The latest National Weather Service Storm Prediction Center Day 1 convective outlook, valid through September 22, identifies no tornado risk areas across the contiguous U.S., with only a marginal severe thunderstorm area focused on isolated damaging winds in the Southeast and central Appalachians plus limited hail potential over the Texas South Plains. A cold front interacting with multiple mesoscale convective vortices and modest instability (around 2000 J/kg MLCAPE) favors multicell clusters capable of wind gusts rather than rotating supercells, given limited vertical wind shear. Historical September patterns show lower tornado frequency in these regions compared to peak spring months. Traders should monitor subsequent SPC updates and real-time radar for any unexpected shear increases that could alter the zero-probability assessment before the period ends.
Riepilogo sperimentale generato dall'AI con riferimento ai dati di Polymarket. Questo non è un consiglio di trading e non ha alcun ruolo nella risoluzione di questo mercato. · AggiornatoQuali città affrontano il rischio di tornado il 21 settembre?
Chicago, IL
2%
Houston, TX
4%
San Antonio, TX
4%
Dallas, TX
4%
Austin, TX
2%
Fort Worth, TX
4%
Columbus, OH
4%
Charlotte, NC
4%
Indianapolis, IN
4%
Denver, CO
2%
Nashville, TN
4%
Oklahoma City, OK
4%
Memphis, TN
26%
Louisville, KY
12%
Atlanta, GA
2%
Kansas City, MO
2%
Omaha, NE
2%
Minneapolis, MN
2%
Wichita, KS
2%
New Orleans, LA
2%
Tampa, FL
4%
St. Louis, MO
4%
Birmingham, AL
4%
Des Moines, IA
25%
Little Rock, AR
26%
$497 Vol.
Chicago, IL
2%
Houston, TX
4%
San Antonio, TX
4%
Dallas, TX
4%
Austin, TX
2%
Fort Worth, TX
4%
Columbus, OH
4%
Charlotte, NC
4%
Indianapolis, IN
4%
Denver, CO
2%
Nashville, TN
4%
Oklahoma City, OK
4%
Memphis, TN
26%
Louisville, KY
12%
Atlanta, GA
2%
Kansas City, MO
2%
Omaha, NE
2%
Minneapolis, MN
2%
Wichita, KS
2%
New Orleans, LA
2%
Tampa, FL
4%
St. Louis, MO
4%
Birmingham, AL
4%
Des Moines, IA
25%
Little Rock, AR
26%
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 Day 1 Convective Outlook has not been published by the time the market closes, this market will resolve to "No".
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.
Mercato aperto: Sep 21, 2026, 8:13 AM ET
Fonte di risoluzione
https://www.spc.noaa.gov/products/outlook/day1otlk.htmlRisolutore
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 Day 1 Convective Outlook has not been published by the time the market closes, this market will resolve to "No".
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.
Fonte di risoluzione
https://www.spc.noaa.gov/products/outlook/day1otlk.htmlRisolutore
0x65070BE91...The latest National Weather Service Storm Prediction Center Day 1 convective outlook, valid through September 22, identifies no tornado risk areas across the contiguous U.S., with only a marginal severe thunderstorm area focused on isolated damaging winds in the Southeast and central Appalachians plus limited hail potential over the Texas South Plains. A cold front interacting with multiple mesoscale convective vortices and modest instability (around 2000 J/kg MLCAPE) favors multicell clusters capable of wind gusts rather than rotating supercells, given limited vertical wind shear. Historical September patterns show lower tornado frequency in these regions compared to peak spring months. Traders should monitor subsequent SPC updates and real-time radar for any unexpected shear increases that could alter the zero-probability assessment before the period ends.
Riepilogo sperimentale generato dall'AI con riferimento ai dati di Polymarket. Questo non è un consiglio di trading e non ha alcun ruolo nella risoluzione di questo mercato. · Aggiornato

Fai attenzione ai link esterni.
Fai attenzione ai link esterni.
Domande frequenti