Singapore in May sits squarely within the Southwest Monsoon season, characterized by warm, humid conditions with average daily highs ranging from 28 to 31°C and frequent afternoon thunderstorms. The current market price of 0% YES reflects trader conviction that a maximum temperature of exactly 25°C on May 18 is extremely unlikely. Such a cool high would require sustained cloud cover, prolonged rainfall, or an unusual cool air mass from surrounding regions—conditions that occur only rarely during Singapore's warm season. The question's specificity adds another layer of difficulty: traders must predict not just a cool day, but one where the highest temperature lands precisely at 25°C. Historical May weather data shows that even overcast, rainy days in Singapore rarely see maximum temperatures drop below 26°C. The market's near-zero odds suggest traders believe the probability of this specific outcome is negligible, though global atmospheric patterns occasionally deliver unexpected weather surprises that could shift the odds if conditions align in an unusually cool configuration. Market liquidity of $10,950 indicates baseline interest in Singapore weather trading despite the low conviction on this specific scenario.
What factors could move this market?
Singapore's climate is dominated by two monsoon systems. The Southwest Monsoon (May through September) brings moisture-laden winds from the Indian Ocean, resulting in higher rainfall and cloud cover compared to the Northeastern Monsoon that follows. During May, Singapore transitions fully into monsoon conditions, with average precipitation increasing and humidity remaining high throughout the month. The island's proximity to the equator means that even during monsoon season, temperatures rarely dip significantly below the seasonal norm. Average daily highs in May typically range from 28 to 31°C, while lows stay around 23 to 24°C. A maximum temperature of 25°C would represent a drop of at least 3°C below the seasonal average high, an anomaly that requires specific atmospheric conditions. For such a scenario to materialize, sustained heavy rainfall would need to dominate the day, preventing solar heating and allowing cool, wet air masses to suppress the maximum. Alternatively, an unusual weather system pushing cooler air from higher latitudes—though extremely rare so close to the equator—would be necessary. Historical records show that even during Singapore's rainiest May days, the maximum temperature rarely falls below 26 to 27°C. The city's urban heat island effect compounds this challenge, as the densely built environment tends to retain and release heat, pushing daytime maxima even higher than surrounding areas. From a meteorological standpoint, the current 0% odds reflect sound climate reasoning: the probability of such an unusually cool high on any given May day is genuinely low. Traders pricing this market are essentially saying that while weather remains inherently unpredictable over short timeframes, the specific structural conditions of Singapore's equatorial May climate make a 25°C maximum extremely improbable. The $517 in 24-hour volume and $10,950 liquidity suggest modest interest in this weather market, typical for daily temperature predictions on volatile but predictable markets. The near-zero YES odds leave room for substantial payouts should an unexpected weather pattern materialize, but current atmospheric indices and seasonal expectations offer little signal that such an anomaly approaches.
What are traders watching for?
May 18 cloud cover persistence: heavy monsoon clouds required all day; clear morning or afternoon breaks would push temperatures well above 25°C target.
Rainfall intensity threshold: sustained heavy rain exceeding 30mm by afternoon could suppress max temps, but light showers insufficient to reach 25°C.
Regional pressure systems: track whether unusual cooler air mass shifts south from India or Malaysia toward Singapore on May 18.
Historical May 18 baseline: Singapore's recorded max on May 18 averaged 28–30°C in past decade; 25°C would be 3°C below normal.
How does this market resolve?
This market resolves YES on May 18, 2026 at 00:00 UTC if the highest recorded temperature in Singapore that day is exactly 25°C. Otherwise it resolves NO.
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