The NOAA Storm Prediction Center's Day 1 convective outlooks for August 19, 2026, placed only marginal-to-slight severe risk across limited portions of the central and southern Plains and Midwest, with tornado probabilities capped at 2–5% in those contours due to modest instability, weak deep-layer shear, and a tendency for storms to form linear segments favoring damaging winds over discrete supercells. This subdued setup aligned with typical August climatology of reduced tornado frequency outside peak spring patterns. Actual post-event reports confirmed an isolated EF-1 tornado in western Kentucky amid broader wind and hail events, but market resolution hinges strictly on the official outlook polygons rather than confirmations. Traders are watching for any final NWS survey revisions or model reanalyses that could retroactively adjust city inclusions.
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 19?
$2,492 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
$2,492 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.
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 19, 2026, 2:03 PM 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.
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...Outcome proposed: No
No dispute
Final outcome: No
The NOAA Storm Prediction Center's Day 1 convective outlooks for August 19, 2026, placed only marginal-to-slight severe risk across limited portions of the central and southern Plains and Midwest, with tornado probabilities capped at 2–5% in those contours due to modest instability, weak deep-layer shear, and a tendency for storms to form linear segments favoring damaging winds over discrete supercells. This subdued setup aligned with typical August climatology of reduced tornado frequency outside peak spring patterns. Actual post-event reports confirmed an isolated EF-1 tornado in western Kentucky amid broader wind and hail events, but market resolution hinges strictly on the official outlook polygons rather than confirmations. Traders are watching for any final NWS survey revisions or model reanalyses that could retroactively adjust city inclusions.
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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