First Warning

First Warning is the name of a severe weather warning system designed for broadcast television stations, typically those in the United States. A weather advisory product based on First Warning, called First Alert, is an automated version of this product, which has come into widespread use by television stations and is marketed under different names depending on the graphics service vendor.

Both products are typically used by television stations that have an in-house news and weather operation, although some television stations that do not broadcast news at all or have their newscasts produced by another station in their market may use the system as well.

First Warning was created in 1990 by Gary England, then the chief meteorologist of CBS affiliate KWTV in Oklahoma City, Oklahoma (a city which historically has had the highest number of tornado strikes of any U.S. city since tornado records began to be logged in 1890), and went into use in the spring of 1991. The system was conceived to provide visual alerts for severe and winter weather as well as other hydrologic and non-hydrologic weather advisories to television viewers in a timely and convenient manner. The original version of this forecast product required manual input of weather alerts into the computer system by a meteorologist, with the specific advisory information, the counties/parishes listed in the alert and the advisory type.

ABC affiliate KOCO-TV, a market competitor to KWTV, created an automated version of this product called First Alert (a name the station has since used for its doppler radar system, now known as "Advantage Doppler HD", and which the station currently uses as its weather branding), in which the weather information is updated by the computer itself, delivered by communication routes wired to media outlets from the National Weather Service.Tornado sirens are also usually activated for the affected areas if present. and parses out additional text included in the alert product including the date and time of issuance, SAME county codes and other text coding that precedes and follows the main body of the alert product.

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