**National Weather Service forecasters issued a tornado warning on August 23 for portions of Florida’s Treasure Coast, including Martin and St. Lucie counties near Melbourne, after radar detected rotation in a nearly stationary severe thunderstorm capable of producing a tornado and hail up to 0.75 inches.** SPC Day 1 and Day 2 outlooks that day highlighted only marginal or low tornado probabilities overall, with isolated supercell potential confined mainly to the northern High Plains and Great Basin where wind and hail threats dominated. Weak deep-layer shear and modest instability across most of the eastern U.S. limited broader tornadic risk, consistent with typical late-August climatology when activity shifts northward and becomes more pulse-driven. Traders monitoring real-time SPC updates and local NWS warnings would have focused on the Florida alert as the clearest signal for any city-specific resolution.
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 23?
$15,571 Vol.

Chicago, IL
No

Houston, TX
No

San Antonio, TX
No

Dallas, TX
No

Austin, TX
No

Fort Worth, TX
No

Columbus, OH
No

Charlotte, NC
No

Indianapolis, IN
No

Denver, CO
No

Nashville, TN
No

Oklahoma City, OK
No

Memphis, TN
No

Louisville, KY
No

Atlanta, GA
No

Kansas City, MO
No

Omaha, NE
No

Minneapolis, MN
No

Wichita, KS
No

New Orleans, LA
No

Tampa, FL
No

St. Louis, MO
No

Birmingham, AL
No

Des Moines, IA
No

Little Rock, AR
No
$15,571 Vol.

Chicago, IL
No

Houston, TX
No

San Antonio, TX
No

Dallas, TX
No

Austin, TX
No

Fort Worth, TX
No

Columbus, OH
No

Charlotte, NC
No

Indianapolis, IN
No

Denver, CO
No

Nashville, TN
No

Oklahoma City, OK
No

Memphis, TN
No

Louisville, KY
No

Atlanta, GA
No

Kansas City, MO
No

Omaha, NE
No

Minneapolis, MN
No

Wichita, KS
No

New Orleans, LA
No

Tampa, FL
No

St. Louis, MO
No

Birmingham, AL
No

Des Moines, IA
No

Little Rock, AR
No
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 33.749, -84.388 for Atlanta, GA.
Market Opened: Aug 23, 2026, 8:13 AM ET
Resolution Source
https://www.spc.noaa.gov/products/outlook/day1otlk.htmlResolver
0x65070BE91...Outcome proposed: No
No dispute
Final outcome: No
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 33.749, -84.388 for Atlanta, GA.
Resolution Source
https://www.spc.noaa.gov/products/outlook/day1otlk.htmlResolver
0x65070BE91...Outcome proposed: No
No dispute
Final outcome: No
**National Weather Service forecasters issued a tornado warning on August 23 for portions of Florida’s Treasure Coast, including Martin and St. Lucie counties near Melbourne, after radar detected rotation in a nearly stationary severe thunderstorm capable of producing a tornado and hail up to 0.75 inches.** SPC Day 1 and Day 2 outlooks that day highlighted only marginal or low tornado probabilities overall, with isolated supercell potential confined mainly to the northern High Plains and Great Basin where wind and hail threats dominated. Weak deep-layer shear and modest instability across most of the eastern U.S. limited broader tornadic risk, consistent with typical late-August climatology when activity shifts northward and becomes more pulse-driven. Traders monitoring real-time SPC updates and local NWS warnings would have focused on the Florida alert as the clearest signal for any city-specific resolution.
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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