The Storm Prediction Center's latest Day 1 convective outlook indicates only isolated 2% tornado probabilities across limited zones in the northern Plains and Upper Midwest, such as near Minneapolis, driven by modest low-level shear ahead of a southeastward-advancing cold front amid 2000+ J/kg MLCAPE. Primary severe threats remain damaging winds and large hail from supercells or clusters, consistent with orographic and frontal lift over the central High Plains. Historical August patterns show lower tornado frequency than spring peaks, with current model consensus favoring limited tornadic potential due to weak hodographs. Updated SPC outlooks, new NWS radar data, and afternoon model runs will refine risk areas for any late-day activity.
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 25?
Chicago, IL
3%
Houston, TX
4%
San Antonio, TX
5%
Dallas, TX
5%
Austin, TX
3%
Fort Worth, TX
5%
Columbus, OH
5%
Charlotte, NC
5%
Indianapolis, IN
6%
Denver, CO
5%
Nashville, TN
3%
Oklahoma City, OK
6%
Memphis, TN
5%
Louisville, KY
5%
Atlanta, GA
2%
Kansas City, MO
5%
Omaha, NE
5%
Minneapolis, MN
7%
Wichita, KS
5%
New Orleans, LA
5%
Tampa, FL
5%
St. Louis, MO
5%
Birmingham, AL
5%
Des Moines, IA
5%
Little Rock, AR
6%
$1,208 Vol.
Chicago, IL
3%
Houston, TX
4%
San Antonio, TX
5%
Dallas, TX
5%
Austin, TX
3%
Fort Worth, TX
5%
Columbus, OH
5%
Charlotte, NC
5%
Indianapolis, IN
6%
Denver, CO
5%
Nashville, TN
3%
Oklahoma City, OK
6%
Memphis, TN
5%
Louisville, KY
5%
Atlanta, GA
2%
Kansas City, MO
5%
Omaha, NE
5%
Minneapolis, MN
7%
Wichita, KS
5%
New Orleans, LA
5%
Tampa, FL
5%
St. Louis, MO
5%
Birmingham, AL
5%
Des Moines, IA
5%
Little Rock, AR
6%
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 25, 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...The Storm Prediction Center's latest Day 1 convective outlook indicates only isolated 2% tornado probabilities across limited zones in the northern Plains and Upper Midwest, such as near Minneapolis, driven by modest low-level shear ahead of a southeastward-advancing cold front amid 2000+ J/kg MLCAPE. Primary severe threats remain damaging winds and large hail from supercells or clusters, consistent with orographic and frontal lift over the central High Plains. Historical August patterns show lower tornado frequency than spring peaks, with current model consensus favoring limited tornadic potential due to weak hodographs. Updated SPC outlooks, new NWS radar data, and afternoon model runs will refine risk areas for any late-day activity.
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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