- Will Chicago, IL face tornado risk on August 23?1¢
- Will Houston, TX face tornado risk on August 23?1¢
- Will San Antonio, TX face tornado risk on August 23?3¢
- Will Dallas, TX face tornado risk on August 23?3¢
- Will Austin, TX face tornado risk on August 23?5¢
- Will Fort Worth, TX face tornado risk on August 23?3¢
- Will Columbus, OH face tornado risk on August 23?4¢
- Will Charlotte, NC face tornado risk on August 23?4¢
- Will Indianapolis, IN face tornado risk on August 23?3¢
- Will Denver, CO face tornado risk on August 23?4¢
- Will Nashville, TN face tornado risk on August 23?3¢
- Will Oklahoma City, OK face tornado risk on August 23?3¢
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 23, 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.
Low tornado risk prevailed across most of the U.S. on August 23, 2026, consistent with late-summer climatology when the polar jet stream shifts north and convective instability weakens. NOAA’s Storm Prediction Center outlooks indicated only isolated severe potential, with a single tornado warning issued in Florida’s Martin and St. Lucie counties amid otherwise minimal activity. Key drivers included limited low-level moisture, modest wind shear, and suppressed instability compared with peak-season months. Traders monitoring real-time SPC convective outlooks, NWS radar trends, and official warning polygons could assess city-specific exposure before resolution. Updated Day 1 and Day 2 products, plus post-event confirmation reports from local NWS offices, provide the primary data shifts affecting implied probabilities for affected locations.