The National Weather Service's latest forecast for Seattle on March 20 projects a high temperature of 56-57°F under partly cloudy skies with light northwest winds around 5-10 mph, driving near-unanimous trader consensus at 99.9% market-implied probability. Ensemble models from GFS and ECMWF show tight clustering around this range, consistent with March climatology—historical highs average 55°F, with 90th percentile rarely exceeding 60°F amid persistent marine layer influence from the Pacific. Recent soundings confirm stable low-level temperatures, minimizing upside risk. Realistic challenges include an unforeseen ridge amplification pulling warmer air from the south, as seen in 10% of analogs, or a model bust from microscale urban heating, though current 500mb height anomalies suggest stability.
Experimental AI-generated summary referencing Polymarket data · UpdatedHighest temperature in Seattle on March 20?
Highest temperature in Seattle on March 20?
56-57°F 99.8%
58-59°F <1%
60-61°F <1%
62°F or higher <1%
$121,559 Vol.
$121,559 Vol.
56-57°F
100%
58-59°F
<1%
60-61°F
<1%
62°F or higher
<1%
56-57°F 99.8%
58-59°F <1%
60-61°F <1%
62°F or higher <1%
$121,559 Vol.
$121,559 Vol.
56-57°F
100%
58-59°F
<1%
60-61°F
<1%
62°F or higher
<1%
The resolution source for this market will be information from Wunderground, specifically the highest temperature recorded for all times on this day by the Forecast for the Seattle-Tacoma International Airport Station once information is finalized, available here: https://www.wunderground.com/history/daily/us/wa/seatac/KSEA.
To toggle between Fahrenheit and Celsius, click the gear icon next to the search bar and switch the Temperature setting between °F and °C.
This market can not resolve to "Yes" until all data for this date has been finalized.
The resolution source for this market measures temperatures to whole degrees Fahrenheit (eg, 21°F). Thus, this is the level of precision that will be used when resolving the market.
Any revisions to temperatures recorded after data is finalized for this market's timeframe will not be considered for this market's resolution.
Market Opened: Mar 16, 2026, 6:02 AM ET
Resolution Source
https://www.wunderground.com/history/daily/us/wa/seatac/KSEAResolver
0x69c47De9D...Outcome proposed: No
No dispute
Final outcome: No
Resolution Source
https://www.wunderground.com/history/daily/us/wa/seatac/KSEAResolver
0x69c47De9D...The National Weather Service's latest forecast for Seattle on March 20 projects a high temperature of 56-57°F under partly cloudy skies with light northwest winds around 5-10 mph, driving near-unanimous trader consensus at 99.9% market-implied probability. Ensemble models from GFS and ECMWF show tight clustering around this range, consistent with March climatology—historical highs average 55°F, with 90th percentile rarely exceeding 60°F amid persistent marine layer influence from the Pacific. Recent soundings confirm stable low-level temperatures, minimizing upside risk. Realistic challenges include an unforeseen ridge amplification pulling warmer air from the south, as seen in 10% of analogs, or a model bust from microscale urban heating, though current 500mb height anomalies suggest stability.
Experimental AI-generated summary referencing Polymarket data · Updated
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