Early Warning Sirens
Frequently Asked Questions
Q. When and how are the Early Warning Sirens activated?
A. At the direction of the Emergency Management Coordinator, standard policy for Longview Public Safety Communications is to activate the Early Warning Sirens (EWS) whenever Gregg County is placed under a tornado warning. This is due to the relatively small size of the county and the need for as much prior notice as possible when dealing with dangerous storms. Activations are typically initiated when the National Weather Service (NWS) issues a tornado warning, or when a Skywarn Representative advises of a confirmed sighting in our jurisdiction. Standard procedure is to activate the sirens until the warning is lifted, or until a representative from either the NWS or Skywarn advises that the "warned" storm is no longer threatening our area.
Q. What should I do if I hear a siren?
A. If you hear a siren, you should head for cover and seek information about possible severe weather in the area.
Q. When are the sirens tested?
A. The sirens are tested on the first Wednesday of the month at noon. If there is a threat of severe weather on that day, the siren test will not be conducted.
Q. Do the sirens work if the power goes out?
A. All sirens are equipped with a battery back-up at each location, which are designed to provide power for the siren to continue running for approximately 15 minutes.
Q. When was the last time the system was evaluated for siren coverage and possible need for more sirens? Are there plans to add more sirens?
A. The upgrade of the siren system was completed in 2011 – 2012, which included replacement of the siren heads and relocation of some of the sirens. At that time, the current system of 20 strategically located sirens was evaluated as adequate for audible outdoor overlapping coverage of the majority of the community. The sirens are designed to be heard outside and may not necessarily be heard when inside a structure.
At this time, there are no immediate plans to add more sirens, but it is a process of ongoing evaluation based on audible coverage and city growth patterns.
Q. How loud are the sirens? Can the sirens be turned up / made louder?
A. The siren volume is set to the maximum level available, which is 130db(c) output at 100 feet. The effective range is 70 db at 6200 feet.
Q. Has tree growth decreased the impact of sirens?
A. We do not believe that tree growth has had any significant impact on siren effectiveness.