The latest NWS Storm Prediction Center Day 1 Convective Outlook (valid through 12Z September 19) places only a Marginal risk of severe thunderstorms across the Carolina Piedmont into northern Georgia, northern Iowa, the central High Plains, and Intermountain West, driven by weak frontal boundaries, diurnal heating, and modest instability. Tornado probabilities stay very low, with a narrow 2% contour mainly over parts of Iowa; elsewhere, weak deep-layer shear and outflow-dominant storm modes limit tornadic potential in favor of isolated damaging winds or small hail. Official updates from the SPC and National Weather Service will refine short-term threats through the evening as new radar and model data arrive.
Resumo experimental gerado por IA com dados do Polymarket. Isto não é aconselhamento de trading e não tem qualquer papel na resolução deste mercado. · AtualizadoQuais cidades enfrentam risco de tornado em 18 de setembro?
Chicago, IL
50%
Houston, TX
25%
San Antonio, TX
25%
Dallas, TX
25%
Austin, TX
25%
Fort Worth, TX
25%
Columbus, OH
25%
Charlotte, NC
26%
Indianápolis, IN
26%
Denver, CO
26%
Nashville, TN
2%
Oklahoma City, OK
26%
Memphis, TN
26%
Louisville, KY
2%
Atlanta, GA
2%
Kansas City, MO
25%
Omaha, NE
1%
Minneapolis, MN
2%
Wichita, KS
26%
Nova Orleans, LA
25%
Tampa, FL
13%
St. Louis, MO
50%
Birmingham, AL
50%
Des Moines, IA
36%
Little Rock, AR
1%
$296 Vol.
Chicago, IL
50%
Houston, TX
25%
San Antonio, TX
25%
Dallas, TX
25%
Austin, TX
25%
Fort Worth, TX
25%
Columbus, OH
25%
Charlotte, NC
26%
Indianápolis, IN
26%
Denver, CO
26%
Nashville, TN
2%
Oklahoma City, OK
26%
Memphis, TN
26%
Louisville, KY
2%
Atlanta, GA
2%
Kansas City, MO
25%
Omaha, NE
1%
Minneapolis, MN
2%
Wichita, KS
26%
Nova Orleans, LA
25%
Tampa, FL
13%
St. Louis, MO
50%
Birmingham, AL
50%
Des Moines, IA
36%
Little Rock, AR
1%
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.
Mercado Aberto: Sep 18, 2026, 8:13 AM ET
Fonte de resolução
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 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 de resolução
https://www.spc.noaa.gov/products/outlook/day1otlk.htmlResolver
0x65070BE91...The latest NWS Storm Prediction Center Day 1 Convective Outlook (valid through 12Z September 19) places only a Marginal risk of severe thunderstorms across the Carolina Piedmont into northern Georgia, northern Iowa, the central High Plains, and Intermountain West, driven by weak frontal boundaries, diurnal heating, and modest instability. Tornado probabilities stay very low, with a narrow 2% contour mainly over parts of Iowa; elsewhere, weak deep-layer shear and outflow-dominant storm modes limit tornadic potential in favor of isolated damaging winds or small hail. Official updates from the SPC and National Weather Service will refine short-term threats through the evening as new radar and model data arrive.
Resumo experimental gerado por IA com dados do Polymarket. Isto não é aconselhamento de trading e não tem qualquer papel na resolução deste mercado. · Atualizado

Cuidado com os links externos.
Cuidado com os links externos.
Frequently Asked Questions