Highest temperature in San Francisco on July 13?

Platform comparison

Market context

San Francisco is entering its peak summer window with the 6% YES probability on a July 13 high temperature reflecting the city’s notorious marine moderation. Historical data shows the San Francisco International Airport (KSFO) rarely exceeds 90°F in July, with the all-time record for the station sitting at 87°F set in 2013, tied with a 1973 reading [1]. The broader Bay Area has seen extremes like 103°F in downtown San Francisco on June 13, 2000, but KSFO’s coastal exposure consistently buffers it from inland heat spikes [2]. This thermal inertia makes a temperature breach of the upper 80s or 90s statistically anomalous, justifying the low crowd-implied odds.

Traders should monitor the Pacific High pressure system and any incoming ridge development, as sustained high-pressure anomalies are the primary catalyst for Bay Area heat waves. Recent forecasts indicate typical July conditions with highs near 67°F, far below the threshold required to trigger a YES resolution [3]. While no scheduled political debates or campaign disclosures directly influence weather, the timing coincides with the end of the summer fire season prep, where meteorological agencies often issue heat advisories if ridge patterns strengthen. Watch the National Weather Service’s KSFO observations for real-time deviations, as a sudden shift in wind direction from the ocean could be the only variable altering the outcome [8].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page tracks Highest temperature in San Francisco on July 13? across four political prediction venues. Live odds come from the Polymarket order book (the deepest political prediction-market book). Kalshi is the CFTC-regulated US alternative, Betfair the established UK sports-exchange with politics markets, Manifold the open play-money variant. For users geo-blocked from Polymarket directly, brokers like Trump Prediction provide a 0%-fee route into the same order book.

Resolution & payout

Political markets typically settle on official candidate or agency confirmation. Polymarket uses UMA Optimistic Oracle: a proposer posts the outcome with a bond, the two-hour window opens, then the smart contract pays USDC.

Kalshi settles USD via CFTC clearinghouse, with clearly defined resolution sources (e.g. AP race calls for elections). Betfair settles after the official outcome is registered with the league or agency. Manifold is play-money.

FAQ

How accurate are political prediction markets?

Historically more accurate than polls. Polymarket's Brier score on US 2024 elections was ~0.11 — better than 538 (~0.14) and every mainstream poll. Markets aggregate information with real skin in the game.

Which platform has the deepest political liquidity?

Polymarket — by far. US 2024 presidential volume was ~$3.5B vs Kalshi (~$200M) and Betfair (~$120M). Where Polymarket is geo-blocked, brokers like Trump Prediction route into the same order book at 0% fees.

How fast do political markets react to news?

High-liquidity markets move within seconds to minutes. A Trump tweet on the economy can shift the "Trump 2024" market 2-5 points before mainstream media has written anything.

Why do Polymarket and Kalshi differ on elections?

Kalshi must follow CFTC compliance — strict definitions, clear resolution sources, US citizens only with KYC. Polymarket operates globally without CFTC oversight — deeper liquidity, but also higher regulatory risk.

Which political events have the biggest volume?

US Presidential election, party nominations (DNC/RNC), Senate majorities, individual state outcomes (Pennsylvania, Michigan, Wisconsin), and major European elections. Peak markets reach $50-500M per event.