Busan, South Korea's second-largest city on the Korean Strait, experiences variable weather in mid-May as spring transitions toward summer. This prediction market asks whether the highest temperature on May 17, 2026 will be exactly 27°C—a specific and measurable outcome based on official meteorological data. The 1% YES odds reflect extremely low trader conviction in this narrow outcome. With a historical May high around 25-29°C in Busan, traders taking YES at 1% assess this exact temperature as highly improbable; most traders expect the daily high to fall outside this single-degree band, whether cooler (22-26°C) or warmer (28-32°C). The market's thin liquidity ($5,872) and low 24-hour volume ($877) suggest minimal speculative activity, typical for hyperspecific weather forecasts. Temperature-targeting markets resolve against official Korean Meteorological Administration records, making this outcome deterministic by May 18, 2026. The market has tracked relatively flat, maintaining its bearish skew as traders collectively favor broader temperature ranges.
What factors could move this market?
Busan's meteorological profile during mid-May reflects the region's maritime subtropical climate. Located on the southern coast with the Korea Strait to the south, Busan experiences moderating ocean breezes that constrain temperature extremes compared to inland regions. May represents a transitional month: spring's variable patterns still dominate, but increasingly warmer air masses from the south begin exerting influence ahead of summer monsoon season. The Korean Meteorological Administration operates multiple weather stations across the metropolitan area, with the official observation site determining the recorded daily high. For a day to register exactly 27°C as its maximum is neither rare nor extraordinary in May—the range sits squarely within typical historical bounds—but the precision required dramatically reduces probability. The mechanism pushing toward YES involves a stable high-pressure system stalling over the peninsula, delivering moderate southerly winds with cloud cover limiting peak heating. A northbound warm front interacting with maritime air could yield precisely this temperature. Conversely, the mechanism pushing toward NO is more likely: cooler-than-normal air masses from the north could suppress highs to 24-26°C, while an intensifying heat dome or clear skies might push into 29-32°C. May's volatility means weather patterns shift rapidly; spring cold snaps or high-pressure ridges, both not uncommon, would push the market toward NO. Historically, Busan's May averages run 22°C (low) to 26°C (high), with records spanning 20-31°C. A 27°C high falls just above the 1981-2010 normal but well within observed variability. Recent springs showed May highs ranging 24-29°C, underscoring the absence of a locked pattern. The 1% odds imply traders see this outcome as a 99-to-1 long-shot. This severe discount reflects genuine uncertainty: single-degree temperature targeting requires sub-0.5°C precision, which modern forecasting cannot reliably predict 24-48 hours ahead. The thin liquidity likely embeds a 'liquidity penalty' where low volume exaggerates odds in either direction.
What are traders watching for?
Official KMA forecast issued May 15-16 determines trader expectations; monitor primary pressure systems across the peninsula
High-pressure ridge positioning: centered over Korea favors mid-range temps; eastward shift favors cooler or warmer extremes
Cloud cover on May 17: overcast mornings plus afternoon clearing favors warmer; persistent clouds suppress the high
Official KMA daily maximum temperature observation from Busan station on May 17 determines final market resolution
How does this market resolve?
The market resolves YES if the official Korean Meteorological Administration records the daily maximum temperature in Busan as exactly 27°C on May 17, 2026, and NO for any other temperature. Resolution occurs on May 18, 2026, once KMA publishes its final observation data.
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