This prediction market asks whether Seattle's daily high temperature will fall between 46-47°F on May 19, 2026. The outcome resolves against the official National Weather Service measurement for Seattle-Tacoma International Airport, making it objectively verifiable. The 0% YES odds indicate strong trader conviction that the actual high will either exceed or fall short of this narrow 1-degree range. Mid-May Seattle weather is transitional—typically showing average highs around 66-67°F, though cool maritime air can produce outliers. A 46-47°F high would represent a significant cool snap, requiring unusual atmospheric conditions like a deep trough pushing cold air into the Pacific Northwest. Traders betting against this range suggest confidence in more typical spring temperatures or warmer patterns. The low liquidity ($6,144) relative to daily temperature markets reflects the challenge of predicting such a specific range; weather prediction at this precision level introduces substantial uncertainty even with modern forecasting. Volume of $603 in 24 hours shows modest interest typical of niche weather markets. The market remains open through the end of May 18, giving traders until then to adjust positions as forecasts update.
What factors could move this market?
Seattle in mid-May sits at a critical seasonal transition. Typically, the city experiences average highs of 66-67°F with average lows near 50°F, reflecting the warming trend from spring toward summer. However, the Pacific Northwest is susceptible to rapid weather reversals, particularly when upper-level troughs dip southward from Alaska or British Columbia, drawing cold maritime air into the region. For May 19 specifically to see a high of only 46-47°F would represent a significant departure from climate normals—roughly 20 degrees below the May average. Such an outcome requires a confluence of meteorological factors: a deep low-pressure system positioned offshore or inland, consistent cloud cover blocking solar heating, and northerly or northwesterly flow advecting cool air masses into western Washington. Historically, May cool snaps in Seattle do occur; the region has recorded May highs in the 40s on rare occasions, typically tied to systems moving through the Pacific Northwest in early or mid-month. However, the specificity of a 46-47°F range compounds the difficulty. A high of 45°F would miss the range; so would 48°F or any warmer reading. The 0% YES odds suggest traders believe the probability of landing precisely in this 1-degree band is negligible compared to outcomes outside it. Several factors support the current pricing. First, May weather models show declining skill at 7-10 day leads; precise range forecasting introduces compounding uncertainty. Second, even in cool-snap scenarios, daytime temperatures typically recover above 50°F given some sunshine penetration. Third, seasonal momentum in mid-May generally favors warming, not sustained cold. Conversely, factors supporting a 46-47°F high include the possibility of a slow-moving system with persistent cloudiness and cool air advection, though traders clearly view this as a low-probability tail outcome. The market's structure—with YES odds at 0%—reflects collective skepticism about both the likelihood of a significant cool snap and the precision required to land in such a narrow temperature window. Low liquidity and modest volume indicate this market occupies a niche within weather trading, likely attracting only highly specialized weather traders or enthusiasts with strong conviction in either spring warming or specific cool-snap forecasts.
What are traders watching for?
May 19 official high temperature from NOAA / National Weather Service Seattle-Tacoma station closes the market—only objective resolution criterion.
Extended forecast updates through May 18 will clarify whether cool-air advection or typical spring warmth dominates Seattle's mid-May pattern.
Upper-level atmospheric pattern and jet stream positioning in week of May 12-19 determines if troughs support significant cool anomaly.
Cloud cover and sunshine hours on May 19 directly influence daytime heating and maximum temperature achieved.
How does this market resolve?
Resolves YES if the National Weather Service official high temperature for Seattle-Tacoma International Airport on May 19, 2026 falls between 46.0°F and 47.9°F (inclusive). Market closes at 00:00 UTC on May 19.
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