- Will Chicago, IL face tornado risk on August 29?<1¢
- Will Houston, TX face tornado risk on August 29?<1¢
- Will San Antonio, TX face tornado risk on August 29?<1¢
- Will Dallas, TX face tornado risk on August 29?<1¢
- Will Austin, TX face tornado risk on August 29?<1¢
- Will Fort Worth, TX face tornado risk on August 29?<1¢
- Will Columbus, OH face tornado risk on August 29?<1¢
- Will Charlotte, NC face tornado risk on August 29?<1¢
- Will Indianapolis, IN face tornado risk on August 29?<1¢
- Will Denver, CO face tornado risk on August 29?<1¢
- Will Nashville, TN face tornado risk on August 29?<1¢
- Will Oklahoma City, OK face tornado risk on August 29?<1¢
This market will resolve to "Yes" for each listed city that falls within a tornado probability area rated ≥2% in the NOAA Storm Prediction Center Day 1 Convective Outlook on August 29, 2026. Otherwise, this market will resolve to "No". The SPC Day 1 Convective Outlook assigns tornado probability percentages (2%, 5%, 10%, etc.) to geographic areas across the US. If a 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.
Traders evaluating tornado risk for cities on August 29 focus on the Storm Prediction Center’s daily convective outlooks, which assign probabilistic categories based on the potential for supercell thunderstorms. Primary scientific drivers include high convective available potential energy (CAPE) indicating atmospheric instability, strong low-level wind shear favoring rotation, and sufficient moisture combined with lift along fronts or drylines. NOAA’s National Weather Service refines these assessments through real-time radar, soundings, and updated model runs such as the HRRR, with actual tornado reports and damage surveys used for verification. Late-August patterns often feature lower overall frequency than spring peaks, though localized outbreaks remain possible where conditions align, and any last-minute model shifts or observed initiation can alter implied probabilities ahead of resolution.