The Storm Prediction Center’s latest Day 1 convective outlook places a Marginal risk of severe thunderstorms across the Carolinas into northern Georgia, Iowa, the central High Plains, and Intermountain West, driven by a southward-moving cold front, moderate instability from dewpoints in the 60s–70s°F, and daytime heating. Tornado probabilities remain very low, with only a 2% contour over parts of Iowa where low-level warm-air advection and slightly enlarged hodographs could support isolated, short-lived supercells; damaging winds and hail dominate elsewhere. Model consensus favors limited shear overall, keeping organized tornado threats modest compared with historical September baselines. Traders should monitor the next SPC update around 1630Z and any National Weather Service watches or warnings for real-time shifts in the Iowa or Carolinas corridors.
Експериментальне резюме, згенероване ШІ з посиланням на дані Polymarket. Це не торгова порада і не впливає на вирішення цього ринку. · ОновленоWhich cities face tornado risk on September 18?
Chicago, IL
2%
Houston, TX
50%
San Antonio, TX
2%
Dallas, TX
50%
Austin, TX
2%
Fort Worth, TX
2%
Columbus, OH
2%
Charlotte, NC
2%
Indianapolis, IN
2%
Denver, CO
2%
Nashville, TN
2%
Oklahoma City, OK
2%
Memphis, TN
2%
Louisville, KY
2%
Atlanta, GA
2%
Kansas City, MO
2%
Omaha, NE
50%
Minneapolis, MN
2%
Wichita, KS
2%
New Orleans, LA
2%
Tampa, FL
2%
St. Louis, MO
2%
Birmingham, AL
2%
Des Moines, IA
50%
Little Rock, AR
2%
$22 Обс.
Chicago, IL
2%
Houston, TX
50%
San Antonio, TX
2%
Dallas, TX
50%
Austin, TX
2%
Fort Worth, TX
2%
Columbus, OH
2%
Charlotte, NC
2%
Indianapolis, IN
2%
Denver, CO
2%
Nashville, TN
2%
Oklahoma City, OK
2%
Memphis, TN
2%
Louisville, KY
2%
Atlanta, GA
2%
Kansas City, MO
2%
Omaha, NE
50%
Minneapolis, MN
2%
Wichita, KS
2%
New Orleans, LA
2%
Tampa, FL
2%
St. Louis, MO
2%
Birmingham, AL
2%
Des Moines, IA
50%
Little Rock, AR
2%
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.
Ринок відкрито: Sep 18, 2026, 8:13 AM ET
Джерело вирішення
https://www.spc.noaa.gov/products/outlook/day1otlk.htmlВирішувач
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.
Джерело вирішення
https://www.spc.noaa.gov/products/outlook/day1otlk.htmlВирішувач
0x65070BE91...The Storm Prediction Center’s latest Day 1 convective outlook places a Marginal risk of severe thunderstorms across the Carolinas into northern Georgia, Iowa, the central High Plains, and Intermountain West, driven by a southward-moving cold front, moderate instability from dewpoints in the 60s–70s°F, and daytime heating. Tornado probabilities remain very low, with only a 2% contour over parts of Iowa where low-level warm-air advection and slightly enlarged hodographs could support isolated, short-lived supercells; damaging winds and hail dominate elsewhere. Model consensus favors limited shear overall, keeping organized tornado threats modest compared with historical September baselines. Traders should monitor the next SPC update around 1630Z and any National Weather Service watches or warnings for real-time shifts in the Iowa or Carolinas corridors.
Експериментальне резюме, згенероване ШІ з посиланням на дані Polymarket. Це не торгова порада і не впливає на вирішення цього ринку. · Оновлено

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