NOAA's Storm Prediction Center convective outlooks for August 23, 2026, indicate predictability too low for organized severe thunderstorms across most regions, keeping tornado probabilities minimal outside isolated cells. Weak low-level flow and limited instability from current atmospheric patterns suppress widespread supercell development, consistent with late-summer climatology where tornado frequency drops outside peak spring setups. Traders are monitoring any last-minute SPC Day 1 updates or mesoscale discussions for localized wind shear increases that could elevate risk in the Plains or Midwest. Official NOAA guidance remains the resolution benchmark, with model consensus expected to refine as the event window approaches.
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?

Chicago, IL
6%

Houston, TX
10%

San Antonio, TX
6%

Dallas, TX
5%

Austin, TX
10%

Fort Worth, TX
5%

Columbus, OH
7%

Charlotte, NC
7%

Indianapolis, IN
6%

Denver, CO
9%

Nashville, TN
10%

Oklahoma City, OK
8%

Memphis, TN
6%

Louisville, KY
6%

Atlanta, GA
6%

Kansas City, MO
6%

Omaha, NE
6%

Minneapolis, MN
7%

Wichita, KS
5%

New Orleans, LA
5%

Tampa, FL
5%

St. Louis, MO
5%

Birmingham, AL
6%

Des Moines, IA
6%

Little Rock, AR
5%
$1,408 Vol.

Chicago, IL
6%

Houston, TX
10%

San Antonio, TX
6%

Dallas, TX
5%

Austin, TX
10%

Fort Worth, TX
5%

Columbus, OH
7%

Charlotte, NC
7%

Indianapolis, IN
6%

Denver, CO
9%

Nashville, TN
10%

Oklahoma City, OK
8%

Memphis, TN
6%

Louisville, KY
6%

Atlanta, GA
6%

Kansas City, MO
6%

Omaha, NE
6%

Minneapolis, MN
7%

Wichita, KS
5%

New Orleans, LA
5%

Tampa, FL
5%

St. Louis, MO
5%

Birmingham, AL
6%

Des Moines, IA
6%

Little Rock, AR
5%
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 23, 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...NOAA's Storm Prediction Center convective outlooks for August 23, 2026, indicate predictability too low for organized severe thunderstorms across most regions, keeping tornado probabilities minimal outside isolated cells. Weak low-level flow and limited instability from current atmospheric patterns suppress widespread supercell development, consistent with late-summer climatology where tornado frequency drops outside peak spring setups. Traders are monitoring any last-minute SPC Day 1 updates or mesoscale discussions for localized wind shear increases that could elevate risk in the Plains or Midwest. Official NOAA guidance remains the resolution benchmark, with model consensus expected to refine as the event window approaches.
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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