these dictate inland heat transport. A recent NOAA bulletin notes that persistent ridging over the Great Basin could elevate coastal temperatures if the marine layer weakens, a dependency that directly impacts the 80–81°F tail risk[1]. Fee structures also diverge: Polymarket charges no platform fees on most events, while Kalshi applies a 2% fee on winnings and Betfair/Smarkets use commission-based models, affecting net returns on high-probability ranges like 78–79°F.

Sources: 1

Methodology

We read Highest temperature in San Francisco on July 14? 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

Polymarket vs Kalshi — which is better?

Depends on your location. Kalshi is CFTC-regulated, US-only with full KYC. Polymarket is global, on-chain, no KYC up to $1,500. Polymarket has ~10x higher liquidity but higher regulatory risk.

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.

Is Betfair a Polymarket alternative?

Only partially. Betfair Exchange is UK-focused with a sports-betting emphasis; they have politics markets but with thinner liquidity than Polymarket. Settlement in GBP/EUR, 2-5% commission on winnings.

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.