SPC convective outlooks for August 27, 2026, established the primary driver for trader positioning, with a Slight risk category and 2% tornado probabilities centered on the Mid-Atlantic and Northeast. An elongated upper-level trough and surface front promoted moderate destabilization and sufficient deep-layer shear for organized multicell and supercell storms capable of isolated tornadoes, alongside damaging winds and hail. Larger population centers such as New York, Philadelphia, Baltimore, and Newark fell within the probabilistic tornado area per official model guidance including NAM and RAP soundings. Central Plains regions carried mainly wind and hail threats with negligible tornado signals. With resolution tied to confirmed tornado reports within defined geographic boundaries, traders monitored real-time SPC updates and NWS verification data through the evening convective window.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · UpdatedWhich cities face tornado risk on August 27?
Chicago, IL
<1%
Houston, TX
<1%
San Antonio, TX
<1%
Dallas, TX
<1%
Austin, TX
<1%
Fort Worth, TX
<1%
Columbus, OH
<1%
Charlotte, NC
<1%
Indianapolis, IN
<1%
Denver, CO
1%
Nashville, TN
<1%
Oklahoma City, OK
<1%
Memphis, TN
<1%
Louisville, KY
1%
Atlanta, GA
1%
Kansas City, MO
1%
Omaha, NE
<1%
Minneapolis, MN
<1%
Wichita, KS
<1%
New Orleans, LA
1%
Tampa, FL
<1%
St. Louis, MO
<1%
Birmingham, AL
<1%
Des Moines, IA
<1%
Little Rock, AR
<1%
$7,252 Vol.
Chicago, IL
<1%
Houston, TX
<1%
San Antonio, TX
<1%
Dallas, TX
<1%
Austin, TX
<1%
Fort Worth, TX
<1%
Columbus, OH
<1%
Charlotte, NC
<1%
Indianapolis, IN
<1%
Denver, CO
1%
Nashville, TN
<1%
Oklahoma City, OK
<1%
Memphis, TN
<1%
Louisville, KY
1%
Atlanta, GA
1%
Kansas City, MO
1%
Omaha, NE
<1%
Minneapolis, MN
<1%
Wichita, KS
<1%
New Orleans, LA
1%
Tampa, FL
<1%
St. Louis, MO
<1%
Birmingham, AL
<1%
Des Moines, IA
<1%
Little Rock, AR
<1%
The SPC Day 1 Convective Outlook assigns tornado probability percentages (2%, 5%, 10%, etc.) to geographic areas across the US. If the city's coordinates fall inside any area rated 2% or higher, that city resolves "Yes". If a city is outside all tornado probability areas, or only within areas rated below 2%, that city resolves "No".
The SPC outlook is published as machine-readable geographic data (GeoJSON) at spc.noaa.gov. Each city's coordinates and the polygon boundaries are publicly verifiable. Borderline cases can be independently confirmed using the polygon data (excluding the hatched SIGN overlay, which is not a probability rating) and the city's listed coordinates. The point-in-polygon test is performed on unprojected WGS84 (EPSG:4326) coordinates, which is the native coordinate system of the SPC GeoJSON data.
Resolution is based on the scheduled 01:00 UTC Day 1 Convective Outlook update issued on the following UTC calendar day. The SPC Day 1 outlook covers a 24-hour period from 12:00 UTC to 12:00 UTC the following day. Subsequent revisions published after that scheduled update will not be considered. If the SPC outlook is not published or is unavailable, the market remains open until data is available.
The resolution source for this market is the NOAA Storm Prediction Center at spc.noaa.gov.
This market uses coordinates 41.8781, -87.6298 for Chicago, IL.
Market Opened: Aug 27, 2026, 8:13 AM ET
Resolution Source
https://www.spc.noaa.gov/products/outlook/day1otlk.htmlResolver
0x65070BE91...The SPC Day 1 Convective Outlook assigns tornado probability percentages (2%, 5%, 10%, etc.) to geographic areas across the US. If the city's coordinates fall inside any area rated 2% or higher, that city resolves "Yes". If a city is outside all tornado probability areas, or only within areas rated below 2%, that city resolves "No".
The SPC outlook is published as machine-readable geographic data (GeoJSON) at spc.noaa.gov. Each city's coordinates and the polygon boundaries are publicly verifiable. Borderline cases can be independently confirmed using the polygon data (excluding the hatched SIGN overlay, which is not a probability rating) and the city's listed coordinates. The point-in-polygon test is performed on unprojected WGS84 (EPSG:4326) coordinates, which is the native coordinate system of the SPC GeoJSON data.
Resolution is based on the scheduled 01:00 UTC Day 1 Convective Outlook update issued on the following UTC calendar day. The SPC Day 1 outlook covers a 24-hour period from 12:00 UTC to 12:00 UTC the following day. Subsequent revisions published after that scheduled update will not be considered. If the SPC outlook is not published or is unavailable, the market remains open until data is available.
The resolution source for this market is the NOAA Storm Prediction Center at spc.noaa.gov.
This market uses coordinates 41.8781, -87.6298 for Chicago, IL.
Resolution Source
https://www.spc.noaa.gov/products/outlook/day1otlk.htmlResolver
0x65070BE91...SPC convective outlooks for August 27, 2026, established the primary driver for trader positioning, with a Slight risk category and 2% tornado probabilities centered on the Mid-Atlantic and Northeast. An elongated upper-level trough and surface front promoted moderate destabilization and sufficient deep-layer shear for organized multicell and supercell storms capable of isolated tornadoes, alongside damaging winds and hail. Larger population centers such as New York, Philadelphia, Baltimore, and Newark fell within the probabilistic tornado area per official model guidance including NAM and RAP soundings. Central Plains regions carried mainly wind and hail threats with negligible tornado signals. With resolution tied to confirmed tornado reports within defined geographic boundaries, traders monitored real-time SPC updates and NWS verification data through the evening convective window.
Experimental AI-generated summary referencing Polymarket data. This is not trading advice and plays no role in how this market resolves. · Updated

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