Highest temperature in Helsinki on July 4?

Platform comparison

Market context

The real-world event this market tracks is the peak temperature recorded at Helsinki-Vantaa Airport on 4 July 2026, measured in degrees Celsius and sourced from Wunderground. Current crowd-implied probability for a YES outcome sits at 0%, yet market data shows "18°C" as the frontrunner with an 86% probability, followed by "19°C" at 14%[1]. This stark contrast between the zero-per-cent YES probability and the high likelihood of a specific temperature range mirrors historical patterns where Finland experienced record-breaking heatwaves, including 14 consecutive days above 30°C in Parikkala, breaking the 1972 record[9]. Such comparable cases, like the sweltering July heatwave that ended with temperatures above 30°C elsewhere in Finland[2], suggest that while extreme heat is possible, the specific threshold for a YES outcome may be calibrated conservatively against typical July highs averaging 71°F at this airport[3].

Traders should monitor the Finnish Meteorological Institute’s 72-hour forecast, which currently projects a daytime high of 19°C for 4 July with low model spread[6]. Key catalysts include official weather announcements and schedule updates from the Climate Service, especially given recent reports of Finland hitting 30.3°C in Parikkala[7]. Regulatory accessibility remains a critical factor: German GlüStV implications and US CFTC reach define the legal framework, while the "no-KYC up to $1,500" threshold allows traders to access this market without identity verification, provided they stay within the limit. This specific market’s accessibility hinges on these regulatory boundaries, ensuring compliance without hindering participation for smaller stakes.

The settlement window ends on 2026-07-04T12:00:00Z, meaning all data must be finalised before this timestamp. Recent forecasts indicate daily high temperatures ranging from 65° to 74° for July 2026 at Helsinki-Vantaa[5], reinforcing the plausibility of the 18°C or 19°C outcomes. While the market assigns a high probability to these temperatures, the 0% YES probability likely reflects a specific, perhaps higher, threshold for the YES condition that current forecasts do not meet. Traders must weigh these forecasted ranges against the regulatory landscape, where German and US laws intersect with the no-KYC provision to shape market participation.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This overview of Highest temperature in Helsinki on July 4? reviews the four comparable platforms from a regulatory perspective: which is accessible in your jurisdiction, where KYC kicks in, how the platform is classified by your country of residence. Live probability is the Polymarket mid; comparison columns show regulatory status, KYC thresholds and settlement options for each platform.

Resolution & payout

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FAQ

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