Highest temperature in Helsinki on July 4?

Platform comparison

Market context

The underlying event is the highest temperature recorded at Helsinki-Vantaa Airport on 4 July 2026, a date that historically marks the peak of Finland’s summer warmth. July is the hottest month at this station, with an average high of 71°F (21.7°C), making extreme heat plausible but not guaranteed[1]. Recent data from the past 15 days shows a peak of 80.4°F (26.9°C) on 2 July 2026, indicating that temperatures are already approaching seasonal highs[8].

Historically, July 4 in Helsinki has seen highs ranging from 65°F to 74°F (18.3°C to 23.3°C), with 2024’s July average hovering near the upper end of that band[4][9]. The current 0% YES probability suggests the market expects the temperature to fall below the lowest resolution threshold, which may be set unusually low or reflect a specific range definition. Traders should watch for any official weather bulletins from the Finnish Meteorological Institute, which releases daily maximums within 24 hours of observation[7]. Additionally, Wunderground’s real-time archive for EFHK will be the definitive settlement source, and any gaps in its data could delay resolution[2]. The market leans on the catalyst of immediate temperature confirmation rather than longer-term forecasts, as settlement ends precisely at 12:00 UTC on 4 July.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Political prediction markets differ structurally from sports betting: thinner liquidity, longer settlement windows, higher sensitivity to single news events. This page shows the live Polymarket quote for Highest temperature in Helsinki on July 4? plus platform attributes for the three reference venues, so you can see at a glance where the deepest market for this question sits.

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.

Can prediction markets influence election outcomes?

Markets reflect expectations rather than create them. Studies show public-facing markets can anchor expectations, but don't influence the underlying outcome. Political markets are information, not advocacy.

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 Election Predictions UK 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.